bluuebunny/crossref_metadata_2025 huggingface dataset:
The chemistry of pyrrolic compounds. XXII. β-Hydroxyporphyrins and their derivatives
Authors: Clezy PS , Webb NW
Published: September 2010

Several approaches to the synthesis of β-hydroxyporphyrins are described. These tetrapyrroles
are stable only as their dication; under basic or neutral conditions they
rapidly oxidize to give a mixture of products. The structure of one of these
oxidation products has been investigated. Ester and ether derivatives of the
19-hydroxyporphyrins are stable and have been prepared.
The interactions of excited 1,3-Diphenyl-2-pyrazoline with indole and phenol
Authors: Zdysiewicz JR
Published: September 2010

The fluorescence emission
spectrum of 1,3-diphenyl-2-pyrazoline loses its
structured appearance and shifts to lower energies in the presence of indole in n-heptane. There is also a decrease in the
intensity at the maximum fluorescence position. These changes are similar to
those which occur when the diphenyl-pyrazoline is
dissolved in solvents of increasing polarity. They are attributed mainly to a
high concentration of the indole in the solvent shell
of the diphenylpyrazoline and the solvent-shell
reorientation processes which result from an increased dipole moment of the
diphenyl-pyrazoline in the excited state and which
occur in the time interval between absorption and subsequent emission. The NH
group is not necessary for the interaction since l,2-dimethylindole
brings about similar changes in the fluorescence spectrum of the diphenylpyrazoline. In the presence of phenol the
predominant effect is a marked quenching of the fluorescence of the diphenyl-pyrazoline. This is attributed mainly to a hydrogen transfer
mechanism operating between phenol and the diphenylpyrazoline.
Constituents of Eupomatia Species. II. Isolation and Structure Determination of Further Eupomatenoid Lignans From the Bark of Eupomatia laurina
Authors: Bowden B , Ritchie E , Taylor W
Published: September 2010

A further extraction of the
bark of Eupomatia laurina R.Br. has yielded 16 substances: liriodenine (as
before), norushinsunine, three new bases, benzoic acid, sitosterol,
eupodienone-1 (previously EL2; but not EL3 which is an artefact from EL2),
eupomatene (ELl), and seven related substances. ��� The last eight substances, which are
closely related, ere named ?eupomatenoids?. The structures of the eupomatenoids
-2 to -8 have been established. Like eupomatenoid-1 (eupomatene), they are
derivatives of 3-methyl-2-phenyl-5-(E)-propenylbenzofuran and are classified as
lignans.
Bonding in dl0 transition metal complexes. I. Infrared, Raman, and N.Q.R. studies of some dihalocuprate(I) complexes
Authors: Bowmaker GA , Brockliss LD , Whiting R
Published: September 2010

The i.r.
and Raman spectra of the dihalocuprate(1) ions CuX2-
(X = Cl, Br) have been measured in solution, and in a
number of crystalline compounds with large organic cations. The halogen and
copper n.q.r. frequencies of the CuX2-
ions in some of the solid complexes were also measured. In all cases, the ions
were found to have linear, centrosymmetric structures. The various theories
which have been proposed to describe the bonding in linear d10
transition metal complexes are discussed, and it is concluded that the scheme
proposed by Orgel and Jorgensen, involving ds hybridization on the metal atom, best accounts for the n.q.r. results, although some uncertainty is introduced
through the lack of sufficient information concerning the magnitude of the Sternheimer effect. An experiment which might differentiate
between the ds and sp hybridization schemes in the
case of linear AuI complexes is proposed.
Synergistic extraction of uranyl ion with β-diketones and sulphoxides
Authors: Subramanian MS , Pai SA
Published: September 2010

Distribution measurements
of the synergistic extraction of uranyl ion with β-diketones and
sulphoxide donors indicate that the long-chain aliphatic sulphoxides are ten
times more powerful as synergists than the aromatic sulphoxides. Methods of
estimating the relative base strength of the donors by i.r.
and N.M.R. studies of the donor hydrates are described and the results have
been correlated with the equilibrium constant of the synergistic reaction. For
a given sulphoxide donor, the synergistic enhancement seems to be affected by
the various substituents changing the acidity of the β-diketone. From the
values of enthalpy and entropy factors derived for these systems by
distribution measurements at different temperatures, the greater stability of
the complexes with aliphatic sulphoxide donors has been attributed to the
entropy factor.
Complexes of uranyl β-diketonates with sulphoxides
Authors: Subramanian MS , Pai SA , Manchanda VK
Published: September 2010

The proton magnetic
resonance spectra of the synergistic complexes of uranyl β-diketonates with dihexyl
sulphoxide as the neutral donor give a multiplet
consisting of eight lines for the terminal methylene group protons adjacent to
the sulphur atom of the sulphoxide and a triplet for the β-methylene protons.
This conforms to an ABX2 pattern arising as a result of
nonequivalence of the two protons of the terminal methylene group as a result
of steric hindrance to free rotation about the C-S bond. The presence of such
restricted rotation has been adduced as evidence for a direct donor-metal bond.
Diterpenoids. XXXI. Three new resin acids
Authors: Carman RM , Craig WJ , Shaw IM
Published: September 2010

Three new diterpenoid resin
acids have been isolated from Agathis robusta, and their structures are shown to be (1), (6), and
(11).
Vibrational frequencies, force constants, mean amplitudes, shrinkage effects, and Coriolis constants for CF3C≡CX (where X = Cl, Br, and I)
Authors: Augdahl E , Kloster-Jensen E , Devarajan V , Cyvin SJ
Published: September 2010

Harmonic force fields are
developed for 1-chloro-, 1-bromo-, and 1- iodo-3,3,3-trifluoropropyne on the
basis of recent infrared and Raman data. Calculated mean amplitudes of
vibration, Bastiansen-Morino shrinkage effects, and Coriolis coupling constants
are reported.
Diaquabis(diamine)chromium(III) complexes: Acid dissociation constants and isomerization
Authors: Couldwell MC , House DA , Powell HKJ
Published: September 2010

Acid dissociation constants
are reported for the following equilibria:

trans-Cr(A)(B)(H2O)23+(aq) + H2O ↔ trans-Cr(A)(B)(OH)(H2O)2+(aq)+H3O+(aq)
pK1 trans-Cr(A)(B)(OH)(H2O)2+(aq) + H2O ↔ trans-Cr(A)(B)(OH)2+(aq)+H3O+(aq)
pK2

where A = B = en; A = B = tmd; A = en, B = tmd. Similar
results were

obtained
for each complex: pK1 c. 4.2, pK2 c. 7.6; 1M NaNO3,
25�. The results are compared with pK data for related complexes of chromium and cobalt. The
complex Cr(en)2(H2O)(OH)2+ undergoes extensive
Cr-N bond rupture to yield deaminated products.
Monothiocarbonates and their oxidation to disulphides
Authors: Murphy CN , Winter G
Published: September 2010

The preparation,
properties, and oxidation of potassium methyl to hexyl mono-thiocarbonates and
of dipotassium butyl bis(monothiocarbonate) are reported. The oxidation product
of the latter is a dimer. Some nickel, lead, copper, and silver complexes were
isolated. The ability of monothiocarbonates to form metal complexes lies
between alkyl carbonates and dithiocarbonates. Copper(I) ethyl
monothiocarbonate is a tetramer.
Hydroboration of Flav-3-enes, and oxidation to 2,4-trans-Flavan-4-ols, 2,3-trans-Flavan-3-ols, and 1,3-Diarylpropane derivatives
Authors: Clark-Lewis JW , McGarry EJ
Published: September 2010

Hydroboration of
flav-3-enes has been found to be sensitive to electron release from
substituents in the A-ring. Flav-3-enes which lack electron-releasing
substituents in the A-ring give 2,4-trans-flavan-4- ols as the principal non-phenolic
products. Electron-releasing substituents in the A-ring favour boration at the
3-position, and the boranes so formed suffer ring fission, which leads to the
isolation of phenolic 1,3-diarylpropane derivatives as well as
2,3-trans-flavan-3- ols. Ring fission of the intermediate borane is minimized
by reducing the temperature of hydroboration. N.m.r. data are presented on the
compounds obtained.
The optical rotation of tertiary alcohols
Authors: Carman RM
Published: September 2010

Brewster's rules are
modified to deal with the optical rotation of tertiary alcohols.
Monocyclopentadienyltitanium(III) compounds. IV. Carboxylates
Authors: Coutts RSP , Martin RL , Wailes PC
Published: September 2010

Two methods of preparing monocyclopentadienyltitanium(III) carboxylates of general
formula cpTi(O2CR)2 (cp =
π-cyclopentadienyl; R = CF3, CH3, CH2CH3,
CH2CH2CH3, C6H5) have
been investigated. Although titanium(III) has the configuration 3d,1
the green or brown dimers are virtually diamagnetic. The diamagnetism probably
arises from a superexchange interaction between titanium atoms through the π-system
of the carboxylate bridges although the possibility of some direct metal-metal
interaction cannot be excluded at this stage. Spectroscopic data are reported
for all compounds. ��� Bis(cyclopentadienyl)titanium(III) carboxylates
of general formula cp2Ti(O2CR) (R = H, CH3, CH2CH3)
were formed when cpTi(O2CR)2
were vacuum sublimed at c. 180�C.
Enthalpy and entropy changes for formation of nickel(II) complexes with some C-alkylethylenediamines
Authors: Powell HKJ , Curtis NF
Published: September 2010

Enthalpy and entropy data
are reported for the formation of nickel(II) complexes with the ethylenediamine
homologues propane-1,2-diamine and 2-methyl-propane-1,2-diamine. Trends in
ΔH values are related to ligand basicity and to solvation of the complex
ions.
Chemical Studies of the Proteaceae. VI Two Naphthoquinones From Stenocarpus salignus
Authors: Mock J , Murphy ST , Ritchie E , Taylor WC
Published: September 2010

Two pigments,
stenocarpoquinone-A and -B, isolated from the wood of Stenocarpus salignus
R.Br., are shown to be (R)-3?-hydroxy-β-lapachone (1) and
4?-hydroxy-iso-α-lapachone (2), respectively. No pigments could be
obtained from the wood of Stenocarpus sinuatus Endl.
Hydrocarbon constituents of the Argentine ant, Iridomyrmex humilis
Authors: Cavill GWK , Houghton E
Published: September 2010

The 26 hydrocarbons
identified from Iridomyrmex humilis comprise 0.24% of the body weight of the
insect. They include the normal alkanes, C14 to C27, and
a number of alkenes and 3- and 5-monomethylalkanes in the range C14
to C20. The presence of 4-methylhexadecane is noted. Two of the
constituents, heptadecane and (Z)-nonadec-9-ene, comprise 80% of the total.
Tropolones and other products from a Reimer-Tiemann reaction
Authors: Krajniak ER , Ritchie E , Taylor WC
Published: September 2010

The Reimer-Tiemann reaction
on 4-methyl-, 4-ethyl-, and 4-propyl- guaiacols gave the corresponding normal
5-alkyl-2-hydroxy-3- methoxybenzaldehydes together with the minor products:
4-alkyl-4- dichloromethyl-2-methoxycyclohexa-2,5-dienones, 4-alkyl-5- chlorotropolones,
3-alkyl-4-chlorobenzoic acids, 6-alkyl-4-hydroxy-3- methoxybenzaldehydes, and
5-alkyltropolones. The minor aldehydes are formed from the dienones during
workup by a dienone-phenol rearrangement, and the dienones yield the 5-alkyl-tropolones
by the action of alkali. The acids are derived from the chlorotropolones by
base-catalysed ring contraction. The chlorotropolones do not appear to be
derived from the dienones but rather through direct addition of dichlorocarbene
to the phenolate anions.
A paramagnetic species in irradiated Ethane-1,2-diphosphonic acid
Authors: Whelan DJ
Published: September 2010

γ-Irradiation of
powdered and single crystals of ethane-1,2- diphosphonic acid at room
temperature yields three stable free radicals, one in which the unpaired
electron is centred on carbon and two in which it is centred on phosphorus. One
of the phosphorus- centred free radicals is a sigma radical with e.s.r.
parameters g = 1.999, Aiso = 81.4 mT, and 2B = 13.1 mT and is
assigned the structure (HO)2P(0)CH2CH2P.(OH)3.
Vibrational spectra of some Group Vb halides. III. A far-infrared and Raman spectral study of some Hexahalogeno-, Pentahalogeno-, and Tetrahalogeno-bismuthate(III) and -antimonate(III) salts
Authors: Hooper MA , James DW
Published: September 2010

Vibrational spectra of a
series of halogeno-complex ions of antimony(III) and bismuth(III) are reported.
Results of crystal spectra are discussed in terms of the structural environment
and a comparative study of Raman solution and solid state spectra is given.
Some force constants for hexahalogeno species on a modified Urey-Bradley force
field have been calculated and their significance is discussed.
Vibrational spectra of metal-nitro complexes. II. Substituted halo complexes of platinum(IV)
Authors: Nolan MJ , James DW
Published: September 2010

The infrared and Raman
spectra of compounds forming the series given by [Pt(NO2)6-nCln]2-
(n = 0-5) together with some of the analogous bromo and iodo compounds have
been obtained. Most compounds were studied in the solid state, but the Raman
spectra of solutions of some of the compounds were also obtained. The spectra
were interpreted initially by considering the likely point group symmetry of
the complex ion. Where details of the crystal structures were known, the site
group and factor group symmetries were also considered.
N.M.R. spectra of the carbolines. II. 14N quadrupolar and exchange broadening of spectral lines
Authors: Balkau F , Heffernan ML
Published: September 2010

The n.m.r, spectra of
carbazole and the carbolines were previously reported to show unusual line
broadening effects under certain conditions. It is found that for the proton in
position 9 both chemical exchange and 14N quadrupolar relaxation are
responsible for the large line widths observed, while for protons in the ?pyridine?
ring chemical exchange is the more important effect. The nature of this
exchange is still uncertain, the rate being critically dependent on solvent and
sample purity as well as temperature.
The aggregation of the tetrasodium salt of copper phthalocyanine 4,4',4'',4'''-tetrasulphonic acid. Diffusion studies
Authors: Blagrove RJ
Published: September 2010

The effect of urea and
thiourea on the aggregation of copper phthalocyanine-4,4?,4?,4??-tetrasulphonic
acid in aqueous solution has been studied using the capillary diffusion
technique. The addition of excess inert electrolyte was necessary in order that
the measurements were not complicated by facilitated diffusion. The extent of aggre- gation has been estimated
empirically from the dependence of the diffusion coefficient on molecular
weight. The significance of both the changes in diffusion coefficient and the
dissociation of the dye, in relation to dyeing behaviour, is discussed.
The reaction of ethenetetracarbonitrile with acyclic β-dicarbonyl compounds and related studies
Authors: Ducker JW , Gunter MJ
Published: September 2010

The reaction of
ethenetetracarbonitrile (TCNE) with acyclic β- dicarbonyl compounds has
been shown to give 2-dicyanomethylene-2,5- dihydropyrroles (5) via
2-imino-2,3-dihydrofurans (4). Hydrogenation of (5) gave the pyrroles (16).
Representative pyrroles were degraded and synthesized by an alternative route.
The novel transformation of substituted malononitriles to carboxylic acids has
been investigated. The reaction of alcohols with ketone-ethenetetracarbonitrile
adducts has been reinvestigated.
The reaction of 4-Amino-5-aminomethyl-2-methylpyrimidine with amidine salts
Authors: Evans RF , Robertson AV
Published: September 2010

Treatment of
4-amino-5-aminomethyl-2-methylpyrimidine with formamidine salts yields not the
expected dihydropyrimidopyrimidine, but rather its ring-opened hydrate,
4-amino-5-formamidomethyl-2-methylpyrimidine. Other workers had previously
prepared the latter compound by other methods, but had assigned a wrong
structure. The present structure determination is based mainly on i.r., N.M.R.,
and mass spectrometric analysis, as well as examination of the corresponding
acetamido series. Mass spectra include a noteworthy fragmentation process,
expulsion of neutral, even-electron NH.
Square wave frequency modulation in pure nuclear quadrupole resonance spectroscopy
Authors: Caldwell RA
Published: September 2010

The effect of square wave
modulation frequency on the signal intensities obtained with a
super-regenerative spectrometer is investigated. The dependence of the nuclear
quadrupole resonance signal intensity obtained with a number of compounds is
found to be related to the apparent spin-spin relaxation time of the resonant
nuclei. An analysis indicates that the signal response of the resonant nuclei is
the same regardless of modulation frequency. However, the fundamental Fourier
component is directly related to the apparent spin-spin relaxation time.
Use of a particulate bed electrode for the electrochemical investigation of metal and sulphide flotation
Authors: Gardner JR , Woods R
Published: September 2010

An electrochemical cell has
been constructed which utilizes a particulate bed electrode in order to allow
the flotation properties of conducting particles to be correlated directly with
electrode processes occurring at the solid-solution interface. ��� The flotation of gold, lead, and galena
particles with ethylxanthate has been investigated. The general relationships
between flotation characteristics and electrode reactions are found to be the
same with small particles as those previously observed with solid electrodes. ��� For gold the amount of anodically produced
dixanthogen which is needed for flotation is found to be of the order of a
monolayer. Comparison of the behaviour of lead and galena gives an indication
of the possible roles of dixanthogen and lead xanthate in the flotation of
galena.
Diterpene chemistry. III. Transformations of Labda-8(17), 14-Dien-13-ol (Manool)
Authors: Grant PK , Liau HTL , Nicholls MJ
Published: September 2010

The synthesis of an acetal
type perfume from manool is reported. Nuclear Overhauser effect and mass
spectrometry studies on a series of related acetals showed some unusual
spectroscopic properties.
Oxidative cyclizations. III. Kinetic studies of the oxidation of 2,4-dinitroaniline and 2-benzoylaniline with (diacetoxyiodo)benzene
Authors: Dyall LK , Kemp JE
Published: September 2010

For the oxidative
cyclization of 2,4-dinitroaniline and 2- benzoylaniline
with (diacetoxyiodo)benzene in toluene solution, the kinetic orders are unity
in amine and oxidant, zero in iodobenzene and cyclic product, and -1 in
monomeric acetic acid. These characteristic orders are also those observed for
2-nitroaniline and, together with evidence for a specific solvation effect by
acetic acid on the reaction rates of all three amines, indicate that a common
mechanism of oxidative cyclization applies to a range of ortho-substituted
anilines. For 2-benzoylaniline, there is infrared evidence of an N-H bond in an
iodoso intermediate. ��� Equilibrium constants for the monomer
↔ dimer equilibrium of acetic acid in toluene solution have been
determined at four temperatures between 25� and 46�.
The dimerization of anils of pyridine aldehydes catalysed by cyanide ion
Authors: Barnes CS , Halbert EJ , Goldsack RJ
Published: September 2010

The three isomeric
N-(pyridylmethylene)anilines (1; Ar? = pyridyl, Ar = phenyl) dimerized in Me2SO
with NaCN to give the enediamines (2). Only when Ar? = 3-pyridyl did this
spontaneously dehydrogenate to the bis(phenylimino) compound which was
hydrolysed to 3,3?-pyridil. The 4- pyridyl enediamine (2; Ar? = 4-pyridyl, Ar =
phenyl) formed a 1 : 1 adduct with Me2SO. It was oxidized in poor yield
to the stable bis(phenylimino) compound. The 2-pyridyl enediamine (2; Ar? = 2- pyridyl,
Ar = phenyl) was oxidized with chloranil. Under standard conditions attempted
dimerization of (1; Ar? = 4-pyridyl, Ar = 4- methoxyphenyl) gave a [(4?-methoxyphenyl)imino](4-pyridyl)acetonitrile
(7). ��� A series of monophenylimino derivatives of
2,2?-pyridil, and some anilides of isonicotinic acid, were prepared.
A new synthesis of 1-Benzyl-1,2,3,4-tetrahydroisoquinoline
Authors: Deady LW , Pirzada NH , Topsom RD , Bobbitt JM
Published: September 2010

The synthesis of
N-(2-bromoethyl)-N-(1,2-diphenylethyl)ammonium bromide and its aluminium
chloride catalysed decomposition to 1-benzyl-1,2,3,4- tetrahydro-isoquinoline
is described.
Synthesis of ar-nitrostyrenes
Authors: Butcher M , Mathews RJ , Middleton S
Published: September 2010

The title compounds are
conveniently prepared in high yield by reaction of the appropriate
nitrobenzylidenetriphenylphosphorane with aqueous formaldehyde.
The reaction of acid anhydrides, dibasic acid diesters, and dibasic acids with vinylmagnesium chloride
Authors: Suga K , Watanabe S , Fujita T , Takahashi Y
Published: September 2010

The reaction of acid
anhydrides, dibasic acid diesters, and dibasic acids with vinylmagnesium
chloride yields mixtures of alkenones, hydroxyalkenones, and alkenols as the
main products.
Synthesis of robustol trimethyl ether
Authors: Cannon JR , Metcalf BW
Published: September 2010

The macrocyclic substance
robustol trimethyl ether (2) has been synthesized by an unambiguous method. ��� During a study of the reactions of model
compounds a new synthesis of 1,14-bis-(3?,5?-dimethoxyphenyl)tetradecane (4)
has been developed.
Circular dichroism spectra of asymmetric unidentate amine complexes of cobalt(III)
Authors: Hawkins CJ , Lawrance GA
Published: September 2010

The preparations of pentaamminecobalt(III) complexes of a series of asymmetric
unidentate amines are reported. The circular dichroism spectra for the
(S)-amines show negative Cotton effects under the 1A1g
→ 1T1g absorption band, which are somewhat solvent dependent
but independent of temperature down to -190�C. The vicinal effect from 1- cyclohexylethylamine
was comparable to that from analogous aromatic compounds, but the simpler alkyl
derivatives were found to impose smaller rotational strengths on the d-d
transitions. The lack of measurable c.d. in the visible region for tetraammine((S)-butane-1,3-
diamine)cobalt(III) is reported and discussed in the light of the other
studies.
Heats of sublimation of phthalocyanines
Authors: MacKay AG
Published: September 2010

Heats of sublimation for
tin, dihydrogen, vanadyl, zinc, nickel, palladium, platinum, lead, molybdenum,
copper, cobalt, and iron phthalocyanines are given. Decomposition of manganese
phthalocyanine prevented a determination. Selected refractive indices are also
reported and the trends in the heat of sublimation data are discussed in terms
of the influence of the metal on the electron density of the peripheral
nitrogens of the phthalocyanine ring and the associated intermolecular
interactions.
A revision of the structures proposed for the melicope extractives, melicopol and methylmelicopol
Authors: Balgir BS , Mander LN , Mander STK
Published: September 2010

2,4,6-Trihydroxybenzoic
acid was converted by partial methylation, formylation, and then reduction into
methyl 2-hydroxy-3-hydroxymethyl- 4,6-dimethoxybenzoate (5) which proved different from dimethyldegeranylmelicopol. Methyl 6-geranyloxy-2-hydroxy-3-
hydroxymethyl-4-methoxybenzoate (4), its neryl analogue (7), and methyl 4-geranyloxy-2-hydroxy-3-hydroxymethyl-6-methoxybenzoate (21) were prepared
similarly but all were different from methylmelicopol. From a re-investigation
of earlier work, melicopol and methylmelicopol were assigned new structures,
6?-geranyloxy-2,2?,4?-tri-hydroxy-3?- methoxyacetophenone
(31) and its 4?-methyl ether derivative (24), respectively. Dimethyldegeranylmelicopol,
2,6?-dihydroxy-2?,3?,4?- trimethoxyacetophenone (25),
was prepared from antiarol (28) and acetoxyacetonitrile.
A study of hydroxyl participation in acyclic epoxide systems. Acid-catalysed rearrangements of trans- and cis-3,4-Epoxypentan-1-ols, 4,5-Epoxyhexan-1-ols, and 5,6-Epoxyheptan-1-ols
Authors: Coxon JM , Hartshorn MP , Swallow WH
Published: September 2010

The acid-catalysed
rearrangements of trans- and cis-4,5-epoxyhexan-1- ols
and 5,6-epoxyheptan-1-ols demonstrate a preference
for cyclic ether formation: tetrahydrofuran > tetrahydropyran > oxepan.
The ether products arise by intramolecular hydroxyl displacement of the epoxide
oxygen with inversion of configuration. Reactions of trans- and cis-
epoxypentan-1-ols give a mixture of trans- and
cis-2-methyl-tetrahydro- furan-3-ols (8) and (9).
From each epoxide one methyltetrahydrofuranol must arise by nucleophilic
displacement of the secondary epoxide oxygen with retention of configuration.
Alkoxyl migration in the mass spectra of the esters of arylsulphonylacetic acids
Authors: Pratanata I , Williams LR
Published: September 2010

When subjected to electron
impact esters of arylsulphonylacetic acids eliminate ketone by an alkoxy
migration to the ortho position of the ring.
Search for surface structural effects in electrocatalysis. I. Smooth platinum electrodes
Authors: Biegler T
Published: September 2010

Platinum electrodes were
pretreated in various ways with the aim of producing surfaces of different
structure. The adsorptive properties were studied using linear sweep voltammetry,
and the activity for the anodic oxidation of methanol was determined using a
multi-pulse potential program. Although chemical etching and different kinds of
heat treatment altered the hydrogen adsorptive properties of platinum, the
specific activity for methanol oxidation was not significantly affected. A
relationship between the shapes of anodic voltammograms in the hydrogen region
and at the start of the oxide region was noted and used in deducing the nature
of the adsorbed oxygen-containing species and its involvement in the methanol
oxidation reaction. Electro- chemical activation of cold-worked electrodes was
attributed to the removal, by anodic dissolution, of a structurally disturbed
layer of surface platinum atoms of lower activity than a crystalline surface.
The activity of platinum for methanol oxidation was concluded to be a property
of a well-ordered crystalline surface, independent of orientation.
Tumour inhibitory plants. New alkaloids from the bark of Erythrophleum chlorostachys (Leguminosae)
Authors: Loder JW , Culvenor CCJ , Nearn RH , Russell GB , Stanton DW
Published: September 2010

A new alkaloid,
norerythrostachamine (1), and its rearrangement product, norerythrostachamide
(2), from extracts of E. chlorostachys bark,
are shown to be the ester and amide of 2-methylaminoethanol and 3β,7β-dihydroxycass-13(18)-en-16,19-dioic
acid 16-methyl ester already known from borohydride reduction of erythrophlamic
acid. A second isomeric pair, norcassamidine (3) and norcassamidide (4),
derived from 2-methylaminoethanol and cassamidic acid, are described as well as
a new amide, norcassaidide (9, formed from the same amine and cassaidic acid.
The known alkaloids cassaidine (6), cassamidine (7) and norerythrophlamide (8)
were also isolated.
Fluorescent whitening agents, I. Bis-4,4'-(4''-methoxy-6''-phenoxy-s-triazin-2''-ylamino)stilbene-2,2'-disulphonic acid : Its photodecomposition in solution and on wool
Authors: Milligan B , Holt LA
Published: September 2010

The collidine
salt of bis-4,4'-(4"-methoxy-6"-phenoxy-s-triazin-2?-ylamio)stilbene-2,2'-disulphonic
acid (1) has been synthesized from cyanuric chloride.
Anhydrous conditions were used so as to avoid contamination by hydrolysis
products; the methoxyl groups were radioactively labelled. Irradiation of the
trans (E) isomer of (I) in aqueous solution rapidly produced an equilibrium
mixture of cis (Z) and trans isomers; decomposition to the
corresponding aldehyde (2), acid (3) and dihydro
derivative (4) occurred more slowly. Isomerization to the cis form was much slower when (1) was applied to wool and then
irradiated; (2), (3) and (4) were also produced and some radioactive material
was bound covalently to the wool. No evidence could be obtained for the conversion
of (1) into phenanthrene or cyclobutane
derivatives or for the occurrence of any photo-Fries rearrangement.
Nuclear magnetic resonance studies of Lewis acid-base interaction. I. Base adducts of Bis(ethylxanthato)nickel(II)
Authors: Lim Yau Yan.
Published: September 2010

The interaction between
bis(ethylxanthato)nickel(11) and pyridine and
4-picoline in nitrobenzene was studied by N.M.R. spectroscopy at 34�C. The 1 :
2 equilibrium constants and proton n.m.r, isotropic contact shifts were
obtained. The electron spin delocalization mechanism in the 1 : 2 adduct was discussed.
Reactions of trifluoromethyl radicals. III. Hydrogen abstraction from methyl trifluoroacetate, methyl pentafluoropropionate and methyl heptafluorobutyrate
Authors: Arthur NL , David LF
Published: September 2010

Hydrogen abstraction from
CF3COOCH3, C2F5COOCH3
and C3F7COOCH3 by CF3 radicals has
been studied in the temperature range 100-210�. The rate constants, based on
the value of 1013,36 cm3 mol-1 s-1 for the
recombination of CF3 radicals, are given by (kn
in cm3 mol-1s-1, E in kJ mol-1, R = 0.008314 kJ K-1 mol-1):

Logk1 = (10.81 �
0.16)-(37.52 � 1.27)/2.303RT

Logk2 = (10.93 �
0.16)-(38.80 � 1.32)/2.303RT

Logk3 = (11.24 �
0.08)-(42.49 � 0.63)/2.303RT

The reactivity of the
methoxyl groups in these esters is less than those in HCOOCH3 and CH3COOCH3
by a factor of between 2 and 3. This can be explained in terms of
intermolecular polar repulsion induced by the fluorine atoms in the esters and
the CF3 radical.
Some Constituents of the Resins of Xanthorrhoea preissii, australis and hastile
Authors: Birch AJ , Dahl CJ
Published: September 2010

Examination of the above
resins has revealed the presence apart from polymeric material of a number of
hydroxy- and methoxy-flavanone derivatives, some
derivatives of 2-methyl-2,3-dihydronaphtho-[1,8-bc]pyran-5-ol (1), C6C3
derivatives such as cinnamyl alcohol and p-coumaric
acid, and chrysophanic acid. The inflorescence of X. australis
contains no flavonoids, but p-coumaric acid, chryso-
phanic acid and aloeemodin.
Two dimeric flavonoids are isolable from X. preissii.
Reported occurrences of compounds in all Xanthorrhoea resins are
summarized and some of the implications discussed. The 'red' and 'yellow'
resins differ markedly; X. hastile contains no naphthopyran
derivatives and the resin is chiefly a polymer. Despite the large number of
compounds reported (Table 1) only a small proportion of the resins has been
accounted for as isolated pure substances.
Spectra of azulene dimers
Authors: Ferguson J , Mau W , Morris JM
Published: September 2010

Spectra of stable dimers of
azulene in an isopentane-methylcyclohexane glass at 77 K are reported. In the
700 nm region the dimer spectrum shows a marked hyperchromism and blue shift of
100 cm-1 compared to the monomer. Assumption of a stacked
'head-to-tail' configuration for the dimer and use of the dipole-dipole
approximation enables the spectral shift to be accounted for. In the U.V.
region, a large loss of intensity is observed for the S2 ← So
and S3 + So transitions and a number of new dimer bands
are observed. The intensity redistribution is assigned to configuration mixing
of the monomer states in the dimer. No luminescence could be observed from the
dimer.
Aromatic nucleophilic substitution with sulphoxides: The interaction of dimethyl sulphoxide with chloronitrobenzenes
Authors: Biffin MEC , Paul DB
Published: September 2010

Activated chlorine atoms
are displaced by sulphoxide oxygen when di- and tri-nitrochlorobenzenes
are heated in dimethyl sulphoxide. The corresponding
phenols, thiomethoxymethyl- and formyl-
substituted phenols, thioanisoles and decomposition
products of chlorodimethyl sulphide
are formed. Monochloronitrobenzenes do not undergo
reaction with Me2SO even at 190�, but in the presence of added
sodium acetate or sodium benzoate, phenols and thioanisoles
are obtained together with products derived from the sulphonium
ylid CH3S+=CH2.
These observations are rationalized mechanistically. The reaction mixtures are
shown to oxidize benzyl alcohol to benzaldehyde. These results do not
substantiate the presence of an intermediate sulphonium
complex, however, because benzyl alcohol competes more favourably
for the chloroaromatic system than does Me2SO;
benzyl alcohol forms the chloride which then undergoes a Kornblum oxidation to
yield benzaldehyde.
Reduction by sulphoxides : The mechanism of deoxygenation of heterocyclic N-oxides and tertiary amine N-oxide
Authors: Biffin MEC , Bocksteiner G , Miller J , Paul DB
Published: September 2010

Heterocyclic and tertiary
amine N-oxides undergo an
acid-catalysed deoxygenation by sulphoxides
at elevated temperatures. The reductions are rationalized by postulating the
formation of an initial coordination complex formed by attack of the
nucleophilic N-oxide oxygen atom on
the sulphur atom of the sulphoxide
or its conjugate base. This complex may undergo an internal redox reaction to
give a sulphone and amine or alternatively be
attacked by a nucleophilic species (presumably sulphoxide
oxygen) to produce a sulphinate and amine. Both
decomposition pathways were observed. Deoxygenation
of heterocyclic N-oxides, however,
proceeds primarily by the second route and that of aliphatic amine oxides by
the first decomposition process. These observations are rationalized
mechanistically. The effect of varying the N-oxide
substrates and the sulphoxides has also been
examined.
Reactions of copper in molten alkali-metal nitrite
Authors: Temple RB , Thickett GW
Published: September 2010

When molten NaNO2
is electrolysed between copper electrodes, a yellow
precipitate which contains copper(1) forms at the cathode.It seems probable that a cuprite with the empirical formula Na2O,Cu2O,H2O
is initially formed and is then slowly oxidized either by species present in
the melt or by air. If sufficient Na2O2 is added to
saturate the melt (i.e., solid Na2O2 is present),the
precipitate partly dissolves to form an orange-red solution which forms a green
solid on freezing. This may contain a copper(11) or copper(111) cuprate.
Solvation of ions. XXII. Solvation of cations by hard N,N-dimethylformamide and soft N,N-dimethylthioformamide
Authors: Alexander R , Owensby DA , Parker AJ , Waghorne WE
Published: September 2010

The free energies of
transfer of some univalent cations from N,N-dimethylformamide
to N,N- dimethylthioformamide
at 25� are Li+, 64.0; Na+, 50.2; K+, 37.2; Cs+,
23.4; TI+, -4.2 and Ag+, - 87.0 kJ g-ion-1.
The values are based on the assumption of negligible liquid junction potential
in an electrochemical cell. Certain ones of these values can be interpreted in
terms of general interactions of hard and soft cations with hard and soft basic
solvents. A linear free energy relationship, ΔGtr(M+)
= mΔGtr(K+), is
roughly obeyed by many cations for transfer to a variety of solvents.
Deviations from this relationship, for example ΔGtr(Ag2+)
to acetonitrile, ΔGtr (Ph4As+)
to water and ΔGtr (Ag+) to
N,N-dimethylthioformamide,
allow specific solvation mechanisms to be detected.
Metal complexes of 1,10-Phenanthroline derivatives. VII. Complexes of 1,10-Phenanthroline-2-carbaldehyde hydrazones
Authors: Goodwin HA , Mather DW
Published: September 2010

A series of substituted
hydrazones derived from 1,l0-phenanthroline-2-carbaldehyde and their bis-ligand
complexes with bivalent iron and nickel are described. The hydrazones show a
gradation in field strength and this is reflected in the spin-state of the iron
complexes. The methylhydrazone complex is essentially
low-spin over the temperature range 83-363 K but the presence of some spin-free
species at high temperatures is evident. Within the same range the dimethylhydrazone complex is essentially high-spin but
undergoes significant spin-pairing and the phenylhydrazone
complex displays a complete 5T2 → 1A1
spin transition. This transition is very sharp, resulting in a pronounced
change in the magnetism, and colour, of the complex
within a few degrees. Complexes of the 2-pyridylhydrazone, the methylphenylhydrazone and the diphenylhydrazone
are high-spin over the entire experimental temperature range.
Donor-acceptor complexes formed by perfluoro-organo bromides and iodides with nitrogenous and other bases. III. Qualitative examination of condensed phase spectra of CF3I and CF3Br and of their complexes with trimethylamine and other bases
Authors: Cheetham NF , McNaught IJ , Pullin ADE
Published: September 2010

This paper reports the spectra of (i) CF3I, CF3Br and N(CH3)3 as solutions in carbon tetrachloride at
room temperature, as liquids at lowered temperatures and as solid films at 80 K and (ii) equimolar
solutions of CF3I and N(CH3)3 in carbon tetrachloride at room temperature, equimolar liquid
mixtures of CF3I and N(CH3)3 at both room and lowered temperatures and annealed solid films at
80 K of CF3I-N(CH3)3 and CF3Br-N(CH3)3. The spectra clearly show the existence of complexes
to which, on the bases of evidence reported in Part I, we assign the structures CF3I.N(CH3), and
CF3Br.N(CH3),. Differences between the spectra of the complexes and the spectra of the free
components for the same phase include (a) the appearance in the spectrum of the complex of a low
frequency band which we attribute to the N-I or N-Br stretching mode, (b) a strong band at a lower
frequency than the carbon-halogen stretching mode in CF3I or CF3Br which we assign to the modified
carbon-halogen stretching mode in the complex, much enhanced in intensity, (c) an increased
frequency of the symmetric carbon fluorine stretching mode and a decreased frequency of the degener-
ate carbon-fluorine stretching mode in the complex compared with the free components, (d) increase
in intensity and frequency of v7 (CNC symmetric bend) of trimethylamine, (e) doubling of several
C-H stretching frequencies. The dependence on phase of the magnitudes of the differences in
frequencies of corresponding modes in the complex and free components are solid (80 K) > liquid ≈
solution in CCI4 > vapour phase. Some details of complexes of CF3I and CF3Br with some other
electron donors are reported briefly.
Donor-acceptor complexes formed by perfluoro-organo bromides and iodides wlth nitrogenous and other bases. V. Comparison of liquid phase complexes of CFI3, C2F5I or C3F7I with Nme3, NEt3 or NPr3; infrared, far-infrared and N.M.R. spectra
Authors: McNaught IJ , Pullin ADE
Published: September 2010

Equimolar liquid mixtures
of CF3I, C2F5I or C3F7I
and NMe3, Net3 or NPr3 were examined by
infrared, far-infrared and N.M.R. spectroscopy. In the liquid mixtures of the
halides with NMe3 or Net3 a broad absorption band at
respectively c. 100 cm-l or c.75
cm-1 was observed, which is assigned to the N-I stretching mode of
the intermolecular complex, analogous to the complexes described in Parts 111
and IV. The fluorine resonances in CF3I and in the ?CF3I
groups are shifted markedly upfield in the equimolar liquid mixture compared to
the liquid halide. Upfield shifts caused by the amines are in the order NMe3
> Net3 > NPr3. Infrared frequency shifts suggest
that NMe3 forms stronger complexes with these halides than does NEt3.
Metastable polymorphs of γ-TNT
Authors: Chick MC
Published: September 2010

Some properties of a new
metastable polymorph of γ-TNT are reported and its stability relationship
with previously reported forms is discussed. It is concluded that γ-TNT is
a monotropic system at ambient pressure.
19F N.M.R. spectroscopy. III. The fluoroformyl group
Authors: Della EW , Rizvi SQA
Published: September 2010

The fluorine-19 nuclear
magnetic resonance spectra of a representative group of cyclohexanecarbonyl
fluorides have been measured in order to test the suitability of fluorine as a
probe for assigning the configuration of carboxyl groups. The data also lead to
an evaluation of the conformational energy of the fluoroformyl group.
Chemistry of pyrrolic compounds. XXVII. Some aspects of the mass spectra and chemistry of meso-substituted porphyrins
Authors: Clezy PS , Lim Cl , Shannon JS
Published: September 2010

Characteristic
fragmentations have been observed in the mass spectra of some meso-substituted porphyrins, and especially in some meso-oxy derivatives. meso-Substituted octaethylporphyrins generally underwent thermal
decomposition in the mass spectrometer; this resulted in the formation of the
parent porphyrin from which the successive loss of eight methyl radicals was
observed. Attempts to prepare meso-carboxyoctaethylporphyrin by oxidation of the formyl derivative or by hydrolysis of the meso-cyano
compound failed. As a by-product of the preparation of meso-cyano- octaethylporphyrin a
porphyrin isocyanide was obtained. Some aspects of
the chemistry of this novel porphyrin derivative are reported together with the
preparation and properties of an oxyporphyrin
substituted with acetic ester side chains.
Positron annihilation and electron densities in organic liquids
Authors: Brown BJ
Published: September 2010

The effective electron
density for positron annihilation in substituted aliphatic and aromatic liquid compounds
has been determined. For the aliphatic hydrocarbons the molecular electron
density Ne
increases linearly with an increase in chain length and is equal to the sum of
the partial electron densities of the substituent methyl (Ne(CH3)
= 1.18) and methylene (Ne(CH2)
= 1.28) groups.The values are
approximately 10% lower for aromatic systems. The partial electron densities of
substituted halogen atoms increase with atomic number and are: fluorine (9.3),
chlorine (10.0), bromine (14.4) and iodine (23.0). For the aliphatic alcohols
the partial Ne(OH) value decreases from
1.35 in methanol to 0.86 in octanol.
The solid state isomerization and thermal decomposition of pentamminethiocyanatocobalt(III) salts [Co(NH3)5SCN] X2 (X = Cl, SCN)
Authors: Snow MR , Thomas RJ
Published: September 2010

Radiochemical tracer
experiments show that in the thiocyanate complex, [Co(NH3)5SCN]
[SCN]2, thermal isomerization to the isothiocyanate
salt proceeds with incorporation of anionic thiocyanate. At least 45% of the
isomerization process proceeds by a dissociative path. This contrasts with the
mechanism in water solution where isomerization occurs without exchange with
thiocyanate in solution. The result also shows the inadequacy of the generally
made assumption that isomerization in the solid state is an intramolecular
process. The chloride and thiocyanate salt were subjected to simultaneous thermogravimetric analysis and differential scanning calorimetry. The thiocyanate salt deamminates
at a much lower temperature (from 100�C) than the chloride (from 160�C), but no
process corresponding to the isomerization could be detected.
Kinetics of the hydrolysis of acetic anhydride and the reaction of 4-nitrophenyl acetate with imidazole in aqueous-organic mixed solvents
Authors: Oakenfull DG
Published: September 2010

With the general aim of
elucidating the role of water structure in the kinetics of hydrolysis, a comparative
study has been made of the kinetics of the hydrolysis of acetic anhydride and
the reaction of 4-nitrophenyl acetate with imidazole in mixtures of water with
ethanol, t-butyl alcohol, dimethyl sulphoxide and dioxan. Both rate constants were always reduced by the
addition of organic solvent. Transition state activity coefficients were
measured for both reactions in dimethyl sulphoxide-water
mixtures and compared with the activity coefficient of phenylalanine (a model zwitterionic transition state). Activation parameters were
measured for the hydrolysis of aceticanhydride in t-butyl
alcohol-water and dimethyl sulphoxide-water mixtures.

Semilogarithmic plots of rate constant against Winstein's
Y-value were non-linear for some of the
solvents and this fact, coupled with the effect of dimethyl sulphoxide
on the transition state activity coefficients, leads to the conclusion that
specific interactions of the solvent with the reactants and with the transition
state could be of major importance in controlling the reaction rate.There was no obvious
relationship between the effect of an organic solvent on the kinetics of hydrolysis
of acetic anhydride and its effect on the structure of water.
C-Methylation of alcohols by trimethylaluminium
Authors: Harney DW , Meisters A , Mole T
Published: September 2010

Tertiary alcohols and aryl
alkyl carbinols are C-methylated by
excess trimethylaluminium, mostly at temperatures in the range 100-200�. Thus
t-butyl alcohol gives neopentane, 1,l-diphenylethanol gives
2,2-diphenylpropane, 2-phenylpropan-2-ol gives t-butylbenzene, and tri-p-ethoxyphenyl- methanol gives
l,l,l-tri-p-ethoxyphenylethane. 1-Methyladamantane is
obtained from adamantan-1-ol and excess trimethylaluminium or by pyrolysis of
dimethylaluminium 1-adamantyl oxide. l,l,l-Triphenylethane is obtained from tri-phenylmethanol
and excess trimethylaluminium (at temperatures as low as 60�), by pyrolysis of
dimethylaluminium triphenylmethoxide, or by reaction of triphenylmethyl dimer
with various methylmetallic compounds. Catalysis and other mechanistically
significant features of the new 'exhaustive methylation' are discussed, and
experimental procedures for the use of alkylaluminium compounds in the organic
laboratory are described.
Exhaustive C-methylation of carboxylic acids by trimethylaluminium: A new route to t-butyl compounds
Authors: Meisters A , Mole T
Published: September 2010

Carboxylic acids are
exhaustively C-methylated to t-butyl compounds by excess trimethylaluminium at
c. 120�. Benzoic acid for example, gives t-butylbenzene. Similarly methylated
are o-fluoro-,
o-bromo-, and m-chloro-benzoic acids, 5-chloro-3-phenylsalicylic acid,
1-naphthoic acid, palmitic, oleic and undec-10-enoic
acids. Adamantane-1-carboxylic acid gives mostly l-isopropenyladaman-
tane, along with some 1-t-butyladamantane. Cinnamic acid gives mainly the allylically
rearranged 2-methyl-4-phenylpent-2-ene. Triphenylacetic
acid behaves atypically; 1,1,1-triphenylpropan-2-one and 3,3,3-triphenylpropyne
result.
Activation of saturated hydrocarbons by homogeneous metal catalysts : Deuterium exchange in iridium(III) solution
Authors: Garnett JL , Long MA , Peterson KB
Published: September 2010

Isotopic hydrogen exchange
between simple alkanes and D2O is
homogeneously catalysed by sodium chloroiridite at
160�C. Initial isotope orientation favours hydrogen
on the primary carbon atoms.High M values for the exchange are typical.
2-Aminothiazole, acetylaminothiazole, dimethylhydantoin and thiohydantoin complexes of tin(IV) and titanium(IV) halides
Authors: Singh PP , Shukla UP
Published: September 2010

Complexes of the type MX4L2
(M = Sn, Ti; X = Cl, Br, I;
L = dimethylhydantoin, thiohydantoin,
2-aminothiazole and 2-acetylaminothiazole) have been prepared and
characterized. Infrared spectral studies indicate exocyclic nitrogen of
2:aminothiazole and carbonyl oxygen of all other ligands as the donor site.
Far-infrared spectra suggest that dimethylhydantoin
and 2-acetylaminothiazole complexes are trans,
and 2-aminothiazole and thiohydantoin complexes are cis octahedral.
Chiral transtion metal complexs containing the ligand (S,S)-2,7-Diisopropyl-3,6-diazaoctanedioic acid
Authors: Magee RJ , Mazurek W , O'Conner MJ , Phillip AT
Published: September 2010

Complexes of the ligand
(S,S)-2,7-diisopropyl-3,6-diazaoctanedioic acid [(S,S)-ebv]
with cobalt(111), nickel(11), palladium(11) and copper(11) are reported and
structural assignments are made on the basis of spectroscopic data. The complex
[Co{(S,S)-ebv}(en)]+ has been isolated as
the trans(O) isomer with a Δ
absolute configuration, as indicated by the c.d. spectrum. The Ni[(S,S)-ebv] complex appears to have an octahedral structure which
is attributed to the bidentate character of the carboxylate groups. The
Pd[(S,S)-ebv] complex contains an uncoordinated carboxylate
group having the fourth coordination site of a square-planar structure occupied
by either a bidentate carboxylate group or a water molecule. The c.d. spectrum
of Cu[(S,S)-ebv] conforms to the general pattern of
copper-amino acidato complexes by having a negative
dominant c.d. band-the collective vicinal effect of the asymmetric nitrogen
donor atoms does not oppose the remaining symmetric influences in the molecule.
rates of N-methylation of 2-Methybenzotriazole, 2,1,3-Benzoxadiazole, 2,1,3-Benzothia(or Selena)diazole, 1,2,5-Oxadiazole and 1,2,5-Thiadiazole
Authors: Davis M , Deady LW , Homfeld E
Published: September 2010

The rates of quaternization of the title compounds with dimethyl sulphate are reported. The reactivity order is Se > NMe > S > O; benzofusion
has only a small rate-diminishing effect.