bluuebunny/crossref_metadata_2025 huggingface dataset:
The arrangement of multipolar molecules on the surface of graphite
Authors: Spurling TH , Lane JE
Published: September 2010

Grand ensemble and
canonical ensemble Monte Carlo methods have been used to calculate the full
distribution functions for a multipolar molecule adsorbed onto a graphite
surface.
Generalized van der Waals theory. I. Basic formulation and application to uniform fluids
Authors: Nordholm S , Haymet ADJ
Published: September 2010

A generalized van der Waals theory is derived on
the basis of simple physical and mathematical arguments. The derivation results
in a free- energy functional wherein the independent variable is a
coarse-grained particle density. It is assumed that a well defined particle
density dominates the free energy and this density is to be obtained by
minimizing the free energy functional. The variational theory so obtained can
be applied to non-uniform fluids. In the present work the possibility of stable
non-uniform structure is neglected and the theory is applied to uniform fluids.
It then produces an equation of state identical in form to that proposed
originally by van der Waals
but the excluded volume is only about half as large in the three-dimensional
case. Applications to several two- and three-dimensional systems indicate that
the new equation of state is a distinct improvement over the traditional van der Waals theory when the full
range of fluid densities is considered. The quantitative accuracy in the case
of simple uniform fluids is sufficient to warrant further development and
exploitation of the theory.
A surface-active merocyanine dye as a probe of micellar environments
Authors: Donchi KF , Robert GP , Ternai B , Derrick PJ
Published: September 2010

The merocyanine dye
4-[2-(1-hexadecyl-1,4-dihydropyridin-4-ylidene)ethylidene]cyclohexa-2,5-dien-1-one
has been synthesized, and its properties as a probe of micellar
microenvironments have been investigated. The dye is solubilized by micelles,
and its merocyanine terminus is accommodated in a polar environment. The
u.v./visible absorption spectrum of the dye provides a measure of solvent polarity
in this microenvironment, and provides information concerning the pH.
Determination of the critical micelle concentration is conveniently achieved by
noting the abrupt change in the absorption of the dye.
Bimolecular reactions of nucleophiles in the gas phase. The reaction of the methoxide anion with ketones. An ion cyclotron resonance study
Authors: Klass G , Bowie JH
Published: September 2010

The methoxide anion
(produced from methyl nitrite) reacts with neutral ketones (M) to form non-decomposing(M-H+)-
ions. The (M-H+)- ions are ambident species and they
undergo a number of ion-molecule reactions, including (i) characteristic
reactions through the carbanion centre with methyl nitrite, and (ii) for acetone,
the formation of an [M +(M- H+)]- ion. In several cases
peaks due to collision-stabilized (M+MeO-) ions are observed (e.g.
MeO-/acetone), but they are not detected for the majority of cases studied.
Unfused heterobicycles as amplifiers of phleomycin. I. Some pyridinyl- and pyrazolyl-pyrimidines, bithiazoles and thiazolylpyridines
Authors: Brown DJ , Cowden WB , Grigg GW , Kavulak D
Published: September 2010

Syntheses are reported for
some simple derivatives of 2-(pyridin-2'- yl)pyrimidine;
4-(pyrazol-1'- yl)pyrimidine; 4-(pyrazol-4'- yl)pyrimidine; 4,5'-bithiazole; 2-, 3-, and
4-(thiazol-4'-yl)pyridine and 2-, 3-, and 4-(thiazol-2'-yl)pyridine. Biological
activities, as amplifiers of phleomycin against in vitro cultures of
Escherichia coli, are tabulated and discussed.
Formation of hydroxo-bridged copper(II) complexes by aeration of metallic copper
Authors: Beveridge SJ , Walker WR
Published: September 2010

When air is bubbled into an
aqueous suspension of metallic copper in the presence of a chelate such as
1,10-phenanthroline (phen) and 2,2'- bipyridine (bpy), the copper dissolves and
binuclear hydroxo- bridged complexes such as

������������������������� �����������OH������������������������� [(chel)Cu����� Cu(chel)]X2,xH2O ������������������������������������ OH

are formed (chel = chelate;
2X = CO32-, X = ClO4- and Cl-).The dichlorides of such binuclear complexes
have been prepared previously by aeration of freshly precipitated suspensions
of CuCl. In the case of glycine, however, only the bis(glycinato)copper(II)
complex is formed from metallic copper. ��� These observations afford some evidence for
the production of free radicals such as ·OH and may be relevant to
the mechanism of action of both the copper i.u.d, and the 'copper bracelet'.
Calorimetric study of deuterium isotope effects in water-acetic acid systems
Authors: Khurma JR , Fenby DV
Published: September 2010

The molar excess enthalpies
of water+acetic acid systems are analysed to give the
enthalpy of the reaction
������������� 2HA(1)+D2O(1) →
2DA(1)+H2O(1) (A=CH3COO or CD3COO)
the value obtained at 298 K
is -0.15�0.04 kJ mol-1. Molar excess enthalpies at 298.15 K are
reported for the systems H2O+CH3COOH, H2O+CD3COOD,
D2O+CH3COOH and D2O+CD3COOD.
The effect of fluoride, zinc, strontium, magnesium and iron on the crystal-structural disorder in synthetic carbonated apatites
Authors: Featherstone JDB , Nelson DGA
Published: September 2010

The purpose of this study
was to investigate the effect of trace metals and fluoride on structural
disorder in carbonated apatites and to consider the relevance of the results to
dental apatite (enamel). Synthetic carbonated apatites were precipitated in the
presence of low levels of zinc, magnesium, strontium, iron and fluoride.
Crystal imperfection, as indicated by X-ray peak half-widths, was altered
markedly by the substituents. Fluoride alone was effective and zinc- fluoride
was the most effective combination in compensating for disorder caused by
carbonate inclusion. These results show that disorder induced by carbonate
inclusion can be modified greatly by appropriate elements. Trace-element
inclusions may therefore markedly affect dental enamel reactivity. Carbonate
content alone cannot be used as an indicator of the reactivity of apatite or of
the potential susceptibility of dental enamel to caries.
Central nervous system active compounds. III. The synthesis of 4- and 6-substituted caprolactam derivatives by the Schmidt and Beckmann rearrangements
Authors: Hutchison GI , Prager RH , Ward AD
Published: September 2010

The synthesis is described
of hexahydroazepin-2-ones (caprolactams) bearing 1-4 alkyl or aryl groups at C4
and C6 by the Beckmann or Schmidt reactions on the corresponding
cyclohex-2-enone. Further evidence for the mechanism of the Beckmann
rearrangement of these unsaturated oximes is advanced. The central nervous
system activity of the alkylated caprolactams is reported.
Triphenylantimony(V) complexes with Schiff bases
Authors: Jain VK , Bohra R , Mehrotra RC
Published: September 2010

Twelve new octahedral
complexes of the type Ph3Sb(Cl)(OC6H4CR=NR')
(where R = H and R' = Me, Et, Pr, Bu, Ph and p-tolyl;
R = Me and R' = Me, Bu and Bu') and Ph3Sb(OMe)-(OC6H4CR=NR')(R
= H and R' = Me; R = R' = Me) have been synthesized and characterized after
purification by recrystallization. The results of the i.r.
and 1H n.m.r. spectra of these complexes suggest coordination of
azomethine nitrogen to the antimony atom.
An improved synthesis of 6-Methoxyanthranilic acid
Authors: Warrener RN , Russell RA , Marcuccio SM
Published: September 2010

6-Methoxyanthranilic acid
(1) is prepared in three steps from 2,6- dinitrobenzoic acid (6) in an overall
yield of 46%.
Electrochemical aspects of leaching copper from chalcopyrite in ferric and cupric salt solutions
Authors: Parker AJ , Paul RL , Power GP
Published: September 2010

Electrochemical aspects of
semiconductors are used to interpret well established observations on the
kinetics of leaching of chalcopyrite. The oxidation of this n-type
semiconductor is dominated by a surface film which is thermally unstable and
breaks down in CS2, acetone or acidified water, or under dry
nitrogen, over comparable time periods. The film is thought to be a
semiconductor metal-deficient polysulfide which slows transport of Cu+
and Fe2+ products, slows electron transfer to oxidants such as Fe3+
and Cu2+, and dramatically slows supply of holes and thus electron
transfer from reduced species such as Fe2+ on corroding
chalcopyrite. Thus the Fe3+/Fe2+ couple (especially as
sulfate) is much less reversible on corroding chalcopyrite than on pyrite or platinum.
The couples Cu2+/Cu+,I3-/I-
and Fe(CN)63-/Fe(CN)64- are more
reversible than Fe3+ /Fe2+ but all couples are much less
reversible on chalcopyrite than on pyrite. A layer of sulfur forms on corroding
chalcopyrite, but this is not the species which slows transport of ions and
transfer of electrons. A mixture of Fe3+/Cu2+ chlorides
is one of the more effective oxidants for CuFeS2 because of
relatively fast electron transfer from corroding chalcopyrite to Cu2+
and oxidation of Cu+ by Fe3+. Catalysis by iodine and by
inclusion of Ag2S or FeS2 in natural chalcopyrite is
explained by the electrochemical model.
Hydrogen-1, carbon-13, phosphorus-31 and selenium-77 n.m.r. studies on organophosphorus selenides
Authors: Carr SW , Colton R
Published: September 2010

Hydrogen-1,carbon-13,phosphorus-31
and selenium-77 n.m.r. studies have been carried out on some organophosphine
selenides. The n.m.r. studies show that the ditertiary phosphine Ph2PCH2PPh2
reacts with the SeCN- ion to give predominantly the monoselenated derivative Ph2P(Se)CH2PPh2,
but with the diphosphine Ph2P(CH2)2PPh2
the diselenated derivative is obtained. A qualitative study of the solvent
dependence of selenium-77 chemical shifts is reported.
Conformational analysis of coordination compounds. XI. Molecular structure of tetraammine{(±)-pentane-2,4-diamine)cobalt(III) dithionate
Authors: Hambley TW , Hawkins CJ , Palmer JA , Snow MR
Published: September 2010

The crystal structure of tetraammine{(�)-pentane-2,4-diamine}cobalt(III) dithionate dihydrate [Co{(�)-ptn}(NH3)4]
(S2O6)1.5,2H2O has been determined
by X-ray structure analysis. The crystals are triclinic with the space group Pī, with a
11.43, b 11.65, c 7.78 �, α 100.48�, β 105.95�, and γ 75.95�. The
structure has been refined by least-squares methods with anisotropic
temperature factors to an R value of
0.043 for 2654 reflections. The six-membered diamine
chelate ring has a skew-boat conformation in which the two methyl groups are in
equatorial orientations. A strain- energy-minimization calculation for the
complex reveals an energy difference of 8.3 kJ mol-l between the
preferred skew-boat conformation and the chair conformation. The calculated
minimum-energy geometry for the skew-boat conformation is in good agreement
with the observed structure for the chelate ring in the dithionate salt. The lH
N.M.R. spectra of this complex and other complexes of the chiral isomer of
pentane-2,4-diamine are discussed in terms of the observed structures and the
conformational analysis.
Bisphenol flukicides. IV. Conformational studies of two halogenated bisbenzyl phenols : 2,6-Bis(3'-bromo-5'-chloro-2'-hydroxybenzy1)-4-fluorophenol and 2,6-bis(3'-bromo-5'-chloro-4'-hydroxybenzyl)-4-fluorophenol
Authors: Sindt-Josem AC , Mackay MF
Published: September 2010

Monoclinic crystals of an
ethyl acetate adduct of 2,6-bis(3�-bromo-5�-chloro-2�-hydroxybenzyl)-
4-fluorophenol (l),⅓EtOAc, C20H13Br2Cl2FO3⅓(C4H8O2),
belong to the space group P21/c with a 11.943(2), b
25.395(15), c 7.287(1) �, β
96.56(1)�, Z 4. Crystals of the isomeric compound, 2,6-bis(3�-bromo-5�-chloro-4�-hydroxybenzy)-4-fluorophenol
(2), belong to the monoclinic space group C2/c with a 8.853(4), b 14.246(3), c 15.972(4) �, β 98.49(3)�, Z 4.
The structures were refined with diffractometer data measured with Mo Kα radiation to R
0.059 (2243 terms) for (l),⅓EtOAc and R 0.060
(1119 terms) for (2). The conformation of each bisbenzylphenol
molecule can be described in terms of two chemically equivalent diphenylmethane
moieties with the 4-fluoro- phenol ring common to both. In the molecules of (1),
the moieties adopt skew and butterfly conformations. For the former, the dihedral angles between the
perpendiculars to the plane of the C-CH2-C bridge and the bromochlorophenol and fluorophenol
rings are 19.0� and 85.0� respectively, while, for the butterfly conformation,
the analogous angles are 84.8� and 88.8�. Molecules of (2) have exact C2
symmetry and the conformation of the bridged diphenyl moiety is skew, with
dihedral angles between the perpendiculars to the C-CH2-C plane and
the bromochlorophenol and fluorophenol rings of 27.0� and 78.1� respectively.
Alkaloids of Cryptocarya longifolia: X-Ray Crystal Structure of Thalifoline and Longifolonine
Authors: Bick IC , Sevenet T , Sinchai W , Skelton B , White A
Published: September 2010

The known alkaloids reticuline (1), coclaurine (3),
N-methylcoclaurine (2), laurotetanine
(7), N-methyl-laurotetanine (8), laurolitsine
(10), isoboldine (9), norisocorydine
(6), norargemonine (ll), bisnorargemonine
(12), thalifoline (16) and scoulerine
(13) were isolated from the New Caledonian plant Cryptocarya longifolia together with two
new bases, longifolidine (4) and longifolonine
(14). Spectroscopic methods were used for identification and structural
investigation, and X-ray crystallographic analysis to determine the structures
of thalifoline and longifolonine.
A phosphorus-31 nuclear magnetic resonance study of triphenylphosphine oxide exchange on magnesium(II) and zinc(II)
Authors: Lincoln SF , Pisaniello DL , Spotswood TM , Tkaczuk MN
Published: September 2010

31P n.m.r, studies show that the rate of triphenylphosphine oxide exchange on [Zn(O=PPh3)4]2+
in CD2Cl2 solution is independent of [O=PPh3]free. A typical data set is: kex(200 K) = 611 ± 37 s-1,
ΔH‡ = 32.0 ± 0.7 kJ mol-1 and ΔS‡ = -28.3 ± 3.4 J K-1 mol-1 for a solution in which
[Zn(O=PPh3)42+] and [O=PPh3]free are 0.163 and 0.639 mol dm-3 respectively, where
kex = exchange rate/(4[Zn(O=PPh3)42+])= (kBT/h)exp(-ΔH‡/RT)exp(ΔS‡/R)
Similarly the rate of ligand exchange on [Mg(O=PPh3)5]2+ is shown to be independent of
[O=PPh3]free and a typical data set is kex'(220 K) = 38 ± 4 s-1, ΔH‡ = 73.7 ± 1.8 kJ mol-1 and
ΔS‡ = 123 ± 8 J K-1 mol-1 for a solution in which [Mg(O=PPh3)52+] and [O=PPh3]free are 0.0813
and 0.276 mol dm-3 respectively. The ligand exchange process on both species is considered to
proceed through a D mechanism. The apparent equilibrium constant K = [Mg(O=PPh3)52+]/
([Mg(O=PPh3)42+][O=PPh3] ≥ 150 dm3 mol-1 but in contrast [Zn(O=PPh3)2+ appears to be the
only stable zinc(II) species in solution. It is concluded that these data probably reflect the hard
acid character of magnesium(II) and the intermediate acid characteristics of zinc(II).
Phosphorus-31 and mercury-199 N.M.R. studies of mercury(II) complexes with some tertiary phosphines
Authors: Colton R , Dakternieks D
Published: September 2010

Phosphorus-31 and
mercury-199 n.m.r. techniques have been used to investigate the formation of
mercury(II) complexes HgA2(phos)1-4
[where A = ClO4-, NO3-, CF3COO-,
CH3COO-, SCN-, CN-, Cl-,
Br-, I- and phos = P(4-ClC6H4)3,
P(4-CH3OC6H4)3, P(2-CH3OC6H4)3,
P(4-CH3C6H4)3, P(2-CH3C6H4)3,
P(3-CH3CH6H4)3, PBu3,
P(C6H11)3 and PPh3] in
dichloromethane solution. The number of phosphines
coordinated to the mercury depends upon the steric requirements of the
phosphine and the nature of the anion A. Phosphorus-31 and mercury-199 chemical
shifts and coupling constant data imply coordination of all the anions, except perchlorate, to mercury. Mercury chemical shifts are
discussed in terms of electron density at the metal and coordination number of
the metal.
Studies on chloroplast membranes. IV. 13C chemical shifts and longitudinal relaxation times of 3-sn-phosphatidylglycerol
Authors: Coddington JM , Johns SR , Leslie DR , Willing RI , Bishop DG
Published: September 2010

13C chemical shifts, longitudinal relaxation times and
some nuclear Overhauser enhancement factors of
individual carbon atoms in the chloroplast lipid, 3-sn-phosphatidylglycerol (pg), have been measured in (D4)methanol
and (D)chloroform. Correlation times for individual carbon atoms calculated
from these results have been interpreted in terms of different secondary
structures: a monomeric structure in (D4)methanol and an inverted
micelle in (D)chloroform. Differences in structures between the four major lipid
components of the chloroplast membrane are briefly discussed.
Central nervous system active compounds. VII. Phthalide synthesis by lithiation of alkoxyaromatics
Authors: Hung TV , Mooney BA , Prager RH , Tippett JM
Published: September 2010

The lithiation
of methoxy- and methylenedioxy-bemyl alcohols is
described; subsequent reactions with ethyl chloroformate
and carbon dioxide to form phthalides have been
investigated, and are compared with metallation-carboxylation
of alternative substrates. The preparation of phthalideisoquinoline
analogues by this method proceeds only in low yields due to the acidity of the
benzylic position in the benzylisoquinoline
precursor.
Isobenzofulvenes. VIII. The structure of the dimers derived from 8,8-dimethylisobenzofulvene. A PMO treatment of the perispecificity in this dimerization and related cycloadditions involving isobenzofulvenes
Authors: Warrener RN , Paddon-Row MN , Russell RA , Watson PL
Published: September 2010

8,8-Dimethylisobenzofulvene, generated from the reaction of ll-isopropylidenetricyclo[6,2,1,02.7]-
undeca-2,4,6,9-tetraene (23) and 3,6-di(pyridin-2-yl)-s-tetrazine, undergoes spontaneous dimerization
to form a mixture of two isomers. This is shown to be a mixture of endo (33) and exo isomers
(37) resulting from [π10s+π8s] cyclodimerization, with the former isomer predominating. 1H and
13C n.m.r. spectroscopy, in conjunction with lanthanide shift reagents and spin decoupling, was used,
together with chemical degradation, to determine the structure and stereochemistry of these products.
Chemical interconversion has placed these structures on a firm basis since the structure of the minor
isomer has been determined by X-ray structure analysis. The constancy of this dimer ratio in
solvents of widely differing polarity, and in the absence of solvent, supports an isopolar transition
state which is typical of many concerted electrocyclic processes.
A complete PMO treatment of all possible modes of isobenzofulvene dimerization is presented
and the results of these calculations are discussed in terms of the observed peri- and stereospecificities.
In a similar way, the PMO model is successfully employed to explain the relative
efficiencies of various polyenophiles in trapping the isobenzofulvene nucleus.
The microwave spectrum and structure of phosphaethene, CH2=PH
Authors: Brown RD , Godfrey PD , McNaughton D
Published: September 2010

The microwave spectra of
phosphaethene (methylenephosphine) and five of its isotopic species have been
observed and assigned in the region 5-125 GHz. Rotational constants and moments
of inertia have been determined for 12CH2PH, 13CH2PH,
12CD2PD, 12CD2PH, (Z)-12CHDPH and (E)-12CHDPH. The moments of
inertia have been used to determine the following structural parameters: rP-H= 1.425�; rC-P=
1.671�; rC-H,= 1.082�; <HCP(Z) = 124.5�; <HCP(E)
= 119.1�; <CPH = 95.5�. The dipole moment components have been determined as
�a = 0.7233(7) D and �b =
0.4657(ll) D.
The use of 13C N.M.R. spectroscopy for the characterization of carbonates, thiocarbonates, dithiocarbonates and trithiocarbonates
Authors: Copeland C , Conway RJ , Patroni JJ , Stick RV
Published: September 2010

The 13C nuclear
magnetic resonance chemical shifts are reported for a variety of carbonates
(δ 154),thiocarbonates (δ 193 for OCSO, δ 170 for SCOO),
dithiocarbonates (δ 215 for SCSO, δ 188 forSCOS) and trithiocarbonates
(δ 224).
Colouring matters of Australian plants. XXIV. Haemofluorone B : New synthetic models and a revised structure
Authors: Chaffee AL , Cooke RG , Dagley IJ , Perlmutter P , Thomas RL
Published: September 2010

The occurrence of
haemofluorone B in Anigozanthos rufus
and Conostylis setosa has been
confirmed. The revised structure 5,8,9-trihydroxy-3H-naphtho[2,1,8-mna]xanthen-3-one
is now proposed for this pigment. Dihydroxyanigorufone has also been found in Conostylis setosa and the structure 9-(3,4-dihydroxyphenyl)-2-hydroxy-lH-phenalen-l-one has been confirmed by
synthesis of the trimethyl ether. Some model arylphenalenones and
naphthoxanthenones have been prepared fromnaphthylphenylpropanones
and some unusual products have been obtained by photolysis of arylphenalenonesand by the reactions of
Grignard reagents with phenalenones.
Studies on reductive alkylation. A highly efficient synthesis of the phytoalexin orchinol
Authors: Gunter MJ , Mander LN
Published: September 2010

Reductive alkylation of 2,5-dimethoxybenzoic
acid (1) with 2-(3',5'-dimethoxyphenyl)ethyl iodide (2) followed by
cyclodehydration and oxidative decarboxylation afforded orchinol (5) in high
overallyield. A simple synthesis
of iodide (2) based on the reductive alkylation of 3,5-dimethoxybenzoic acid
(6) was also developed.
Ultraviolet absorption spectra of the 2-Phenylethyl radical formed during pulse radiolysis
Authors: McAskill NA , Sangster DF
Published: September 2010

2-Phenylethyl radicals
(Ph-CH2-�CH2) were prepared by the decarboxylation
reaction of 3-phenylpropanoic acid with sulfate radical ions (SO4-�)
formed during the pulse radiolysis of aqueous solutions containing
peroxydisulfate (S2O82-) ions. The ultraviolet
absorption spectrum of the transient radicals consisted of a band centred at
309nm with an extinction coefficient of 5000 1, mol-1 cm-1.
Attempts were made to form phenylethyl radicals by the electron-attachment
dissociation reaction of (2-haloethy1)benzenes. Contrary to literature reports,
it was found that the latter reaction does not occur in either cyclohexane,
benzene or aqueous solutions of (2-chloroethyl)- and (2-bromoethyl)-benzenes.
A tetranuclear carbonyl fluoro rhenium(I) cluster, [Re(CO)3F]4,4H2O
Authors: Horn E , Snow MR
Published: September 2010

The title compound has been
prepared from Re(CO)5Br by a bromide-abstraction reaction with
silver fluoride. It completes the series of known halide clusters of the type
[Re(CO)3X]4 (where X = halide). The crystals are
tetragonal, space group 14, with a 11.716(5), c 8.988(3) �, and Z 2. The structure was refined by full-matrix
least-squares to an R value of 0.027
for 1380 observed reflections. The molecules are cubane-type
clusters of Re(CO)3 groups at one set of corners interpenetrated
with fluorine atoms at the other set. The clusters exhibit the molecular
symmetry 43m. Each of the fluorine atoms is involved in μ3 type bridging with the rhenium atoms at an
average bonding distance of 2.200(5) �. The clusters are held together by
hydrogen bonding of fluoride to water molecules.
Crystal and molecular structure of Bis(4-amino-3,5,6-trichloropicolinato)-manganese(II) dihydrate
Authors: Smith G , O'Reilly EJ , Kennard CHL
Published: September 2010

The manganese(II) complex
[Mn(picl)2,2H2O]n
of the herbicide picloram has been prepared and the crystal and molecular structure
determined from three-dimensional X-ray data collected by counter methods. The
crystals of the complex are monoclinic, space group 12/a with two complex units in a cell of dimensions a 23·052(5), b 13·840(2), c 6·441(1)
�, β 98·20(1)�. The structure was solved by direct methods and refined
by full matrix least squares to unweighted and weighted Rfactors of 0·035 and 0·038
respectively for 887 'observed' reflections. The polymer is best described as
having a centrosymmetric two-molecule unit [Mn-O, 2·162(3), 2·246(3) �]
with two oxo bridges between manganese centres through two single carboxylate
oxygens of the four substituted picolinate ligands. The two molecules are
related by a twofold axis. The units form infinite one-dimensional polymer
chains in the c direction through oxo
bridges involving one oxygen from the other two picolinate ligands [Mn-Mn 3·636(1)�].
The bis(bidentate)picolinate bites are completed by the pyridlne nitrogens [Mn-N,
2·313(4) �] giving a very distorted octahedral MnO4N2
coordination sphere about each manganese [N-Mn-N', 97.0(3)�; O-Mn-O range, 68·9-168.2(3)�;
O-Mn-Nrange, 69·9-138·5(3)�].
The lattice waters are involved in hydrogen-bonding interactions which link the
polymer in the a crystallographic
direction with the uncoordinated carboxylate oxygen ( O···O,2·824,
2·936 �) and the 4-amino groups from the adjacent picolinate ligand (N·
··0, 2·852, 3·030�).
Solar reduction of water. I. Competition between light-induced hydrogen formation and hydrogenation of methylviologen in the system water-Tris(2,2'-bipyridine)ruthenium dication-ethylenediaminetetraacetic acid-platinum
Authors: Johansen O , Launikonis A , Loder JW , Mau AWH , Sasse WHF , Swift JD , Wells D
Published: September 2010

The light-induced formation
of hydrogen in the system H2O-Ru(bpy)32+-mv2+-edta-Pt
(mv, inethylviologen) is accompanied by the hydrogenation of mv2+ to
give the 1-methyl-4-(1'-methylpiperidin-4'-yl)pyridinium cation (1). The
production of hydrogen is decreased by factors that favour the formation of
this cation. The extent of hydrogenation depends on the pH of the mixture, the
amount and type of catalyst present, and the partial pressure of hydrogen
during irradiation.
A 13C N.M.R. study of some agar-related polysaccharides from New Zealand seaweeds
Authors: Brasch DJ , Chuah C , Melton LD
Published: September 2010

The use of 13C
nuclear magnetic resonance spectroscopy has yielded well resolved spectra of
agaroses from marine algae of the Pterocladia
species and Gracilaria secundata, and
from the porphyran and alkali-modified porphyran of Porphyra columbina. A complete assignment of all signals in the
spectra of these four undegraded polysaccharides has been made on the basis of 13C
n.m.r. spectra which have been reported for various galactose derivatives and
agaro-oligosaccharides. General shifts rules for carbohydrates have been used.
Conformational aspects of the work are briefly discussed.
A radial flow streaming potential apparatus for electrokinetic studies of sheet or plate materials
Authors: Lyons JS , Furlong DN , Homola A , Healy TW
Published: September 2010

A radial flow streaming
potential (r.f.s.p.) apparatus, and the procedure
adopted for streaming potential determination, are described. It is shown by
consideration of apparatus design and by experiment that the conditions
necessary for valid application of the Helmholtz-Smoluchowski
equation for zeta-potential calculation are satisfied by the r.f.s.p. technique. Zeta-potential data for fused silica
discs determined by the r.f.s.p, technique are found
to be in good agreement with previous studies on other forms of silica.
Application of the Gouy-Chapman- Stern-Grahame double-layer theory to enable
calculation of surface potential (ψo) shows it to be independent of salt
concentration and to change by 30 mV per pH unit, both results providing
verification of the soundness of the r.f.s.p.
technique.
Preparation and trapping of 1-Acetoxyisobenzofuran. The structure of a novel phthalide formed in the attempted generation of 1-Acetoxyisobenzofuran in the presence of quinones
Authors: Russell RA , Marsden DE , Sterns M , Warrener RN
Published: September 2010

A new potential synthesis
of anthraquinones based upon 1-acetoxyisobenzofuran (4) is reported. The key
reaction used to generate isobenzofurans, namely the s-tetrazine reaction,
proceeds smoothly in the presence of N-methylmaleimide to yield the expected adduct
(16). In contrast, the reaction takes a different path in the presence of
quinones to yield a novel phthalide (15). These reactions are considered to
involve a non-concerted fragmentation of the intermediate dihydro-pyridazine
(3) to yield the stabilized zwitterionic species (13). The zwitterion leads on
to the phthalide (15) in a two step sequence involving the quinone as oxidant,
while normal fragmentation is the sole reaction in the absence of oxidant. ��� The structure of 3-[3',6'-di(pyridin-2''-yl)pyridazin-4'-
yl]isobenzofuran-1(3H)-one (15) has been determined
by single crystal X-ray diffraction and refined by full-matrix least squares to
a residual of 0.107 for 1389 'observed' reflections. Crystals are monoclinic,
P21/c, a 8.271(2), b 19.183(4), c 11.814(2)Ǻ, β 110.0(1)β.
Reaction of 3,4-Diaminopyridazine with α,β-Dicarbonyl compounds, carbon disulfide and urea, and methylation of some of the products
Authors: Barlin GB
Published: September 2010

3,4-Diaminopyridazine has
been shown to condense with benzil, diacetyl and phenylglyoxal to give
6,7-diphenyl-, 6,7-dimethyl- and 6(7)-phenyl- pyrazino[2,3-c]pyridazine,
respectively. ��� Syntheses of 2-, 5- and
7-methyl-6-methylthioimidazo[4,5- c]pyridazine have been described. Methylation
of 6-mercaptoimidazo[4,5- c]pyridazine with diazomethane gave 1- and
7-methyl-6- methylthioimidazo[4,5-c]pyridazine but methyl iodide gave 1- and 2-
methyl-6-methylthioimidazo-[4,5-c]pyridazine. Diazomethane methylation of 6-hydroxyimidazo[4,5-c]pyridazine
gave three dimethyl derivatives of which one was identified as 6-methoxy-1-methylimidazo[4,5-c]pyridazine.
Regioselective bromination of 1,4-naphthoquinones
Authors: Cameron DW , Feutrill GI , Griffiths PG
Published: September 2010

1,4-Naphthoquinones
unsymmetrically substituted in the benzenoid ring undergo bromination at the 2-
and/or 3-positions. The isomeric composition of the products is strongly
influenced by the conditions of bromination, addition of hydrogen bromide
usefully complementing the conventional procedure involving addition of
bromine. In favourable cases, involving methoxynaphthoquinones, these two
procedures afford controlled access to individual 2- and 3-bromo derivatives.
The thermodynamics of a new type of surface transition
Authors: Lane JE , Spurling TH
Published: September 2010

In a recent paper we have
reported the existence of a first-order phase transition which occurs at a
characteristic distance of separation between two adsorbing walls. In this
paper we discuss some of the thermodynamic properties of this new transition.
The viscosity of liquid mixtures
Authors: Alexander DM , Moy DC
Published: September 2010

A semiempirical equation is
proposed to describe the effect on the viscosity of a solvent due to the addition
of a solute. This equation is applied to many types of mixtures but not those
for which components are electrolytes or water. The B coefficient at infinite
dilution is B°2 = V·1
+ V·2 /2[ln��
η·2�/In η·1 -
H°/2-H·2
/ 2.45RT ]
where H°2-H·2
is the heat of solution of the liquid solute, V·1 and V·2
the molar volumes and η·2 and η·1
the viscosities of the pure components.
Micellar catalysed hydrolysis of amides. II. N-Ethyl-4-nitrotrifluoroacetanilide in functional and non-functional micelles
Authors: O'Conner CJ , Porter AJ
Published: September 2010

The reactivity of
N-ethyl-4-nitrotrifluoroacetanilide has been examined in the presence of a non-functional
detergent (n- hexadecyltrimethylammonium bromide) and
three functional detergents, n-hexadecyl(2-hydroxyethyl)dimethylammoniumchloride, n- hexadecyl(imidazol-4-ylmethyl)dimethyl-ammonium
chloride and n-hexadecyl(2-hydroxyethyl)(imidazol-4-ylmethyl)methylammonium chloride, at 293.5 K and in borate buffer
(1.3 × 10-3 mol dm-3, pH 9.0). The variation of the rate
constants for the overall reaction with surfactant concentration has been
analysed in terms of the reactant concentrations and rate constants in each
pseudophase, the micelle binding constant and the critical micelle
concentration, CMC. Surface tension measurements have been made on solutions of
these surfactants. The values of CMC have been measured with, and without, the
addition of a kinetic concentration of amide and the results compared with
those from the kinetic analysis.
Constituents of Endiandra species. I. Endiandric acid, a novel carboxylic acid from Endiandra introrsa (Lauraceae), and a derived lactone
Authors: Bandaranayake WM , Banfield JE , Black DSC , Fallon GD , Gatehouse BM
Published: September 2010

X-ray crystallographic
analysis shows that endiandric acid and a derived lactone have the respective
structures 2-(6'- phenyltetracyclo[5,4,2,03,13,010,12]trideca-4',8'-dien-11'-yl)acetic
acid and 12-phenyl-3-oxapentacyclo[7,5,2,02,6,07,15,013,16]hexadecan-4-one.
Halo lactones in the Bicyclo[2,2,2]octane series
Authors: Alberts V , Brecknell DJ , Carman RM , Smith SS
Published: September 2010

Stable lactones formed from
bicyclo[2,2,2]oct-5-ene-2-carboxylic acids and their derivatives by halolactonization
are shown to be γ-lactones.
Methylation of heterocyclic compounds containing NH, SH and/or OH groups by means of N,N-dimethylformamide dimethyl acetal
Authors: Stanovnik B , Tisler M , Hribar A , Barlin GB , Brown DJ
Published: September 2010

Methylations of
heterocyclic systems, such as benzimidazole, naphth[2,3-c]imidazole,
imidazo[4,5-c]-pyridine, purine, pyridine, pyrimidine, pyridazine and
s-triazolo[4,3-b]pyridazine, which bore SH, NH and/or OH groups, were carried
out with dimethylformamide dimethyl acetal to give the corresponding S-, N-
and/or O-methyl derivatives in high yields. Selective methylation of some compounds
containing both SH and NH groups took place to give first the S-methyl and
subsequently the S,N-dimethyl derivatives. No side reactions, such as
C-methylation, were observed.
The synthesis of the isomeric N-methyl derivatives of murexine
Authors: Duke CC , Eichholzer JV , Macleod JK
Published: September 2010

The two isomeric N-methyl
derivatives of murexine have been synthesised by independent routes and shown
to be different from an 'N- methylmurexine'
reportedly isolated from the mollusc Nucella emarginata. 1H n.m.r.
studies have shown a marked difference in the extent of binding to paramagnetic
ions of the two N-methyl derivatives of murexine in water while pharmacological
results show substantially different pharmacological activities of the two
isomers. Both results can be rationalized in terms of the observed activities
being associated with the presence of one or the other of the tautomeric forms
of the imidazole ring.
Differential thermal analyses of solid-solid transitions in AgNO3 under hydrostatic pressures to 0.7 Gpa
Authors: Cohen LH , Klement Jr W
Published: September 2010

Differential thermal
analyses have located the transitions between low-temperature I and
high-temperature II phases in AgNO3 powder and single crystals under
hydrostatic pressures </~0.7 GPa, with
heating/cooling rates in the range 0.1-1.5 K s-1. Isobaric
transition temperatures plot linearly against heating/cooling rates and,
extrapolated to zero rate, show hystereses between I → II and II →
I transition temperatures which are comparable with the 'regions of
indifference' of Bridgman's isothermal experiments. The present results suggest
an initial slope of -0.090 μK Pa-1
and zero initial curvature for the I-II phase boundary. Greater hystereses are
observed for the I-II transitions near intersection with the II-II' λ
transition at </~0.7 GPa. An improved,
quantitative description is achieved for the Kennedy-Schultz data on the linear
growth rates of II,II? → I at 0.1 MPa. For II' (with
ordered NO3- ions) → I the growth rates show
temperature dependence markedly different than growth rates for II(with
disordered NO3-) → 1 and I → II.
The reduction of gold(III) dithiocarbamates at the mercury electrode
Authors: Ahmed M , Magee RJ
Published: September 2010

The reduction at the
mercury electrode of a series of gold(III) dithiocarbamates [Au(S2CNR2)3]
in propylene carbonate solution has been investigated by d.c.
polarography, cyclic voltammetry and chronoamperometry. ��� Under polarographic conditions, the complexes
undergo reduction in a single, diffusion-controlled step. Exhaustive reduction
of the complexes at the mercury pool electrode gave non-integral values (3 >
n > 2), suggesting the presence of a coupled chemical reaction involving
dissociation of the product of the first reduction step. ��� At short electrolysis times (t < 2 s),
the slopes of the chronoamperometric i against t-½ plots were typical of
two-electron reductions. At longer electrolysis times (t > 4 s), the slopes
approached a three-electron reduction. ��� Cyclic voltammetry confirmed that the
products resulting from the first reduction are susceptible to dissociation,
releasing free dialkyldithiocarbamate anion.
Studies on gibberellin synthesis. Assembly of an ethanophenanthrenoid lactone and conversion into a gibbane derivative
Authors: Mander LN , Pyne SG
Published: September 2010

Diazoketone (13), prepared
by standard methods from 5-formyl-8-methoxy-1,2,3,4-tetrahydronaphthalene-2-carboxylic
acid (7), was cyclized in trifluoroacetic acid to dienone (1) which under-went
intramolecular 1,4-conjugate addition to afford the ethanophenanthrene
derivative (15). Refunctionalization furnished dibenzoyloxy diacid (19) which
cyclized in sulfuric acid specifically to the
8-carboxy-10,12-dibenzoyloxyperhydro-1H-2,10a-ethanophenanthrene-8,4b-carbolactone (2). Further
refunctionalization to ketone (22), then formation of diazoketone (23) followed
by photolysis in an aqueous medium, finally gave (1RS,4aRS,4bRS,7SR,8SR,9aSR,10SR,10aRS)-8-benzoyloxy-4a-hydroxy-1-methoxymethyloxymethylgibbane-1,10-dicarboxylic
acid 1,4a-lactone (3) which may serve both as a model and intermediate for a
radically new approach to the total synthesis of gibberellins.
Sporidesmins. XIX. The diazotization and coupling in acid of p-Nitro- and 2,4-Dinitro-aniline to veratrole or guaiacol: 1H N.M.R. of the products in deuterochloroform and deuteroacetone
Authors: Ronaldson JW
Published: September 2010

p-Nitrobenzenediazonium
chloride in conc. HCl coupled to guaiacol
(2-methoxyphenol) to give 4-hydroxy-3-methoxy-4'-nitroazobenzene, but did not
couple to veratrole (1,2-dimethoxybenzene).
2,4-Dinitroaniline, diazotized in conc. HCl with no
urea added, yielded 2-chloro-4,5-dimethoxy- 2',4'-dinitroazobenzene with neat veratrole. However, 2,4-dinitroaniline, diazotized in conc.
HCl and then treated with urea, yielded
2-chloro-4-nitrobenzenediazonium chloride which again coupled in acid with guaiacol to give 2-chloro-4'-hydroxy-3'-methoxy-4-nitroazobenzene
but not with veratrole in acetic acid. Veratrole added to 2,4-dinitrobenzenediazonium phosphate or
trichloroacetate in acid media yielded
3',4'-dimethoxy-2,4-dinitroazobenzene. These 2,4-dinitrobenzenediazonium salts
coupled to guaiacol giving
4'-hydroxy-3'-methoxy-2,4-dinitroazobenzene. p-Nitrobenzenediazonium and
2-chloro-4-nitrobenzenediazonium salts in acid gave the Gomberg
reaction with veratrole forming the corresponding
biphenyls. The 1H n.m.r. spectra of all the products obtained in
this investigation and the deshielding effect of deuteroacetone on four of the compounds are discussed. The deuterochloroform spectrum of
4'-hydroxy-3'-methoxy-2,4-dinitroazobenzene at 60 MHz shows an anomalous set of
26 or more lines that are not attributable to a quinone
hydrazone structure.
Structural and spectroscopic studies of transition metal nitrite complexes. VI. Crystal structures and spectra of Hexakis(imidazole)nickel(II) dinitrate, trans-Tetrakis(2-methylimidazole)dinitritonickel(II) and cis-Tetrakis(2-methylimidazole)-(nitrito-O,O')nickel(II) nitrate-methanol (2/1)
Authors: Finney AJ , Hitchman MA , Raston CL , Rowbottom GL , White AH
Published: September 2010

The crystal structures and
spectroscopic properties of the complexes cis-tetrakis(2-methy1imidazole)-(nitrito-O,O')nickel(II) nitrate-methanol (2/1)
and trans-tetrakis(2-methylimidazole)dinitritonickel(II) are reported. The nitrite group in the
former compound chelates, giving a distorted octahedral ligand coordination
geometry. The ligand stereochemistry in the second complex is also a distorted
octahedron, with both anions coordinating as trans nitrito groups though with
significantly different Ni-O bond lengths and the nickel(II) ion being raised
out of the plane of the four imidazole ligand nitrogen atoms towards the closer
nitrite group. The Ni-O bond directions also deviate substantially from the
fourfold symmetry axis in this latter complex. These distortions apparently
occur in order to minimize ligand-ligand repulsions, particularly those
associated with the amine methyl substituents. The electronic spectra of both
complexes show significant band splittings due to the
departure of the ligand field from regular octahedral symmetry and these are
discussed in terms of the relative field strengths of the imidazole and nitrito ligands. The structure of hexakis(imidazole)nickel(II)
nitrate (redetermination) is also reported.
On the reaction of diazomethane with 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone. Formation and crystal structure analysis of 2,5-Diacetoxy-3,4-dichlorocyclohepta-1,3,5-triene-1,6-dicarbonitrile
Authors: Becker H , Skelton BW , White AH
Published: September 2010

The structure of a compound
previously believed to be the diacetate of 2,3-dichloro-5,6-dicyano-4-
hydroxybenzyl alcohol has been analysed by X-ray methods and found to be that
of the isomeric 2,5-diacetoxy-3,4-dichlorocyclohepta-1,3,5-triene-1,6-dicarbonitrile.
Consequently, the product formed in the reaction of diazomethane with
2,3-dichloro-5,6-dicyano-1,4-benzoquinone (ddq), earlier thought to be an
oxirano-substituted cyclohexa-2,5-dienone, is
3,4-dichloro-2,5-dioxobicyclo-[4,1,0]hept-3-ene-1,6-dicarbonitrile.
(1R,4S)-Calamenene. Chemical correlation with the diterpene analogues of Eremophila
Authors: Bunko JD , Ghisalberti EL , Jefferies PR
Published: September 2010

(1R,4S)-(-)-Calamenene has been synthesized from dihydroxyserrulatic
acid of known absolute configuration. (1R,4S)-(-)-8-Methoxycalamenene is shown to
be the enantiomer of a calamenene isolated from the
gorgonian Subergorgia hicksoni
Effects of substituents on ion-association properties. II. 1H N.M.R. studies of substituted pyridinium and tetraalkylammonium Bis(4-methylbenzene-1,2-dithiolato)cobaltate(III) in non-aqueous solvents
Authors: Tsao N , Lim Y
Published: September 2010

A series of nine compounds
containing quaternary ammonium and substituted pyridinium cations and the
bis(4-methylbenzene-1,2-dithiolato)cobaltate(III)
complex anion have been prepared andtheir ion-pair properties
studied by lH n.m.r. spectroscopy. Their concentration
association constants in nitrobenzene at 307 K range from 9 to 20. In the
pyridinium series of ion pairs, it is concludedfrom the measured isotropic
shift ratios that methyl substituents at the meta and para
positions favour a geometry where the anion is tilted towards the ring of the
cation but the ortho
substituents push the anion away from the ring. In the methyltrioctylammonium
ion pair, there is linear correlation between the observed isotropic shift of
the N-methyl or the N-methylene protons and the dielectric constant
of the solvents (E) from 4.56 to 12.3 for the 0.06, 0.09 and 0.12 M solutions.
Its implication is discussed in terms of the formation of the ionic clusters of
sufficiently large size.
Synthesis of substituted tetrafluorocyclobutanes. I. Disubstituted alkenyl, aryl esters
Authors: Johnson WMP , Holan G
Published: September 2010

The main details of the
syntheses of a number of 1,1-disubstituted-2,2,3,3-tetrafluorocyclobutanes are
presented. The substituents at the 1-position are various alkenyl
groups and aryl ester groups
Some reactions of enol-lactones with metal alkoxides
Authors: Massy-Westropp RA , Price MF
Published: September 2010

The reactions of various
alkyl 5-oxo-2,5-dihydrofuran-2-ylideneacetates and related enol-lactones
with sodium alkoxides in alcohols have been studied.
Four types of compounds have been characterized, each as the major product,
depending on the concentration of alkoxide, the
reaction time and the temperature. 4-Methylcyclopentene-1,3-dione and
4,5-dimethylcyclopentene-1,3-dione have been prepared by short syntheses.
Peptide synthesis with 1-Aminocyclopropane-1-carboxylic acid
Authors: Stewart FHC
Published: September 2010

Peptide derivatives of
1-aminocyclopropane-1-carboxylic acid have been synthesized by model active
ester coupling reactions in order to compare the steric effect of this plant
amino acid with that of its open-chain congener 2-methylalanine. An analogue of
leucine-enkephalin containing the alicyclic amino acid has also been prepared.
The crystal structure of tricaesium tetrabromocobaltate(II) bromide, Cs3CoBr5, at 4.2 K by neutron diffraction
Authors: Figgis BN , Reynolds PA
Published: September 2010

The crystal structure of Cs3CoBr5
[I4/mcm, a 946(1), c 1504(2) pm, U
1.346(7) nm3, Z 4] has been determined at 4.2 K by single-crystal
neutron diffraction methods. The Co-Br bond length is 239.8(2) pm, and the
Br-Co-Br angles of the distorted tetrahedral cobalt environment are 107.58(9)
and 110.43(9)�. The neutron scattering lengths of cobalt and bromine were
found, by least-squares refinement, to be 2.46(2) × 10-15 and
6.78(2) × 10-15 m respectively, relative to a caesium
scattering length of 5.38 × 10-l5 m. The contact distances and
thermal parameters of Cs3CoBr5, when compared with those
from Cs3CoCl5, provide further evidence on the stability
of M3CoX5 salts. The metal ion must be sufficiently large
to adequately fill the large holes in the lattice whose size is determined by
X-...X- contacts.
Regiospecific 1,3-syn elimination in the acid-catalysed reaction of (4aa,5β,8aβ)-5-Acetoxy-8a-methyldecahydronaphthalen-4a-ol
Authors: Coxon JM , Gibson JR
Published: September 2010

The H2SO4-HOAc-Ac2O
catalysed dehydration of (4aα,5β,8aβ)-5-acetoxy-8a-methyldecahydronaphthalen-4a-ol(1)
to give 8a-methyl-cis-l,2,3,4,6,7,8,8a-octahydronaphthalen-1-yl
acetate (2) occursstereospecifically with
loss of the hydrogen at C1. The reaction is interpreted in terms of the
intermediacy of a tight ion pair in which there is sufficient mobility for the
departing oxy-anion to act as base in the removal of the C1 α-proton.
Cyclopentanoids from phenol. VIII. Enantioconvergent routes to chiral prostanoid intermediates
Authors: Gill M , Rickards RW
Published: September 2010

Inversion of alcohol
configurations in hydroxycyclopentenone and cyclopentenol intermediates prepared from the (1S,4S)-3.5,5-trichloro-1,4-dihydroxycyclopent-2-ene-1-carboxylic
acid (2) leads to the same 2-substituted (4R)-4-hydroxycyclopent-2-enone
derivatives of type (3) as have previously been synthesized from the enantiomeric (1R,4R) acid (1). Similarly, the (1R,4R)
acid (1) can be converted into (R)-4-hydroxycyclopent-2-enone
(5), previously obtained from the enantiomeric (1S,4S)
acid (2). The cyclopentenones (3) and (5), which are
important chiral intermediates in prostanoid
synthesis, are thus available from phenol by enantioconvergent
routes.
Studies of Australian soft corals. XXV. Several caryophyllene-based diterpenes from a Nephthea species
Authors: Ahond A , Bowden BF , Coll JC , Fourneron J , Mitchell SJ
Published: September 2010

Two new caryophyllene-based
diterpenes (5) and (6) are reported from the soft coral Nephthea chabrolii. The structures were deduced
spectroscopically and the compounds were converted into several known
diterpenes by chemical transformation. The presence of the caryophyllene
ring system was based on 13C n.m.r. data and confirmed by conversion
into the known clovane ring system by an
acid-catalysed hydration-rearrangement of the endocyclic epoxide (12).
Chemical constitution and activity of bipyridinium herbicides. XV. Synthesis, reduction and biological activity of 4,4'-Azobis(1-methylpyridinium) bis(methyl sulfate)
Authors: Rockley JE , Summers LA
Published: September 2010

4,4'-Azobis(1-methylpyridinium)
bis(methyl sulfate) is reduced in aqueous solution by zinc powder to the
corresponding hydrazo diquaternary salt.
Studies of stab initiation. Sensitization of lead azide by energetic sensitizers
Authors: Spear RJ , Elischer PP
Published: September 2010

A series of 17 compounds
which ignite and explode upon heating have been synthesized. Ignition temperatures
range from 122�
to 261�.
The ability of these compounds to sensitize the primary explosive lead azide to
stab initiation has been determined on 1 : 10 admixtures.
The general trend observed was that stab initiation energies increase with
sensitizer ignition temperature but the overall correlation is poor. An
assessment of the dependence of the ratio of sensitizer to lead azide on stab initiation
energies is also included for two of the compounds. The results are interpreted
in terms of possible mechanisms for the initiation process and support the
hypothesis that frictional processes
are
of primary importance.