bluuebunny/crossref_metadata_2025 huggingface dataset:
Diazabenzenes. II. Synthesis, Photolysis and Mass Spectra of Some Tetraalkylpyrazines
Authors: Bell DJ , Brown IR , Cocks R , Evans RF , Macfarlane GA , Mewett KN , Robertson AV
Published: September 2010

2,3,5,6-Tetramethyl-,
tetraethyl- and tetraisopropyl-pyrazines were obtained by fusion of ammonium
acetate with the appropriate acyloin or reduction of the α,α'-diketone
dioxime with zinc dust and alkali. Photolysis of a cyclohexane solution of
tetraisopropylpyrazine led inter alia
to formation of bicyclohexyl. Photolysis of an aqueous solution of tetramethylpyrazine
containing sodium borohydride caused complete reduction of the pyrazine ring to
the hexahydro stage. The high-resolution mass spectra of these pyrazines are
discussed and explained in the light of deuterium labelling and metastable
defocusing information.
The Synthesis and Reactions of N-Hydroxyparacetamol (N,4'-Dihydroxyacetanilide)
Authors: Healey K , Calder IC
Published: September 2010

The synthesis of N-hydroxyparacetamol
(N,4'-dihydroxyacetanilide) is
reported where a copper complex of the hydroxamic
acids as a protecting group is used. It has been shown to decompose between pH
7 and 12 to give products which are derived from N-acetyl-p-benzoquinone imine.3'-Substituted
4'-hydroxyacetanilides are formed when a nucieophile
is present. The properties of
N-hydroxyparacetamol
are consistent with it being the toxic, reactive intermediate involved in the hepatoxicity of paracetamol.
Synthesis and Biological Evaluation of Tetrahydroisoquinolin-4-ol Derivatives
Authors: Quessy SN , Williams LR
Published: September 2010

This paper reports the
synthesis of 4-hydroxytetrahydroisoquinolines which may be regarded as cyclic
analogues of phenylethanolamines.
Isolation of Some Novel Diterpenes from a Soft Coral of the Genus Lobophytum
Authors: Dunlop RW , Wells RJ
Published: September 2010

The isolation and
structural determination of five novel diterpenes (5)-(9) from a soft coral of
the genus Lobophytum
is reported. Also, the sesquiterpenes β-elemene
and germacrene-A and the cembrane
derivative (16) have been isolated and identified.
2-O-Methylobtusatic Acid, a New Depside from the Lichen Xanthoparmelia tusconensis
Authors: Chester DO , Elix JA
Published: September 2010

The depside,
2-O-methylobtusatic acid
[4-(2',4'-dimethoxy-3',6'-dimethylbenzoyloxy)-2-hydroxy-6-methylbenzoic acid]
has been prepared by unambiguous synthesis and shown to co-occur with usnic acid and diffractaic acid
in the lichen Xanthoparmelia tusconensis.
The Chemistry of Aryllead(IV) Tricarboxylates. Reaction with Phenols
Authors: Bell HC , Pinhey JT , Sternhell S
Published: September 2010

A mixture of mesitol (l), p-methoxyphenyllead triacetate (2) and
pyridine in equimolar quantities in chloroform gives an almost quantitative
yield of the 6-arylcyclohexa-2,4-dienone (3) and the 4-aryl-cyclohexa-2,5-dienone (4) in a ratio of 4 : 1. Examination of the effect of
substituents on the reaction has shown that with methylated phenols it only
proceeds in high yield when both ortho
positions are substituted, while the reaction fails with phenols bearing only
electron-withdrawing groups. There is a marked preference for ortho arylation and a preference for
attack ipso to a methoxyl group
compared with methyl groups. 2-Methyl-1-naphthol was the only polynuclear
phenol examined, and it reacted in the expected manner to give the
2-arylnaphthalen-1(2H)-one (24).
Excess Volumes and Isentropic Compressibilities of Binary Mixtures of Butylamine and Cyclic Ketones
Authors: Sreenivasulu M , Naidu PR
Published: September 2010

Excess volumes and
isentropic compressibilities for the binary mixtures of cyclohexanone,
cylopentanone and 2-methylcyclohexanone with butylamine were determined at 303�15
and 313�15 K. Excess volumes of the three mixtures are negative over the whole
range of compositions at both the temperatures. Deviations in isentropic
compressibility are also negative in all the three mixtures. The results are
ascribed to strong hydrogen bonding between unlike molecules. The results also
suggest that cyclization decreases both √E and the deviation
in isentropic compressibility.
On the Reaction of ortho-Diphenoquinone Valence Isomers with Primary and Secondary Amines. X-Ray Structure Analysis of a 2,3-Dihydro-1H-azepinone and its Photochemical and Oxidative Conversion Products
Authors: Becker H , Gustafsson K , Raston CL , White AH
Published: September 2010

Single-crystal X-ray
diffraction structure determinations are reported for three reaction products
and photoisomers formed from reactions between an o-diphenoquinone valence isomer and primary and secondary amines,
namely: 3,5-di-t-butyl-7-(3,5-di-t-butyl-2-hydroxyphenyl)-1-methyl-2,3-dihydro-1H-azepin-2-one (8; R1 = R2
= But, R3 = Me), its photochemical isomerization product
4,6-di-t-butyl-1-(3,5-di-t-butyl-2-hydroxyphenyl)-2-methyl-2-azabicyclo[3,2,0]hept-6-en-3-one
(9; R1 = R2 = But, R3 = Me) and 4',5,7-tri-t-butyl-3'-(2,2-dimethylpropionyl)-1'-methylspiro[benzofuran-3(2H)-2'-
pyrrolidinel-2,5'-dione (12; R1 = R2 = But, R3
= Me).
Heterocyclic Compounds from Alloxan and Amines. XIV. Structure of Even-Electron Products Derived from Free-Radical Betaines
Authors: Clark-Lewis JW , Taylor MR , Westphalen J
Published: September 2010

X-ray crystallographic
determination of structure has shown that the even-electron product obtained
thermally from 5-(10-phenyl-5,10-dihydro-5-phenazinioyl)-1,3-dimethyl-4-barbiturate
(1) (e.g. by heating in benzene) has the structure 1,3-dimethy1-5-(10-phenyl-2,10-dihydrophenazin-2-ylidene)-
hexahydropyrimidine-2,4,6-trione (3) instead of the previously supposed dehydro
dimer structure (2). Crystals of compound (3) are triclinic, Pī, a 11�014(3), b 9�343(3), c 10�927(3) �, α 110�47(4), β 64�99(4), γ 101�47(4)�, Z = 2. Full-matrix least-squares refinement gave
R 0�09. The rearrangement that occurs
in the conversion of the free-radical betaine (1) into the trione (3) is a
novel type of N to p-aromatic rearrangement which
presumably entails dissociation followed by recombination and oxidation.
Studies on Intramolecular Alkylation, XI. An Adventitious Synthesis of a 1,4-Ethanopentalene Derivative from a Norbornenone-Derived Diazomethyl Ketone
Authors: Mander LN , Wilshire C
Published: September 2010

The C2-epimeric mixture of
2-chloro-7-formylbicyclo[2,2,1]hept-5-ene-2-carbonitriles (5) was homologated
by simple synthetic steps to the norbornenone-derived acids (12) and (13). The
diazomethyl ketone derived from (12), on treatment with BF3,Et2O
in nitromethane, gave (lα(,3aβ,4α(,6aβ)-3,3a,4,6a-tetrahydro-1,4-ethanopentalene-2(1H),8-dione (20). Structure (20)
was deduced from cleavage by sodium methoxide to a symmetrical methyl ester
derived from bicyclo-[3,2,1]oct-6-en-3-one. The structure of the reported
product dione (8) from the acetic acid treatment of diazoketone (7) has been
revised to (21).
Pyrimidine N-Oxides. II. The Synthesis of Some Amino- and Imino-pyrimidine N-Oxides and Related Compounds
Authors: Cowden WB , Jacobsen NW
Published: September 2010

Substituent effects on the
peroxy acid oxidation of some pyrimidine-2,4,6-triamines are reported together
with the synthesis of new N'-methylpyrimidine
N-oxides and a pyrimidine N,N'-dioxide.
The Crystal Structure of Tetraisothiocyanato-tetrakis(trimethylphosphine oxide)uranium(IV)
Authors: Rickard CEF , Woollard DC
Published: September 2010

The structure of the title
compound has been determined by single-crystal X-ray crystallography. The
crystals are orthorhombic, a 12�122(1),
b 12�545(2), c 22�128(3) �, space group Pccn.
The structure was refined to a final residual of 0�040,1565 structure
amplitudes being used. The molecules are eight-coordinate, the coordination
polyhedron being an almost regular square antiprism, with the thiocyanate
groups bonded through nitrogen.
Acetolysis of endo-5-Methyltricyclo-[2,2,1,02,6]hept-exo-3-yl and endo-5-Methyltricyclo[2,2,1,02,6]hept-endo-3-yl p-Bromobenzenesulfonates
Authors: Dell A , Johnson BL
Published: September 2010

Acetolyses of the title
compounds (4b) and (5b) at 25�7� proceed with steady first-order kinetics and
with comparable rate constants. Some isomerization of (5b) to (4b) occurred
during acetolysis of (5b). The products derived from acetolysis of each p-bromobenzenesulfonate were comparable
and included endo-5-methyltricycl0[2,2,1,02,6]hept-exo-3-yl acetate (4c), endo-5-methyltricyclo- [2,2,1,02,6]hept-endo-3-yl acetate (5c), endo-3-methylbicyclo[2,2,1]hept-5-en-exo-2-yl acetate (6) and anti-7-methylbicyclo[2,2,1]hept-5-en-exo-2-yl acetate (7). These results are
rationalized in terms of a reaction mechanism involving isomerization of the endo to the exo intimate ion pair, (10) to (ll), as well as a capturable
intermediate carbocation which is common to the acetolysis of both p-bromo- benzenesulfonates.
Synthesis and 13C N.M.R. Studies of Some Polycyclic Hydrocarbons with Trimethyltin at the Bridgehead
Authors: Della EW , Patney HK
Published: September 2010

The synthesis of
(adamantan-1-yl)trimethylstannane (1),
(bicyclo[2,2,2]oct-1-yl)trimethylstannane (2),
(bicyclo[2,2,1]hept-1-yl)trimethylstannane (3), (cubanyl)trimethylstannane(4) and tricyco[[4,1,1,02,7]- hept-1-yl)trimethylstannane (5) is described and the carbon-13
nuclear magnetic resonance spectra of these compounds are reported. In
particular, it is found that the coupling constant of the directly bonded tin
bridgehead carbon atoms is not greatly dependent on the degree of s character
of the carbon exocyclic bonding orbital and that vicinal coupling between tin
and carbon is observed to fit a Karplus equation. A
linear relationship occurs between 1J(117,119Sn,13CMe)
and 2J(117,119Sn,13HMe).
A Spectroscopic Investigation of Swainsonine: An α-Mannosidase Inhibitor Isolated from Swainsona canescens
Authors: Colegate SM , Dorling PR , Huxtable CR
Published: September 2010

A potent inhibitor of α-mannosidase was isolated from Swainsona canescens. The inhibitor was
shown to be an indolizidinetriol by spectroscopic
techniques and the relative stereochemistry was defined as 8aβ-indolizidine-lα,2α,8β-triol.
Metal Template Reactions. XIII. Synthesis of Macrocyclic Complexes of Ligands Containing Extensive Chromophoric Systems
Authors: Black DSC , Vanderzalm CHB , Wong LCH
Published: September 2010

The preparation of a wide
range of nickel(II), cobalt(II) and copper(II) complexes (5)-(8) of macrocyclic
ligands derived from the diamino dialdehydes (1)-(4) and various substituted
1,2-diamino arenes is recorded. Several free macrocyclic ligands (12), (13) are
also reported.
Oxidation of Copper Sulfides in Aqueous Ammonia. III. Kinetic Characteristics
Authors: Filmer AO , Parker AJ , Clare BW , Wadley LGB
Published: September 2010

The kinetics of oxidation
with oxygen of chalcocite, Cu2S, to CuS in buffered aqueous ammonia
at pH 10.5 at 30� can be modeled approximately by a shrinking core of Cu2S
within a thickening shell of CuxS (x ≥ 1). The Cu2S
core offers partial cathodic protection to the CuxS and diffusion of
Cu+ through CuxS controls the rate of reaction. The kinetics of oxidation
of covellite, CuS, to Cu2+, sulfur and sulfate ions in the same
solvent can be modeled by a shrinking core of CuS surrounded by a shrinking
sphere of CuyS (y < 1) which is much less effectively protected
cathodically by the CuS core. Oxidation of CuS is subject to mixed chemical and
diffusion control. Rates of oxidation of NiS and of CuS, in the presence and
absence of tetrachloroethene and ammonium sulfate, show that, whether sulfur is
a major oxidation product or not, the presence of sulfur has very little, if
any, influence on the rate or mechanism of oxidation. This is contrary to
current ideas on metal sulfide oxidation.
A Pulse Radiolysis Study of the Reaction of the Sulfate Radical Ion in Aqueous Solutions of Styrene
Authors: McAskill NA , Sangster DF
Published: September 2010

The ultraviolet absorption
spectra of the transient species formed during the pulse radiolysis of styrene
and peroxydisulfate (S2O82)solutions
showed that a benzyl-type radical was formed from styrene and the SO4-
radical. The effect of adding Cl- was also
studied. These results are in conflict with the claim1 that a phenylethyl radical was formed from SO4-'
via the styrene cation radical. That study was made on acetonitrile solutions
of styrene, S2O82-, CuCl2 and LiCl and the present results suggest that up to 70% of the
SO4-' radicals may have been converted into Cl2-1
radical which then reacted with styrene.
Purine Analogues as Amplifiers of Phleomycin. VI. The Synthesis and Metabolism of Some Benzothiazole, Benzoxazole and s-Triazolopyrimidine Amplifiers
Authors: Brown DJ , Iwai Y
Published: September 2010

The metabolisms of four 14C-tagged
amplifiers of phleomycin are followed in mice. 2-(Benzothiazol-
2'-ylthio)acetamide (1c) gives mainly the corresponding acid (1e) in the urine;
2-(benzoxazol-2'- ylthio)acetamide (1d) likewise
gives the acid (1f); N-methyl-2-(s-triazolo[4,3-a]pyrimidin-
3'-ylthio)propionamide (2b) gives unchanged material (c. 20%) plus not the
corresponding acid (2c), but its [1,5-a] isomer (3c) in 60% yield; and 2-(5',7'-diethyl-s-triazolo[4,3-
a]pyrimidin-3'-ylthio)-acetamide (2i) proves much more stable by giving mainly
unchanged material (>60%). Minor metabolites are formed in each case. ��� Syntheses and N.M.R. spectra of the above
substrates and related derivatives are reported as well as their activities as
amplifiers of phleomycin against in vitro cultures of Escherichia coli.
A New Polyhalogenated Monoterpene from the Red Alga Plocamium angustum
Authors: Dunlop RW , Murphy PT , Wells RJ
Published: September 2010

A new acyclic monoterpene,
(E)-8-bromo-3,7-dichloro-2,6-dimethylocta-1,5-diene (4), has been isolated as
the major monoterpene component of the red alga Plocamium angustum. A second
component was the previously described cross-conjugated dienone (5).
Cleavage of Ethers to Aldehydes (and Alcohols)
Authors: Pojer PM
Published: September 2010

A general method for the
oxidative cleavage of ethers to aldehydes is reported. It involves the
treatment of the ether with 1-chlorobenzotriazole and the subsequent
hydrolysis of the product.
The nature of iron in Akaganéite (β-FeOOH)
Authors: Childs CW , Goodman BA , Paterson E , Woodhams FWD
Published: September 2010

The Mossbauer
spectra of a size range of synthetic akaganeite
(β-FeOOH) samples containing chloride, and one
sample containing fluoride, in the structural tunnels, have been obtained over
4-295 K. At 295 K the spectra consist of overlapping paramagnetic doublets
which indicate the presence of at least two sites for iron. Typical parameters
for a spectrum of chloride-containing β-FeOOH fitted
to two doublets are: (i) δ (relative to iron
metal) 0.372 mm s-1, Δ 0.55 mm s-1, Г 0.27mm s-1;
(ii) δ 0.375 mm s-1, Δ 0.94mm s-1, Г 0.33
mm s-1, with peak area ratios (i) : (II)
of 60 : 40 for lath-shaped particles and 53 : 47 for spindle-shaped particles.
At 77 K the spectra consist of overlapping magnetic hyperfine components which
indicate the presence of at least three sites for iron, a three-component model
giving internal magnetic fields of about 470 kOe, 460
kOe, and 435 kOe. The spectra
of fluoride-containing β-FeOOH are very similar
to those for chloride-containing β- FeOOH. The
results are explained in terms of two types of octahedra
within the lattice, FeO3(OH)3 and FeO2(OH)4, the extra proton in the second
type balancing the charge on halide ions within the tunnels. Secondary effects
may arise from the interaction of the halide ions with adjacent octahedra. The
effects of modifying the surfaces of β-FeOOH
particles (heating, phosphate sorption) are consistent with modification of the
outer surfaces of the particles only, and it is not necessary to invoke the
presence of large internal pores, of the order of 30Ǻ by 30Ǻ, as has
been suggested by some earlier workers.
Synthesis and characterization of some alkoxide derivatives of nickel(II)
Authors: Baranwal BP , Mehrotra RC
Published: September 2010

A number of alkoxides and chloride alkoxides
of nickel(II) of the types Ni(OR)2, Ni(OR)Cl and
Ni(OR)Cl,ROH have been synthesized from the reactions
of anhydrous nickel(II) chloride with lithium or sodium alkoxides
in appropriate molar ratios. These derivatives have been characterized by
element analysis, infrared, electronic reflectance and electron spin resonance
spectra in addition to magnetic susceptibility measurements. Alcohol
interchange reactions in these alkoxide derivatives
have been studied in detail.
Pyrolysis of aryl azides. V. Characterization of phenylazo, benzoyl and formyl as neighbouring groups
Authors: Dickson NJ , Dyall LK
Published: September 2010

The enhancements of
thermolysis rate of azidobenzene produced by ortho phenylazo, benzoyl and substituents
are 21180, 70.0 and 22.8 at 393.2 K (decalin solutions). The same ortho
substituents produce much smaller enhancements (169, 8.56 and 10.7 respectively)
in the pyrolysis rate of 1-azido-2,4-dibromobenzene.
These results are interpreted as steric effects on an electro-cyclic
thermolysis mechanism, and are not consistent with the alternative
pathway of intramolecular 1,3-dipolar addition which
continues to be advocated by Hall and Dolan.
Crystal structure of Bis(N,N-diethyldithiocarbamato)(isothiocyanato)iron(III)
Authors: Raston CL , Sly WG , White AH
Published: September 2010

The crystal structure of
the title compound [Fe(NCS)(S2CNEt2)2] has
been determined by single-crystal X-ray diffraction methods at 295(1) K and
refined to a residual of 0.054 for 998 'observed' reflections. Crystals are
orthorhombic, P212121, with a 18.70(2), b
15.43(2), c 6.667(6)Ǻ, Z 4. The iron atom of the complex molecule
[Fe(NCS)(S2CNEt2)2] is five- coordinated,
being bonded by four sulfur atoms [Fe-S, 2.257-2.300(5) Ǻ] and the
nitrogen atom of the thiocyanate [Fe-N, 1.91(2)Ǻ].
The thermal decompositions of carbamates. IV. The reactions of isopropyl N,N-dimethylcarbamate and t-butyl N,N-dimethylcarbamate
Authors: Daly NJ , Ziolkowski F
Published: September 2010

The thermal decompositions
of isopropyl N,N-dimethylcarbamate and t- butyl N,N-dimethylcarbamate are shown to occur over the temperature
range 485-602 K through the reactions Me2NCO2Pri
→ Me2NH+CO2+MeCH=CH2
Me2NCO2But
→ Me2NH+CO2+Me2C=CH2
which are described as
first-order unimolecular processes for which the rate equations are
isopropyl k = 1013.04exp(-181209/8.314T)
s-1 �t-butyl k = 1012.87exp(-157904/8.314T) s-1
For both carbamates these
rate equations describe the rates of formation of the amine and the appropriate
alkene but apparently overestimate the rate of carbon dioxide formation. The
discrepancy in the carbon dioxide data is explained in terms of the formation
of an amine-carbon dioxide adduct during the condensation stage of the
analyses. The adduct is described as an ammonium carbamate which undergoes
hydrolysis in solution to free the original amine. The existence of
transesterification in the gas phase is ruled out.
13C and some 15N N.M.R. spectra of heteroaromatic molecules containing bridgehead nitrogen atoms
Authors: Jones AJ , Hanisch P , Heffernan ML , Irvine GM
Published: September 2010

The carbon-13 and (in part)
nitrogen-15 chemical shifts of 1,2,3- triazaindolizine
and seven three ringed analogues of indolizine have been analysed and enable
deductions to be made concerning the extent that the free pair of electrons on
the bridgehead nitrogen atom contributes to the delocalized electronic
structures. Analogies between these molecules and indolizine are noted in that
all the systems possess a high degree of aromaticity.
Additivity relationships for nitrogen and methyl substitution are compared with
those previously reported for other heteroaromatic
molecules.
Comparison of previously published 100-MHz
and the present-work 270-MHz proton n.m.r. results enabled 13C
spectral assignments to be confirmed by selective 1H irradiation
experiments, since coupling constant analyses did not provide unambiguous
assignments in all cases. One-, two-, three- and four-bond 13C-1H
coupling constants are reported for most carbon atoms where first-order
spectral analysis was possible. Several examples of non-first-order behaviour
are presented and attempts to reconcile the occurrence of this behaviour are
outlined.
The reaction of aniline with 5-Nitro-2-furaldehyde. A model for non-enzymic browning reactions
Authors: Rio MDd , Ojeda ODd , Urquia M , Scarabino C , Yunes RA
Published: September 2010

The condensation between
5-nitro-2-furaldehyde and aniline, a model for food browning reactions, yields
the corresponding Schiff base, 5-nitro- 2-furfurylideneaniline, cleanly. The
corresponding reaction with 2- furaldehyde itself
yields, in contrast, a mixture of products. Since the equilibrium constant for
formation of the Schiff base from 5-nitro- 2-furaldehyde and aniline, 177 dm3
mol-1, is not large enough to drive the reaction to completion at
moderate concentrations of aniline, phenylhydrazine
was employed to trap the Schiff base as it was formed: that is, the reaction
with aniline was studied by examining aniline-catalysed phenylhydrazone
formation.
The chemistry of pyrrolic compounds. XLII. The synthesis of some diacetyldeuteroporphyrins as intermediates in the preparation of the isomeric protoporphyrins: a comparative spectroscopic study of the diacetyldeuteroporphyrins
Authors: Clezy PS , Fookes CJR
Published: September 2010

A range of isomeric diacetyldeuteroporphyrins has been synthesized by the
oxidative cyclization of appropriately substituted bilenes-b, and the
electronic and n.m.r. spectra of these porphyrins have been studied. As a
result it has been shown that the relative position of the two acetyl groups
influences the absorption pattern of the visible spectrum more precisely than
was previously appreciated. In consequence, it is possible to recognize the
1,4, 2,3 and 2,4 relative distribution of the acetyl groups by an examination
of the electronic spectrum. In addition, it is clear that the acetyl groups
present in this series of porphyrins affect the chemical shift of all the
methine protons and not only the one which is directly adjacent to the carbonyl
function.
Synthesis of L-Kynurenine peptides conducted without masking the side-chain amino group
Authors: Stewart FHC
Published: September 2010

Various free L-kynurenine
peptides, including an analogue of the opiate agonist leucine-enkephalin, have been
synthesized by using the Nα-t- butyloxycarbonyl
derivative of L-kynurenine as a key precursor. By selecting appropriate mild
conventional coupling procedures it was possible to carry out the synthetic
operations without having to mask the side-chain amino group in any way, but
intramolecular acylation with formation of a seven-membered lactam could be
demonstrated under more vigorous conditions.
A study of chemical reactions in molten sodium-potassium hydrogen sulfate eutectic. III. The reactions of anions
Authors: Meehan BJ , Tariq SA
Published: September 2010

The reactions of 11
inorganic anions added as their sodium or potassium salts to molten sodium-potassium
hydrogen sulfate eutectic were studied and their stoichiometries elucidated. It
was found that Na2CO3, NaNO2, KNO3,
Na2SO3 and Na2S2O3
reacted with the melt to form water and CO2, NO+NO2, NO2+O2,
SO2, S6+SO2 respectively. NaCl,
KBr produced HCl and HBr while KI reaction products consisted of I2,
SO2 and H2O; K2CrO4 and K2Cr2O7
were converted into H2CrO4 and H2Cr2O7
respectively. These acids decomposed to H2O, O2 and Cr2O3
which reacted further with the melt to produce H2O and Cr2(SO4)2,H2O.
K2S2O8 was found to decompose thermally to O2
and K2S2O7 without reacting with the melt.
Polymerization reactions of acrylonitrile on zeolite surfaces
Authors: Petfield AT , Cooney RP
Published: September 2010

Infrared and mass spectral
analyses are reported of the surface species generated when the adsorption
complexes zeolite+acrylonitrile are heated. The evidence
presented indicates that H2O competes favourably for zeolitic
adsorption sites with acrylonitrile. Infrared spectra suggest that a C2
π-bonding interaction may be important in the adsorption of acrylonitrile.
Heating adsorbed acrylonitrile appears to generate polyacrylonitrile products
which may include a cyclic dimer. Extended heating results in the possible
formation of conjugated nitrile species, polyenes and even more extensively carbonized products.
An X-ray structural examination of an intermediate from the cleavage of a vic-diol by iodine(I) acetate
Authors: Beckingsale PG , Waters JM , Waters TN
Published: September 2010

The crystal structure of a
compound isolated after reaction of iodine(1) acetate with cis-cyclohexane-1,2-diol
has been determined by direct methods. It is identified as 2,2'-(butane-1,4-diyl)bis(hexahydro-1,3-benzodioxole).
Crystals are orthorhombic, a 8.625(2), b 7.589(1), c 26.187(5) Ǻ, space
group Pbca, Z 4. Least- squares refinement brought R
to 0.046.
The reaction of β-hydroxy acids with aldehydes
Authors: Fujita T , Watanabe S , Suga K , Isobe T , Miura T
Published: September 2010

β-Hydroxy acids react
with various aldehydes in the presence of acidic materials to give spiro
lactones in good yields. For example, 2-isopropyl-5-methyl-1,3-dioxaspiro[5,5]undecan-4-one
was obtained in 90% yield from the reaction of 2-(1'-hydroxycyclohexyl)propionic acid and isobutyraldehyde.
The reactivity of the tris(oxalato)chromate(III) anion in reversed micellar systems
Authors: O'Conner CJ , Ramage RE
Published: September 2010

The reactivity of the tris(oxalato)chromate(III) anion
has been followed in benzene solutions of dodecylammonium
propionate or octylammonium tetradecanoate containing solubilized water at 298
K. The reaction rate against detergent concentration profiles are complex.
Cobalt(II), nickel(II) and copper(II) complexes of some 2'-hydroxychalcones
Authors: Palaniandavar M , Natarajan C
Published: September 2010

Metal(II) bis-chelates of
the type ML2 [M = CoII, NiII, CuII;
L = 2'- hydroxy-5'-X-chalcone where X = H, CH3, Cl]
have been prepared and studied. Structures have been assessed by the
measurement of magnetic moments, ligand field and infrared spectra and thermal
properties. These chelates possess low-spin trans-square-planar configuration
and show resistance to adduct formation in contrast to metal(II) chelates of
β-diketones, salicylaldehyde,
o-hydroxyaryl ketones and esters and o-hydroxy-crotonophenones, which have high-spin octahedral
configuration. Extensive conjugation lowers the energy of the π3*
orbital which enters into a very strong dπ-π3*
interaction leading to spin-pairing. ��� Infrared spectra indicate that the carbonyl
group is perturbed only slightly by coordination to metal. A change in metal
ion affects v(C=O), v(M-O) and other vibrations and the order of stability,
namely, Co ≈ Ni < Cu, inferred from these vibrations is as expected
for the low-spin square configuration of the chelates. Introduction of substituents
(5'-X) alters only v(M-O)
significantly and the order of stability, namely, Cl
> CH3 > H, derived from v(M-O) is consistent with Taft's resonance
polar parameters of the substituents. All these observations are explained by
the electron sink property of the phenyl group.
Cyclopropylidene insertion reactions : 2-methoxy-1,2-dimethylbicyclo[1, 1, 0]butane
Authors: Hamon DPG , Trenerry VC
Published: September 2010

The syntheses of 1,1-dibromo-2-isopropyl-2-methoxy-3,3-
dimethylcyclopropane (12), 1,1-dibromo-2-methoxy-2,3,3- trimethylcyclopropane
(11), 1,1-dibromo-2-isopropyl-2- methoxycyclopropane (21), 1,1-dibromo-2-methoxy-3,3-
dimethylcyclopropane (29) and 1,1-dichloro-2-methoxy-3,3- dimethylcyclopropane (30)
are described. The compounds (12), (21) and (29) give rise to alkoxy allenes on treatment with
methyllithium in ether. The major product of the reaction of methyllithium with
the dibromide (11) is 2-methoxy-1,2-dimethylbicyclo[1,1,0]butane (26). This is
the first example of this class of compound. Treatment of the compound (30)
with methyllithium in the presence of hexamethylphosphoramide
gave the homologous allene, 2-methoxy-4- methylpenta-2,3-diene
(25).
The gas-liquid transition for 12-6 argon: a grand ensemble Monte Carlo calculation
Authors: Lane JE , Spurling TH
Published: September 2010

New grand canonical
ensemble Monte Carlo calculations of the gas-liquid transition for a Lennard-Jones 12-6 fluid confirm the validity of the
previous calculation by Adams.
Synthetic plant growth regulators. V. The synthesis and crystal structure of a hybrid gibberellin-helminthosporic acid
Authors: Turner JV , Anderson BF , Mander LN
Published: September 2010

(3aRS,4RS,6RS,8aSR)-5-Methyleneoctahydro-4H-3a,6-methanoazulene-4-carboxylic
acid (7) has been synthesized and a detailed comparison made between its
molecular structure and that of gibberellic acid (4). Indane-5-carboxylic acid
(8) was converted by an alternating sequence of reduction and isomerization
into the hydrindene acid (11). The diazomethyl ketone derived from (11) was
transformed to cyclopropyl ketone (12) which was reduced by Li/NH3
with stereochemical inversion at the β-carbon to give a 1:3 mixture of
ketones (13) and (14) respectively. Ketone (14) was then converted into the
title acid (7) by a standard procedure. ��� Molecules of (7) crystallize in space group
P2/c with a 7.782(1), b 11.055(1), c 14.559(3) Ǻ, β 116.05(1)°. The
structure was solved by direct methods and refined by full-matrix least squares
to a final R value of 0.053.
A new dibenzofuran and diphenyl ether from the lichen Gymnoderma melacarpum
Authors: Chester DO , Elix JA
Published: September 2010

The dibenzofuran melacarpic
acid [1-heptyl-3-hydroxy-7-methoxy-9- methyldibenzofuran-2-carboxylic acid],
the diphenyl ether congrayanic acid
[2-(3'-carboxy-2'-heptyl-4',6'-dihydroxyphenoxy)-4-methoxy-6- methylbenzoic
acid] and the depsidones grayanic acid and fumarprotocetraric
acid have been shown to be constituents of the Australian lichen Gymnoderma melacarpum (Wils.) Yoshim.
Group 6 metal carbonyl complexes of tridentate olefinic tertiary diphosphines. Crystal and molecular structure of {(E)-1,3-Bis[2-(diphenylphosphino)phenyl]-propene}tricarbonyltungsten(0),W(CO)3 {(E)-o-Ph2PC6H4CH=CHC6H4PPh2-o}
Authors: Bennett MA , Corlett S , Robertson GB , Steffen WL
Published: September 2010

The ligands (L) (E)-2,2'-bis(diphenylphosphino)stilbene, (E)-o-Ph2PC6H4CH=CHC6H4PPh2-o
(bdps), (E)-1,3-bis[2-(diphenylphosphino)phenyl]propene, (E)-o-Ph2PC6H4CH=CHCH2C6H4PPh2-o
(bdpp), and (E)-1,3-bis[2-(diphenylphosphino)phenyl]but-1-ene,( E)-o-Ph2PC6H4CH=CHCHMeC6-
H4PPh2-o (bdpb), form complexes of general formula M(CO)3L (M = Cr, Mo, W). N.m.r. (1H,
13C and 31P) and i.r. data indicate that the metal atoms are octahedrally coordinated by mutually
trans phosphorus atoms and the double bond of the olefinic tertiary diphosphines and by meridionally
disposed carbonyl groups. Conformational isomers of the complexes of bdpb can be detected
by n.m.r, spectroscopy, but there is no evidence for similar conformers in the corresponding complexes
of bdps and bdpp. The crystal and molecular structure of W(CO)3(bdpp),0.5CH2C12 has been determined
by single-crystal X-ray diffraction analysis. The crystals are triclinic, space group PI, with
a 10.1 13(Z), b 13.820(2), c 14.512(3) A, α 76.24(1), β 88.08(1), γ 76.31(1)°. The structure, solved
by the heavy-atom method and refined to a conventional R of 0.049 for 8418 diffractometer data,
confirms the conclusions drawn from spectroscopic studies. The olefinic double bond of bdpp is
attached symmetrically to the metal atom [W-C(olefin) 2.403(8), 2.387(9) Ǻ] and is roughly parallel
to the P-W-P axis. The C=C bond length of 1.359(11) Ǻ is only slightly longer than that expected
for the free ligand and is indicative of relatively weak metal-olefin back-bonding. Other important
bond lengths are: W-P 2.450(2), 2.462(2) Ǻ and W-C(C0) 2.020(7), 2.024(7) Ǻ (CO trans to CO)
and 1.971(7) Ǻ (CO trans to olefin).
Ligand substitution at five-coordinate copper(II) centres by cyanate, chloride and bromide ions
Authors: Coates JH , Collins PR , Lincoln SF
Published: September 2010

The substitution of the
aqua[tris{2-(dimethylamino)ethyl}amine]copper(II)
ion by cyanate, chloride and bromide ions has been
studied in aqueous solution by static and stopped-flow spectrophoto-metric
techniques. This process is unusually slow for ligand substitution at a
copper(II) centre and appears to proceed through an interchange mechanism in
which the copper(II)-aqua ligand bond makes a major contribution to the
transition state energetics.
Rate constants for the gaseous reactions OH + C2H4 and OH + OH
Authors: Farquharson GK , Smith RH
Published: September 2010

The rate of disappearance
of hydroxyl radicals (generated by H+NO2 → OH+NO) along a
discharge flow tube both with and without ethene present was measured by resonance
fluorescence. Stoichiometry was simultaneously measured with a mass
spectrometer, the leak into which was located downstream of the resonance
fluorescence cell. After allowing for loss of hydroxyl by known homogeneous
reactions and for wall loss (when applicable) it was found that for OH+C2H4
the low pressure limiting third-order rate constant kter was (3.1 �
0.5)x 10-29 cm6 s-1 at approximately 298 K. In
addition an estimate for the second- order rate constant for OH+OH was
obtained, namely (1.7 � 0.2) × 10-12 cm3 s-1.
These results are discussed in relation to previous measurements.
Cyclopentadienyl-ruthenium and -osmium chemistry. X. Reactions of vinylidene complexes with alcohols and water: syntheses of alkoxy(alkyl)carbene, acyl and alkyl complexes
Authors: Bruce MI , Swincer AG
Published: September 2010

Simple ligand-exchange
reactions between Ru(C2Ph)(PPh3)2(η-C5H5)
and L afford Ru(C2Ph)(L)-(PPh3)(η-C5H5)
[L = CO, CNBut, PMe3 or P(OMe)3]. These complexes, and other
σ-acetylides, Ru(C2R)(PPh3)2(η-C5H5)
(R = Me or CO2Me), react with HPF6,OEt2 to
give the corresponding vinylidene complexes {Ru(C=CHPh)(L)(PPh3)(η-C5H5)]PF6
or [Ru(C=CHR)(PPh3)2(η- C5H5)}PF6;
which in turn react more or less readily with MeOH to
give {Ru[C(OMe)CH2Ph](L)(PPh3)(η-C5H5)]PF6
or {Ru[C(OMe)CH2R](PPh3)2(η-C5H5)}PF6;
the complexes {Ru[C(OR)CH2Ph](CO)(PPh3)-(η-C5H5)}PF6
(R = Et or Pri) and {Ru[C(OMe)CH2Ph](dppe)(η-C5H5)}PF6
were formed in analogous reactions. Water reacts with [Ru(C=CHPh)(L)(PPh3)(η-C5H5)]PF6
to give RuX(CO)(PPh3)(η-C5H5)
(L = PPh3, X = CH2Ph; L = CO, X = COCH2Ph),
the former being formed by a spontaneous alkyl migration reaction.
Orbital interactions. X. The effect of remote substituents on the electrophilic bromination of a series of stereoisomeric 9-substitutedhexahydro-l,4-methanobiphenylenes
Authors: Paddon-Row MN , Lap BV , Patney HK , Warrener RN
Published: September 2010

A series of stereoisomeric
9-substituted hexahydro-1,4- methanobiphenylenes, (4)-(10),were synthesized and
their products and relative rates of bromination (Br2/AcOH)
determined. Bromination occurred exclusively at the 6-position to give
compounds (16) and (17). The syn-methyl ether (5) was
found to be at least 3 × 105 times more reactive than the
corresponding ketone (7) in the exo-fused series. With the aid of INDO MO SCF
calculations it was concluded that: (a) the enhanced reactivity of syn-methyl ether (5) compared with the parent hydrocarbon
(4) is a consequence of orbital interactions through space; (b) of the
2000-fold diminished reactivity of ketone (7) compared with the parent
hydrocarbon (4), a factor of 40 may be attributed to inductive and orbital
interactions through bond effects; the residual factor of 50 is due largely to
(repulsive) electrostatic field effects operating between the carbonyl carbon
atom and the developing positive charge on the aromatic ring during
electrophilic attack.
Studies on intramolecular alkylation. XII. Stereochemical aspects of the preparation of β,γ-unsaturated aldehydes from the [2,3]-sigmatropic rearrangement of ammonium ylides
Authors: Mander LN , Turner JV
Published: September 2010

The [2,3]-sigmatropic
rearrangement of a series of acetonitrile-derived allylic ammonium ylides [RCH2N+
(C4H8)-CHCN; R = 4'-t- butylcyclohexylidenemethyl
(3), 4'-t-butylcyclohex-1-enyl (10), 5'-t- butyl-2'-methylcyclohex-1-enyl (14),
4'-t-butyl-2'-methylcyclohex-1- enyl (20)], followed
by acid-catalysed hydrolysis in each case, furnished an excellent yield of a
diastereomeric pair of β,γ-olefinic
aldehydes [(5)/(6), (12)/(13), (15)/(16) and (21)/(22)]. With cyclohexylidene
ylide (4) addition of the carbanion to the more exposed (equatorial vector)
face is strongly preferred. In the cyclohexenyl examples there is a clear
stereoelectronic requirement in opposition to steric forces which leads mainly
to axial carbon-carbon bond formation.
The chemistry of lauren-l-ene. II. Remote functionalization reactions of the laurenan-2-ols and the 1bH-laurenan-2-ols
Authors: Nath NK , Weavers RT
Published: September 2010

The course of the iodine/lead
tetraacetate oxidation of the four alcohols laurenan-2β-ol(2),
laurenan-2α-ol (3), 1βH-laurenan-2β-ol (4) and
1βH-laurenan-2α-ol (5) is described. Structural assignments have been
made with the aid of 13C n.m.r. after ether ring opening and
conversion into derivatives of lauren-1-ene (1). Where possible, the results of
remote functionalization have been used to infer the preferred molecular
conformation.
Purine studies. XXIII. Conformational aspects of N-(6-amino-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-y1)formamides and related N-benzyl derivatives
Authors: Fenn MD , Lister JH
Published: September 2010

The occurrence of 'Z' and
'E' conformers in 5-formamidouracil derivatives has been investigated by 1H
n.m.r. and the effect of the nature and size of the substituents on the isomer
ratio studied. Also considered was the relative steric competition between the
benzyl and uracil moieties. As it is known that cyclic substituents with groups
located ortho to the formamido group can induce rotation of the plane of the
latter group into an orthogonal position to the plane of the ring, evidence for
a corresponding effect in the case of the 6- aminouracil
derivatives was sought. Similar but more restricted studies have been made with
related 5-thioureidouracil analogues.
Complex formation of nickel(II) ions with citric acid in aqueous solution: a potentiometric and spectroscopic study
Authors: Hedwig GR , Liddle JR , Reeves RD
Published: September 2010

From a potentiometric
and visible spectrophotometric study of the
nickel(II)-citric acid (H3L) system in the pH range 3-6, four
complexes, NiL-, NiHL,
NiH2L+ and NiL24-, have been
characterized. Stability constants for the formation of these complexes have
been determined at 25°C in 0.1 mol dm-3 KCl.
The results suggest that the hydroxy group of citric acid is coordinated in the
nickel-citrate complexes.
Torsional angles and substituent effects in phenyl-substituted azoles by carbon-13 N.M.R. chemical shifts
Authors: Fong CW
Published: September 2010

The torsional
angles in 31 N-phenyl-substituted azole derivatives have been estimated by use
of the 13C substituent chemical shifts of the meta and para carbon
atoms. Steric interaction between the C 5 substituent on the azole rings and
the ortho hydrogen atoms of the benzene ring is the major cause of
non-planarity in these compounds. The azole rings undergo structural
deformation with varying substituents on the azole ring. The inductive effect
of a number of azole and azolium rings is discussed.
Constituents of Eupomatia species. VI. The structures of eupodienone-1, -2 and -3
Authors: Bowden BF , Read RW , Taylor WC
Published: September 2010

Eupodienone-1, from the
bark of Eupomatia laurina, has been shown by spectroscopic and degradative studies
to have the novel neolignan structure (2), (7R,8S,9R)-9-acetoxy-2,3,3',4,5'-pentamethoxy-7,8-
dimethyl-6,7,8,9-tetrahydrospiro[5H-benzocycloheptene-5,1'-cyclohexa-
2',5'-dien]-4'-one. Eupodienone-2 is the corresponding 9-hydroxy derivative (3)
and eupodienone-3, the 9-benzoyloxy derivative (4). The substance EL3 is the
9-ethoxy derivative (5), an artefact.
A 13C N.M.R. investigation of 1-aryl-2-methylcyclo-pentyl and -hexyl cations
Authors: Coxon JM , Schuyt HA , Steel PJ
Published: September 2010

The 13C n.m.r,
spectra of series of 1-aryl-2-methylcyclo-pentyl and -hexyl cations are reported
and the relationship of these data to 2- arylbicyclo[2,2,1]hept-2-yl cations is
discussed.
The effect of isotopic substitution on self-diffusion in methanol under pressure
Authors: Hurle RL , Woolf LA
Published: September 2010

Data have been obtained for
self-diffusion in methanol to approximately 250 MPa
pressure and methan(D)ol to
about 304 MPa at 283, 298 and 313 K and at
atmospheric pressure at 328 K. The average value of the ratio of the diffusion
coefficients at atmospheric pressure is given by
������������� DR=D(CH3OH)/D(CH3OD)=1.09�0.03
At each temperature there
is an increase in DR with pressure to a maximum at 250 MPa which is c. 6 % greater than the value at atmospheric
pressure. The value of DR at atmospheric pressure is much greater
than would be expected from the classical (smooth hard spheres) behaviour.
Analysis of these values of DR in conjunction with moments of inertia data
suggests that the major influence on diffusion is rotation of the methanol
molecule about the principal axis.
Synthetic plant growth regulators. VI. The partial synthesis of optically active (4β,15α)-18-Norkaurene-15-carboxylic acids from (4β)-18-norkauren-3-one by means of a pyrrolidinium ylide rearrangement
Authors: Cossey AL , Mander LN , Turner JV
Published: September 2010

(4β)-18-Norkaur-16-en-3-one
(4a) was alternatively acetalized (ethanediol/Dowex resin) or deoxygenated
(tosylhydrazine/sodium borohydride); allylic bromination (N-bromosuccinimide)
of the products, followed by alkylation of pyrrolidine gave primary allylic
amines which were quaternized with chloroacetonitrile. Potassium
t-butoxide-induced [2,3]-sigmatropic rearrangement, followed by acidic
hydrolysis and Jones oxidation, gave respectively
(4β,15α)-3-oxo-18-norkaur-16-ene-15- carboxylic acid (10a) and (4β,15α)-18-norkaur-16-ene-15-carboxylic
acid. Reductions of (4a) and (10a) gave, with K-Selectride, axial (3β)- alcohols
and, with sodium borohydride, mainly equatorial (3α)-alcohols. Details of
a related conversion of (+)-phyllocladene into (15α)- phyllocladene-15-carboxylic
acid are also recorded.
New metabolites from the brown alga Caulocystis cephalornithos
Authors: Kazlauskas R , Mulder J , Murphy PT , Wells RJ
Published: September 2010

The antiinflammatory
principle of the brown alga Caulocystis cephalornithos has been shown to be 6-tridecylsalicylic
acid. Four other metabolites, 3-tridecylphenol, pentadec-1-ene,
(E)-heptadec-3-en- 2-one and 8-hydroxy-3-undecyl-1H-2-benzopyran-1-one were
also isolated from the dichloromethane extract of the freeze-dried alga.
Stability constants for metal complexation by isomers of mimosine and related compounds
Authors: Stunzi H , Harris LN , Perrin DD , Teitei T
Published: September 2010

Stability constants for the
Mg2+, Ca2+, Cu2+ and Zn2+ complexes
of two isomers (2) and (3) of the defleecing agent mimosine (1) have been
sought from potentiometric titrations in aqueous
solution, 0.15 M KNO3, at 37°. For the interpretation of the
results, complex formation of the simpler ligands 3-hydroxypyridin-4(1H)-one
(4), its 2-oxo isomer (5) and
DL-α-amino-β-(6-oxo-1,6-dihydropyridin-2-yl)propanoic acid (6) was
studied. The results with ligand (2) are very similar to those with mimosine,
for which a computer blood-plasma model indicates metal chelation under
physiological conditions. Ligand (3) is a much weaker complexing agent.
Crystal structures of (Z)-O-β-D-xylopyranosyl(1 → 6)-→-D-glucopyranosyloxy-NNO-azoxymethane (Macrozamin) and 5-O-methyl-myo-inositol (Sequoyitol)
Authors: Cannon JR , Raston CL , Toia RF , White AH
Published: September 2010

Crystal structures of
(Z)-O-β-D-xylopyranosyl(1→6)-β-D- glucopyranosyloxy-NNO-azoxymethane
(macrozamin) (1) and 5-O-methy-myo-inositol
(sequoyitol) (4)-both of which are constituents of Macrozamia riedlei (Fisch. ex Gaud.) C. A. Gardn.-have
been determined by X-ray diffraction. Diffractometer data at 295 K were refined
by least-squares techniques to residuals of 0.050 (1537 'observed' reflections)
for macrozamin and 0.060 (1052) for sequoyitol. Crystals of macrozamin are
monoclinic, P2I, a 8.315(3), b 10.410(4), c 10.423(5) Ǻ, β
106.42(3)°, Z 2. Crystals of sequoyitol are triclinic, Pī,
a 4.780(5), b 6.502(6), c 14.668(10) Ǻ, α 96.43(7), β 94.20(8),
γ 109.31(8)°, Z 2.
Crystal structures of nitron and its non-stoichiometric hydrochloride
Authors: Cannon JR , Raston CL , White AH
Published: September 2010

The crystal structures of
the hemi-ethanolate of nitron, C20H16N4(C2H6O)0.5,
and of a non-stoichiometric hydrochloride of nitron, C20H16N4(HCl)1.7(H2O)3.3, have been
determined by X-ray diffraction from diffractometer data at 295 K and refined
by block diagonal least squares to residuals of 0.069 (2049 'observed'
reflections) and 0.055 (1915), respectively. Crystals of the hemi-ethanolate of
nitron are monoclinic P21/n, a 12.697(6), b 15.821(5), c 19.064(6)
Ǻ, β 108.79(3)°, Z 8. Crystals of the non-stoichiometric
hydrochloride of nitron are also monoclinic C2/c, a 25.41(1), b 5.968(6), c
29.40(2) Ǻ, β 103.53(5)°, Z 8. Despite some unusual features in their
molecular geometry, these structures are consistent with the mesoionic
character of nitron.
N-Acetyl-2,3,5,6-tetrachloro-p-benzoquinone imine
Authors: Fernando RC , Calder IC
Published: September 2010

N-Acetyl-2,3,5,6-tetrachloro-p-benzoquinone
imine is best prepared by direct chlorination of N-(4-hydroxyphenyl)acetamide.
The tetrachloro quinone imine is a stable compound with a high oxidation-reduction
potential and may be a useful addition to the range of conventional high potential
quinones. Some typical oxidation reactions are described as well as some
reactions with nucleophilic reagents.
Acidity of hyperconcentrated electrolyte solutions. Hammett acidity function measurements for aqueous ZnCl2, + LiCl solutions
Authors: Crane SG , Easteal AJ
Published: September 2010

The Hammett acidity
function has been evaluated by means of spectrophotometric measurements with
thymol blue indicator for (1-x)(ZnCl2,RH2O)+x(LiCl,RH2O)
pseudobinary mixtures where R is 4 and 6. The pseudobinary mixtures have well
defined minimum acidity near the composition (x = 0.67) which corresponds to
the tetrachlorozincate ion stoichiometry. The acidity data for these mixtures
support the conclusion that the properties of mixtures with R ≤ 6 are
dominated by formation of tetrachlorozincate anions.
Vapour pressure and ideality of the equimolar mixture of H2O and D2O
Authors: Jancso G , Jakli G
Published: September 2010

The pressure differences
between H2O and the equimolar H2O-D2O
mixture were measured between 5 and 90°C and the experimental data can be
represented by the equation
����������������� In(pH2O/pmix)
= 0.076624-88.161/T+25972/T2
where T is the absolute temperature.
For comparison the vapour-pressure differences between pure H2O and
D2O were also determined. The results show that the H2O-HDO-D2O
liquid mixture does not deviate from the ideal behaviour within the limits of
the experimental data. The present investigation supports the earlier
conclusion that the law of the geometric mean for the vapour-pressure isotope
effect in the series H2O, HDO and D2O is not obeyed.
Cadmium-111, cadmium-113 and mercury-199 N.M.R. studies of tetrahalometallate complexes
Authors: Colton R , Dakternieks D
Published: September 2010

The cadmium-111 and
cadmium-113 n.m.r. spectra of the complexes (Nbu4)2CdX4
(X = Cl, Br, I) have been observed in dichloromethane
solution. Cadmium n.m.r. spectra were observed for mixtures of pairs of these
anions, and at low temperatures the mixed halo complexes were observed in the
statistical distribution. An equimolar mixture of all three halo anions gave
all 15 possible mixed halo species in the statistical distribution at -80°C. ��� Mercury-199 n.m.r. spectra of (NBu4)2HgX4
were observed. Mixed halide complexes were difficult to observe because of low
solubility at low temperatures, but they were detected in mixtures containing
HgBr42-.