bluuebunny/crossref_metadata_2025 huggingface dataset:
The reaction of isocyanates with bisulphite salts
Authors: Guise GB , Jackson MB , Maclaren JA
Published: September 2010

Aliphatic isocyanates react
rapidly and quantitatively with aqueous bi-

sulphite solutions to form stable water-soluble adducts which
are salts of N-alkyl-carbamyl sulphonio acids. Phenyl
isocyanate gives lower yields of the corresponding
adduct which is less stable in water. The rate of reaction of n-butyl isocyanate with bisulphite
increases with increasing pH and is proportional to [OH-]over the pH range from
5 to 8. The rate of decomposition of the butyl isocyanate-bisulphite
adduct increases with increasing temperature and pH. A plot of the logarithm of
the initial first-order rate constant for the decomposition of the adduct
against pH is linear over the pH range from 2 to 7 and has a slope of 0.57 � 0.05.
Water-insoluble polymers
with aliphatic isocyanate groups do not form bisulphite adducts under the conditions which are suitable
for simple isocyanates. However, the addition of water-soluble organic solvents
such as dioxan and the lower alcohols enables the
preparation of water-soluble bisulphite adducts which
are indefinitely stable at room temperature and low pH. The relative quantity
of the organic solvent must be kept within
specific limits which depend on the nature of the prepolymer,
the solids content of the final product, and the nature of the organic co-solvent.
Monocyclopentadieny1titanium(III) compounds. III. Complexes of oxygencontaining ligands
Authors: Coutts RSP , Martin RL , Wailes PC
Published: September 2010

Complexes of the type cpTiX2,nL
[where cp = π-cyclopentadienyl; X = Cl or Br; n
= 1 when L = 1,2-dimethoxyethane (dme); n = 2 when L
= ethanol (EtOH), or methanol (MeOH)]
have been prepared. Various physical properties, including magnetism and
electronic spectra, have been measured and interpreted on the basis of
six-coordinate titanium(III) atoms. The magnetic moments of all complexes
approximate to the spin-only value. ��� Reactions with dioxan did not result in the
formation of stoichiometric complexes, while β-diketones caused rupture of
the cp-Ti bonds as well as the halide-titanium bonds giving known tris-β- diketonates of titanium(III).
Activities of silver chloride in molten chlorides
Authors: Jindal HL
Published: September 2010

The activities of silver
chloride in molten MgCl2-KCl (32.5 : 67.5 mole %) and in molten MgCl2-NaCl-KCl
(50 : 30 : 20 mole %) as solvent at 475�C have been determined by measuring the
e.m.f. of the galvanic cell:

����������������� Ag | AgCl
(in melt) || melt | Cl2 (graphite)

as a function of silver
chloride concentration in the solution. The extent of deviations from ideal
behaviour in these solvents has been compared with those observed in other
mixed chloride solvents and the results are interpreted on the basis of the
interactions of the various solvent cations.
Preparation of substituted benzofurans. Pyridine-induced solvent shifts in their N.M.R. spectra
Authors: Yuste F , Walls F
Published: September 2010

A number of benzofurans and
related benzofuranol derivatives have been prepared and fully identified by
spectral criteria. The structures of these substances have been established by
means of pyridine-induced solvent shifts in the p.m.r.
spectra.
Thermodynamics of the dimerization of copper(II) Phthalocyanine-4,4',4'',4'''-tetrasulphonic acid
Authors: Blagrove RJ , Gruen LC
Published: September 2010

The relevant thermodynamic
parameters for the dimerization of copper(II) phthalocyanine-4,4?,4?,4??-tetrasulphonic
acid ion have been measured in a variety of aqueous solvents. It has been found
that both the enthalpy and entropy of dissociation are increased in the
presence of compounds which enhance the structure of water. Conversely, both of
these parameters are decreased by structure-breaking compounds. The results are
discussed in terms of the bonding forces responsible for dimerization.
Carbonyl nitrosyl halide complexes of molybdenum and tungsten
Authors: Barraclough CG , Bowden JA , Colton R , Commons CJ
Published: September 2010

The monomeric carbonyl
nitrosyl halide complexes M(CO)4(NO)X (M = Mo, W; X = Cl, Br, I),
except Mo(CO)4(NO)Cl, have been prepared by the reaction of nitrosyl
ion upon M(CO)5X- salts. ��� The infrared and mass spectra of these
compounds are reported and discussed.
A 1H and 14N magnetic resonance study of the exchange of acetonitrile on nickel(II)
Authors: Lincoln SF , West RJ
Published: September 2010

A 1H and 14N n.m.r. study of the exchange reaction Ni(MeCN)62+ ↔ MeCN
in MeCN solvent is reported. From the rate law: R = 6k298[Ni(MeCN)62+] the
values k298 = (3.6 ± 0.6 ) × 103 and (2.0 ± 0.3) × 103 s-1; ΔH‡ = 59.6 ± 8.8 and
68.4 ± 2.0 kJ rnol-1; and ΔS‡ = 23 ± 16.7Jmol-1 K-1 and 50 ± 8.0 J mol-1 K-1
are derived from 1H and 14N data respectively. The apparent discrepancies between
the two kinetic data sets, and the modes of relaxation of the 1H and 14N nuclei, are
discussed.
Stabilization of an adjacent carbocation centre by cycloalkyl groups. The uniqueness of cyclopropyl
Authors: Sorensen TS , Miller IJ , Ranganayakulu K
Published: September 2010

In the ability of
cycloalkyl groups to stabilize an adjacent carbocation centre, a cyclopropyl
group is uniquely effective. Cyclobutyl, cyclopentyl, and cyclohexyl groups are
about as effective as paraffinic substituents.
Conformations of some N-sulphinylanilines
Authors: Bonham JS , Cheng CL , Le FFvre RJW , Ritchie GLD
Published: September 2010

Experimental dipole moments
and molar Kerr constants are reported for six N-sulphinylanilines
as solutes in carbon tetrachloride at 25�C. Analysis of the data yields
information concerning the preferred conformations of these molecules.
Use of N-bromosuccinimide in the synthesis of heterocyclic systems
Authors: Dhaka KS , Chadha VK , Pujari HK
Published: September 2010

N-Bromosuccinimide has been
used in the synthesis of a series of imidazothiazoles.
It is both quicker and more convenient to use than other reagents.
Electrical conductivity of fused lead bromide + potassium bromide mixtures
Authors: Jeffery EA , Mole T
Published: September 2010

Bridge-terminal exchange of
methyl groups in trimethylaluminium dimer and the exchange of methyl groups between
the dimer and trimethylgallium or dimethylzinc are all interpreted as
proceeding by initial rate-determining dissociation of the trimethyl-aluminium
dimer to liquid-caged monomer pair. Most exchange occurs before the monomers of
the pair become separated. An alternative mechanism in which exchange follows
separation is rejected. ��� The choice of mechanism is based on (a) p.m.r. kinetics of exchange between trimethylgallium and
trimethylaluminium in cyclopentane; (b) p.m.r.
kinetics of exchange between dimethylzinc and trimethylaluminium in
cyclopentane; and (c) estimates of the rate of recombination of
trimethylaluminium monomer.
Hydroboration of chromenes, flav-2-enes, flavylium salts, and flavones
Authors: Clark-Lewis JW , McGarry EJ
Published: September 2010

By hydroboration and
oxidation chrom-2-ene gave chroman-3-ol, and chrom-3-ene gave chroman-4-ol with
only a minor quantity of chroman-3- ol. Hydroboration
of coumarin to chroman-3-ol therefore proceeds through chrom-2-ene instead of
through chrom-3-ene as previously proposed. Successive hydroboration and
oxidation of 4?-methoxyflav-2- ene and of 4?-methoxyflavylium
chloride each gave a mixture of 3-(2-
hydroxyphenyl)-1-(4-methoxyphenyl)propan-2-ol, 3-(2-hydroxyphenyl)-1- (4- methoxyphenyl)propan-1-ol,
and 4?-methoxyflavan (formed by cyclization of the diarylpropan-1-ol), The same
three products were obtained by hydroboration and oxidation of 4?-methoxyflavone,
in this case accompanied by 2,3-trans-4?-methoxy-flavan-3-ol, 2,4-trans-4?- methoxyflavan-4-ol,
and 2,3-trans-4?-methoxyflavan-3,4-trans-diol. N.m.r. data are presented on the
compounds obtained.
Polynuclear acetylacetonatodimethoxyiron(III)
Authors: Kokot E , Mockler GM , Sefton GL
Published: September 2010

The complex [Fe(acac)(OMe)2]
was prepared. The temperature dependence of the magnetic susceptibility
indicates that the complex is an antiferromagnet and that it may be binuclear.
Substituent effects on the sterochemistry of reaction of (Z)-stilbenes with brommine
Authors: Hartshorn MP , Opie MCA , Vaughan J
Published: September 2010

Electron-donating
substituents favour cis-addition of bromine to 4,4?- substituted (2)-stilbenes;
trans-addition is favoured by electron- withdrawing substituents.
SCLC theory for a Gaussian trap distribution
Authors: Bonham J
Published: September 2010

A simplified one-carrier
space charge limited conduction theory has been developed for a Gaussian trap
distribution in. an insulator. It is shown that the distribution behaves much
like a discrete trap level at low applied fields, although the current has a
temperature dependent activation energy. At higher fields the current-voltage
relation becomes superquadratic, but this does not account for the behaviour
normally attributed to an exponential trap distribution.
Non-empirical molecular orbital calculations based on Slater-type orbitals. A restricted use of Gaussian expansions
Authors: Brown RD , Burden FR , Williams GR
Published: September 2010

An ab-initio SCFMO
technique of balanced computational speed and precision is described for use
with Slater-type orbitals as basis. All of the more significant integrals over
STO'S are evaluated with full arithmetic accuracy but the ?non-NDDO?
two-electron integrals are evaluated less precisely by using small Gaussian
expansions. ��� The overall numerical accuracy achieved in
calculations of total energy and  are illustrated for a number of
small molecules using both 2G and 3G expansions. The performance, especially
with respect to energy calculations, is clearly superior to that of analogous
methods that have recently been described.
Fluorescence decay of aromatic vapours. II. Single vibronic level lifetimes of the isolated naphthalene molecule
Authors: Knight AEW , Selinger BK , Ross IG
Published: September 2010

The lifetimes of single
vibronic levels of naphthalene-h8 and ?d8 have been
studied under collision-free conditions in the vapour. The lifetime of the
vibration less 1B3u state of naphthalene-d8
was found to be 485�5 ns. At sufficiently high resolution of the exciting light
the fluorescence decay is exponential. The mean fluorescence lifetime of the
prepared state decreases with increasing vibrational energy content but not as
a smooth function of energy. The ratio of lifetimes for the 0� and 8(b18)1
states is explicable entirely in terms of the differing radiative pathways for
electronic relaxation. The quantum yields for these states of naphthalene-h8
are estimated to be of the order of 0.45 and 0.63 for the 0� and 8(b18)1
state respectively. ��� The lifetimes of comparable states show a
normal deuterium isotope effect; for higher energies where the errors are
larger the evidence is less certain.
Octahedral cobalt(III) complexes of the chloropentanimine type. XXX. The thallium(III)-induced aquation of some cis-Halogeno(amine)bis(ethylenediamine)cobalt(III) cations in aqueous solution
Authors: Chan SC , Chan SF
Published: September 2010

The second-order rate
constants for the thallium(III)-induced aquation of cis-[Co(en)2(RNH2)Cl]2+ cations, where R is H, Me, Et, Prn, and Pri,
have been measured in aqueous solution over a range of temperatures, and the
activation parameters calculated. The kinetic results are discussed in terms of
a rapid pre-equilibrium formation of an activated complex Co-Cl-Tl, followed by a simple rate-determining aquation in
which TlCl2+ acts as the leaving group, although the alternative
possibility of a rate-determining attack by Tl3+ cannot be excluded.
In the case of R = H, the investigations have been extended to the
corresponding bromo cation which reacts some 50 times faster than its chloro
analogue.
The polarography of some substituted azobenzenes in acetonitrile. II. Identification of reduction products
Authors: Boto KG , Thomas FG
Published: September 2010

The reduction products of
azobenzene and 4-nitroazobenzene in acetonitrile were investigated by
polarography and ultraviolet-visible spectrophotometry after generation by
controlled potential electrolysis. The results obtained indicate that
azobenzene is reduced in two steps to give firstly the monoanion and secondly
the monoprotonated form of the dianion, whereas 4-nitroazobenzene gives the
monoanion and the dianion, respectively, as the products of the two
one-electron reduction steps. The azobenzene monoanion undergoes a very slow
disproportionation (k = 8.2 dm3 mol-1 min-1)
to produce azobenzene and the monoprotonated dianion in equimolar amounts. The
second reduction products of both compounds are stable in the absence of
oxygen.
The thermal decompositions of casbamates. III. Ethyl N,N-dimethylcarbamate and the effect of N-substitution upon the β-elimination
Authors: Daly NJ , Heweston GM , Ziolkowski F
Published: September 2010

Ethyl N,N-dimethylcarbamate
thermolyses to, N,N-dimethylamine, carbon dioxide, and ethylene in a
homogeneous molecular reaction. First-order rate constants are described in s-1
units by the equation

������������������������� log k =
12.10-(44340�400)/θ

where θ = 4.576T. The
pattern of substituent effects for N-substitution and values of ΔS?
for several N-substituted carbamates show that ring closure through the
carbonyl oxygen is favoured over the alternative cyclization involving the
nitrogen atom.
Halogenated terpenoids. VII. Carvone tetrabromides and carvone tetrachlorides
Authors: Carman RM , Venzke BN
Published: September 2010

The structural formulae of
the α- and β-carvone tetrabromides and the α- and β-carvone
pentabromides are deduced. The reaction of sodium iodide upon these compounds
has been investigated. Two new crystalline carvone tetrachlorides have been
synthesized and their structural relationship with carvone tetrabromide
determined.
The reaction of formaldehyde arylhydrazones with excess formaldehyde and the acetylation of arylhydrazines
Authors: Johns SR , Lamberton JA , Nelson ER
Published: September 2010

A detailed examination of
the reaction of excess formaldehyde with formaldehyde phenylhydrazone and
formaldehyde 4-bromophenylhydrazone has shown that the products are the
respective 3,6-endo-methylene-1,4- diarylhexahydro-s-tetrazines [(4) and (II)],
the symmetrical 2?- oxapropano compounds [(8) and
(10)] and the unsymmetrical 2?-oxapropano compounds [(7) and (9)]. These
products are analogous to those obtained from formaldehyde
4-nitrophenylhydrazone but are formed in markedly different proportions. Analogous
products cannot be obtained from formaldehyde 2,4-dinitro-phenylhydrazone which
affords 5-(2,4- dinitrophenylamino)dihydro-1,3,5-dioxazine
(12). ��� A study has also been made of the
conditions under which formaldehyde phenyl-hydrazone undergoes oxidative
dimerization to glyoxal bisphenylhydrazone, and it has been shown that under
appropriate conditions 4-anilino-2-phenyl-2,3,4,5-tetrahydro-1,2,4- triazine
(13) can be conveniently prepared. ��� The acetylation of arylhydrazines has been
studied and the products characterized by their N.M.R. spectra.
Selective bromination of substituted acetophenones with dioxan dibromide
Authors: Pasaribu SJ , Williams LR
Published: September 2010

Dioxan dibromide has been
used to selectively brominate the side chain of acetophenones.
The decomposition of Exo-D2-triazolines derived from Bicyclo[2,2,1]heptenes: Stereospecific formation of exo-aziridines
Authors: Halton B , Woolhouse AD
Published: September 2010

Pyrolysis of Δ2-triazolines
derived from substituted bicycloheptenes gives only aziridines. N.m.r. data for
reactants and products are discussed.
Azole aldehyde condensations
Authors: Browne EJ
Published: September 2010

Some aldol
type condensations of benzimidazole-2-carbaldehyde and 5- aryl-1,2,4-triazole-3-carbaldehydes
are described. The dimeric structure of the solid aldehydes has been confirmed
by mass spectrometry of their trimethylsilyl ethers.
The reactions of hydrazines with trans-Dichlorobis(ethylenediamine)cobalt(III)chloride, and the isolation and kinetic studies of a Chlorobis(ethylenediamine)methylhydrazinecobalt(III) isomer
Authors: Chan SC , Lee CK
Published: September 2010

The reactions of hydrazine,
methylhydrazine, and 1,1-dimethylhydrazine with trans-dichlorobis(ethylenediamine)cobalt(III)
chloride in concentrated and dilute solutions are studied. In concentrated
solution, there is a reduction by hydrazine to form the insoluble polymeric [CoII(N2H4)2Cl2]n,
a substitution by methylhydrazine to form chlorobis(ethylenediamine)methylhydrazinecobalt(III) chloride, and a
disproportionation with 1,1-dimethylhydrazine to form
tris(ethylenediamine)cobalt(III) chloride. In dilute solution, the reaction
observed is a hydroxide substitution by hydrolysis of 1,1- dimethylhydrazine,
a reduction to soluble cobalt(II)-ethylenediamine species with hydrazine, and a
mixture of both processes for methylhydrazine. The chlorobis(ethylenediamine)methylhydrazinecobalt-(III) chloride obtained is a new
complex, and is assigned a cis configuration on the basis of spectroscopic
observations. The kinetics of its intramolecular electron-transfer, as well as
its acid and base hydrolyses are also studied.
Isotope studies of the isomerization of olefins homogeneously catalysed by palladium, platinum, and rhodium complexes
Authors: Cruikshank BI , Davies NR
Published: September 2010

No entry of deuterium into
olefin could be detected as a result of isomerization of allylbenzene in the
presence of palladium(II) catalysts in CH3CO2D or CH3OD.
The deuterium isotope effect on the rate of isomerization was found to be high
in the case of CH3CO2D, but slight in the case of CH3OD.
In the case of catalysis by rhodium complexes, entry of deuterium into olefin
occurs in CH3OD but not in CH3CO2D. Isotope
effects parallel those observed with palladium(II). The isomerization of PhCD2CH2CH=CH2
catalysed by palladium(II) results in a near-to-random distribution of
deuterium throughout the side chain. The results are consistent with a hydrido-π-olefin
complex mechanism of isomerization. Differences between catalysis by
palladium(II) and rhodium(III) are discussed in terms of possible differences
in the mechanism of formation of the active catalyst. In the case of palladium
it is concluded that a relatively rapid rate of σ-π interchange and
hence of double bond shift occurs within the equilibrium system of catalyst and
olefin, and that exchange of olefin with the substrate constitutes the slower,
rate-determining step. The behaviour of platinum(II) is generally similar to
that of palladium(II) but is only effective at higher temperatures.
Electron solvation processes in alcohol-hydrocarbon mixtures
Authors: Brown BJ , Barker NT , Sangster DF
Published: September 2010

The solvated electron has
been investigated in mixtures of polar and non-polar liquids (methanol,
ethanol, propanol, and isopropyl alcohol respectively in hexane) by
pulse-radiolysis. The respective yields and transition energies of the electron
in the mixtures do not show the same dielectric dependence as has been
established for pure liquids. The relative number of electrons escaping
geminate recombination increases with an increase in the alcohol concentration
but the mechanisms of optical transition and electron decay remain unchanged.
Infrared spectroscopic studies have shown that electron stabilization is
related to the existence of quasi-stable associated alcohol complexes. For
ethanol, an observed decrease in the solvated free electron yield with an increase
in temperature is in accord with a shift in associative equilibrium.
The metal-metal interaction in binuclear Bis(cyclopentadienyl)titanium(III) halides
Authors: Coutts RSP , Martin RL , Wailes PC
Published: September 2010

Measurements of the
temperature dependence (80-380 K) of the magnetic susceptibility of
polycrystalline bis(η-cyclopentadienyl)titanium(III) halides [(η-Cp)2-
TiX2Ti(η-Cp)2] with X = F, Cl,
Br, and I are reported. Characteristic singlet-triplet behaviour is observed with
the strength of the Ti-Ti d1-d1 interaction increasing in
the sequence F < Cl ≈ I < Br. The
position of I ≈ Cl is unexpected and structural
data will be required to resolve this anomaly.
Reduction of chlorothallium(III) complexes by arsenic(III)
Authors: Sharma PD , Gupta YK
Published: September 2010

The oxidation of
arsenic(III) by thallium(III) in perchloric acid solution is inhibited by
chloride ions. The reactivity of various chlorothallium(III) species is in the
order Tl3+ > TlCl2+ > TlCl2+
> TlCl3 > TlCl4-. The rate decreases by
increasing the hydrogen ion concentration and ionic strength. The redox process
occurs by intermediate formation of a complex of thallium(III) and arsenic(III).
The rate constant for the reaction between Tl3+ and arsenic(III)
calculated from the data of the present investigation compared well with that
of the reaction1 in the absence of chloride ions.
Formation of arylacetic acids, arylacetamides, and aryldihydropyrroles from aromatic aldehydes
Authors: Breen L , Eastwood FW , Ockman T , Rae ID , Redwood AM
Published: September 2010

Furfuraldehyde,
4-hydroxybenzaldehyde, and 4-hydroxy-3-methoxybenzalde- hyde
were converted into 2-furylacetic, 4-hydroxyphenylacetic and 4- hydroxy-3-meth-oxyphenylacetic
acids respectively on reaction with glyoxal bisulphite and cyanide in alkaline
solution. Under the same reaction conditions, 2-hydroxybenzaldehyde yielded 2- hydroxyphenylacetic
acid and 3-(2?-hydroxypheny1)-2H-chromen-2-one. When ammonia was present in the
reaction mixture, furfuraldehyde and 4- hydroxy-benzaldehyde formed
2-furylacetamide and 4- hydroxyphenylacetamide
respectively. Alternatively, in the presence of methylamine, furfuraldehyde
yielded 5-(2?-furyl)-2-imino-1-methyl-2,5- dihydropyrrole-3,4-diol and
benzaldehyde gave the corresponding phenyldihydropyrrolediol.
The chemical shifts of the methoxyl in anisole derivatives
Authors: Ng S
Published: September 2010

The n.m.r. spectra of anisole and 20 methyl-, t-butyl-, adamant-1-yl-, and
chloro-substituted anisoles were obtained in dilute solutions in CCl4, CHCl3, and C6H6.
In the non-aromatic solvents the methoxyl proton resonance shifts upfield with di-o-alkyl
substitution, relative to anisole or o-alkyl substitution. However, this upfield shift is
not observed in the case of di-o-chloro substitution. In benzene the methoxyl resonance
exhibits the aromatic-solvent induced shift, and this shift is larger with ortho than with
di-ortho substitution. Relative to anisole, alkyl substitution at the para or meta position
shifts the methoxyl resonance slightly upfieid in the non-aromatic solvents, but slightly
downfield in benzene. However, chloro substitution at the ortho or the para position
shifts this resonance upfield in benzene. In the mono-o-substituted derivatives, the
methoxyl resonance shows a doublet structure, consistent with spin-spin coupling with
the o-proton (J c. 0.20 Hz).
A spectroscopic study of sulphide, selenide, and telluride complexes of palladium(II) and mercury(II)
Authors: Fergusson JE , Loh KS
Published: September 2010

trans-Square planar
complexes of the type PdX2L2 (X = Cl, Br, I, NO3,
NO2 and L = R2S, Et2Se, Et2Te,
PhRS, PhEtSe) have been prepared and studied using low-frequency i.r., 1H
N.M.R., and u.v.-visible spectroscopic techniques. The i.r. and u.v.-visible
spectral bands have been assigned. The 1H N.M.R. spectra have proved
informative in separating out the different electronic effects transmitted
through both the bonding system as well as through space. Evidence for low
temperature inversion about the pyramidal sulphur atom has been obtained for a
number of complexes. The dimeric, halogen-bridged mercury(II) complexes [HgX2L]2
(X = Cl, Br; L = R2S Et2S, Et2Te and X = I; L
= Et2Se) have been isolated and studied in a similar manner.
Neutral Extractives From Pinus radiata Bark
Authors: Weston R
Published: September 2010

n-Alkanes C13-C34,
isoalkanes C15-C19, waxes, docosanol,
tetracosanol, (24R)-24-ethylcholest-4-en-3-one,
(24R)-24-methylcholest-5-en-3β-ol,
(24R)-24-ethylcholest-5-en-3β-ol
(β-sitosterol), (13S)-labda-8(17),14-
dien-13β-ol(13-epimanool), C(14a)-homo-27-norgammacer-14-ene-3β,21α- diol (serratenediol),
C(14a)-homo-27-norgammacer-14-ene-3β,21β-diol
(21-episerratenediol), 3β-hydroxy-C(14a)-homo-27-norgammacer-14-en-21-
one, and 3β-methoxy-C(14a)-homo-27-norgammacer-14-en-21 one have been
identified in the neutral fraction of the benzene extractives from the bark of Pinus radiata D. Don.
The crystal structure of diethylene tetraxanthogen, the oxidation product of the diethylene dixanthate ion
Authors: Hoskins BF , Hunt MR
Published: September 2010

The structure of the oxidation product of
the diethylene dixanthate
anion, diethylene tetraxanthogen
(Cl12H1606S8), has been determined
by single crystal X-ray diffraction methods. The crystals are tetragonal of
space group Z41/acd with a 15.798(1), c 17.755(1) �, containing eight molecules per unit cell. The
structure was solved using conventional Patterson and Fourier methods and
refined by a full-matrix least-squares method to R 0.055 for the 817
independent statistically significant reflections collected by counter methods.
The crystals are composed of discrete molecules held together by van der Waals forces. Each molecule,
situated about a site of symmetry 222, has the novel 22-membered ring structure
involving disulphide bonds of length 2.035(2) �. The planarity of the dithiocarbonate moiety and the relatively short
carbon-to-oxygen and carbon-to-sulphur bond lengths
correlate with extensive π-electron
delocalization over the group.
Phase equilibria in the system ZnCl2 + KI
Authors: Easteal AJ , O'Rourke PJ
Published: September 2010

Phase equilibria
in the ZnCl2+KI system have been investigated by differential
thermal analysis (DTA), and by examination by X-ray powder diffraction of
solidified melts. The system evidently behaves as a simple binary, and three
congruently melting compounds are formed, viz. 2KI.ZnCl2, 2KI.3ZnCl2
and KI.4ZnC12.

Supercooled mixtures from c. 60-90 mole % ZnCl2
visibly phase separate at temperatures for the most part about 30K below the liquidus temperatures, and the phase separation
temperatures have been determined by DTA. The composition limits of the
metastable immiscibility dome have not been established, but the region of
phase separation extends at least to mixtures containing as little as 53 mole %
ZnCl2. The critical composition is approximately 80 mole % ZnCl2,
and the critical temperature 470 K. Quenching of melts containing 34-100 mole %
ZnCl2, in liquid nitrogen, yields glasses. In the region 34-43 mole
% ZnCl2 the glasses are partly crystallized. Glass transition
temperatures for the wholly glassy mixtures have been evaluated from DTA
traces, with heating rates in the range 0.11-0.25 K s-1. Two glass
transitions have been observed for mixtures of composition 53-75 mole % ZnCl2.
Complexes of vanadium(II) with heterocyclic and aliphatic amines
Authors: Khamar MM , Larkworthy LF , Patel KC , Phillips DJ , Beech G
Published: September 2010

Complexes of vanadium(11)
with a range of heterocyclic and aliphatic amines have been isolated, generally
from ethanolic solution under nitrogen. With pyridine (py) and β- and γ-picolines (β pic and γ pic) complexes of the general formula V(amine)4X2,
in which X = Cl, Br, or I, have been obtained. Their
reflectance spectra are dominated by charge transfer bands, but some d-d
transitions have been assigned. These complexes are magnetically dilute with
magnetic moments near to 3.87 B.M. The only bis(amine) complexes isolated with
these ligands are V(β pic),Br, and V(γ pic)2Br2, and these show considerable
antiferromagnetic interaction because of polymeric structures. The thermal
behaviour of the complexes V(amine)4X2 resembles that of
the corresponding nickel(11) complexes. No definite assignments of V-X
stretching frequencies have been possible. With ethylenediamine
(en), propane-1,2-diamine (α pda),
propane-1,3-diamine (β pda) and diethylenetriamine (dien) the
following magnetically dilute complexes have been isolated : [V(en)3]
X2, [V(αpda)3] X2,
[V(βpda)3] X2 and [V(dien)2] X2. These complexes with
aliphatic chelates have electronic spectra typical of octahedral vanadium(11).
The 8-aminoquinoline (amq) complexes, V(amq)2Cl2,- 2H20, V(amq)2Br2,2H2O and V(amq)3I2,2H20, have more
complicated electronic spectra and are magnetically dilute as are some 1,l0-phenanthroline
and 2,2'-bipyridyl complexes of general type [V(chelate)3] X2,nH2O.
Homogeneous metal catalysed isotope exchange and oxidation of aromatic and aliphatic compounds in aqueous acetic acid containing platinum(IV) halide
Authors: Garnett JL , West JC
Published: September 2010

PtCl62-
reacts with benzene and substituted benzenes in aqueous acetic acid to give
PtCl42-, chlorinated aromatic compound and a smaller
yield of dimer. In deuterated solvent extensive hydrogen isotope exchange
occurs in both substrate and chlorinated product. PtCl42-
is shown to be an active catalyst for both exchange and oxidation reactions.
Chlorobenzene is chlorinated predominantly in the meta and para positions with
approximately equal activity. These data together with results from the effect
of substituents indicate that metal catalysed chlorination is not determined by
electronic factors but by steric considerations, in marked contrast to
electrophilic chlorination. Similarly, PtBr42- is a
catalyst for bromination of benzene when the compound is treated with PtBr62-.
Exchange and chlorination occur via common intermediates and it is proposed
that -complexes between
aromatic and PtCl42- are involved. Analogous
chlorination, with PtCl62-, of cyclohexane and the side
chain of certain alkylbenzenes has also been
observed. The structures of possible intermediates in these latter reactions
are discussed.
The photochemical rearrangement of 5-(1',5'-Dimethylhex-4'-enyl)-6-methoxy-7a-methyl-3H-indazole-4,7(3aH,7aH)-dione, the pyrazoline derivative of O-methylperezone
Authors: Salazar I , Enriquez R , Diaz E , Walls F
Published: September 2010

Irradiation of the
pyrazoline derivative of O-methylperezone
(2) by ultraviolet light yielded the tricyclic compounds (4) and (5), the tetra
substituted compound (3) and the tetracyclic compound (6).
The oxide-solution interface
Authors: Perram JW , Hunter RJ , Wright HJL
Published: September 2010

We extend previous
treatments of the gel model of the oxide-solution interface and solve exactly
the most general soluble case, of such an oxide in the presence of a 1 : 2-2 :
1 electrolyte, for the distribution of charge and potential across the
interface. We calculate values of the surface charge and zeta potential of the
oxides TiO2, Fe2O3, SiO2 and M203
using reasonable values of adsorption potentials and dissociation constants
taken from tables. We find, for the samples of such oxides for which high measured
charges have been reported, that we can account quantitatively for all the data
by characterizing the interface by a gel layer of thickness 20-40�. We infer
that such comprehensive agreement, and the consistency in all cases of the high
charge and low zeta potential with the theory, gives strong support to the view
that a thin surface layer distorted by the penetration of water and all types
of ions is a general feature of the oxide-solution interface.
Donor properties of 2-aminothiazole and 2-acetylaminothiazole towards cobalt(II) halides
Authors: Singh PP , Srivastava AK
Published: September 2010

Molecular addition
complexes of the type CoL2X2 (X = Cl,
Br, I and L = 2-aminothiazole and 2-acetylaminothiazole) have been prepared and
studied by infrared spectra, electronic spectra, magnetic susceptibility and
X-ray powder data. Infrared and electronic spectra suggest coordination through
exocyclic nitrogen in 2-aminothiazole and through carbonyl oxygen in
2-acetylaminothiazole. The complexes have tetrahedral configuration and belong
to the C2" point group. Ligand field parameters Dq, B' and β show more covalency in
2-aminothiazole complexes than in 2-acetylamino-thiazole complexes and suggest
a weak ligand field for both the ligands.
The camphenehydro (methylcamphenilyl) and isobornyl (bornyl) cations. I. Generation of the enantiomeric cations by the π- and σ-routes of solvolysis
Authors: Gream GE , Wege D , Mular M
Published: September 2010

The acetolysis of α-campholenyl
[2-(2',3',3'-trimethylcyclopent-3'-enyl)] p-nitrobenzenesulphonate
proceeds with π-bond participation to give cyclized products (99.7%)
derived from the equilibrating classical camphene hydro and isopropyl cations.
The composition of the product is similar, but not identical, to those formed
by the σ-route from the acetolysis of suitable isopropyl and bornyl
derivatives. When α-campholenyl p-nitrobenzenesulphonate
and the isopropyl derivatives are prepared from (+)-camphor, the two
enantiomers of camphene having high optical purities are formed. A simple
procedure for the preparation of camphene of high optical purity from
isoborneol is described.
The products of pyrolysis of the 2- and 3-dimethylaminomethylindoles at 820°
Authors: Brown RFC , Hooley N , Irvine FN
Published: September 2010

The major products of flash
vacuum pyrolysis of the 2- and 3-dimethylaminomethylindoles at 820�include dimethylaminoacetonitrile, methylaminoacetonitrile,
quinoline, o-vinylbenzonitrile
and

indole; the 2-isomer also forms some benzonitrile.
Electron impact studies. LXXXVI. Ion-molecule reactions of alkyl and aryl cyanides
Authors: Bowie JH , Williams BD
Published: September 2010

Positive ion-molecule
reactions of representative alkyl and aryl cyanides have been studied by ioncyclotron resonance spectroscopy. The major secondary
ion produced from alkyl cyanides is an [MH]+ species. Neutral alkyl
cyanides react preferentially with even-electron ions produced from alkyl
cyanide molecular ions by the general process

+R1 + R2CN
→ R2-C=N+-R1

but the corresponding aryl
cyanides react with both odd- and even-electron ions. The characteristic
reaction of acetonitrile,'s2 viz.

CH2CN+ + CH3CN → C3H4N+
+ HCN

does not occur for higher
homologues, but a mixture of acetonitrile and propionitrile
gives the analogous reaction

CH2CN+ + C2H5CN → C4H6N+
+ HCN
Organophosphorus compounds. XI. Synthesis of some 1,2,3,4,5,6-Hexahydro-1,5-methano-4,1-benzazaphosphocines
Authors: Collins DJ , Rowley LE , Swan JM
Published: September 2010

1-Hydroxy-1,2,3,4-tetrahydrophosphinoline 1-oxide (2a) was converted via the corresponding acid
chloride (2b) into the 1-vinylphosphine oxide (3) which underwent a Michael-like addition with
dimethylamine to give 1-(2'-dimethylaminoethyl)-1,2,3,4-tetrahydrophosphinoline 1-oxide (6). The
successive reduction of (6) with trichlorosilane, and oxidation with sulphur afforded the phosphine
sulphide (7).
The reaction of 1-vinyl-1,2,3,4-tetrahydrophosphinoline 1-oxide (3) with N-bromosuccinimide
followed by treatment with dimethylformamide gave 1-vinyl-1,2-dihydrophosphinoline 1-oxide
which, under mild conditions, underwent Michael-like addition of amines to the vinyl group to
give, for example, 1-(2'-propylaminoethy1)-1,2-dihydrophosphinoline 1-oxide. When heated in a
sealed tube at 140-150° in water for 60 h this amine was converted into 4-propyl-1,2,3,4,5,6-hexa-
hydro-1,5-methano-4,1-benzazaphosphocine 1-oxide. Several related tricyclic compounds including
the corresponding phosphines and phosphine sulphides were synthesized.
Several of the new aminophosphorus compounds were tested for analgesic activity.
Organophosphorus compounds. XII. A new synthesis of phosphindolines and phosphindoles
Authors: Collins DJ , Rowley LE , Swan JM
Published: September 2010

The reaction of
2-phenylethylphosphonous dichloride with zinc chloride at 170� followed by
hydrolysis with concentrated hydrochloric acid, and oxidation, gave 72% of
1-hydroxyphosphindoline 1-oxide. Treatment of the derived phosphinic chloride
with vinyl magnesium bromide at -40� afforded 1-vinylphosphindoline 1-oxide
which underwent addition of dimethylamine to yield 1-(2'-dimethylaminoethyl)phosphindoline
1-oxide. The conversions of 1-chlorophosphindoline 1-oxide into 1-ethyl- and
1-phenyl-phosphindoline 1-oxide are described. Bromination of l-methoxy-
phosphindoline 1-oxide with N-bromosuccinimide followed by dehydrobromination
afforded 1-methoxyphosphindole 1-oxide. 1-(2'-Dimethylaminoethyl)phosphindoline
1-oxide and the corresponding phosphine sulphide were assayed for analgetic
activity.
The Mills-Nixon effect. IV. Base-catalysed cleavage of Trimethylsilyl-veratrol, -1,3-benzodioxole and -1,4-benzodioxan derivatives
Authors: Brocklehurst LJ , Richards KE , Wright GJ
Published: September 2010

The rates of cleavage for
4-trimethylsilyl-veratrol, 5-trimethylsilyl-1,3-benzodioxole and 6-trimethyl-
silyl-1,4-benzodioxan have been measured at 30�C in 1 : 9 water-dimethyl
sulphoxide containing sodium hydroxide. The benzodioxole derivative is more reactive
than the other two substrates; this enhanced reactivity arises from
hybridization changes enforced on the ring junction carbons by the strained
dioxole ring.
The modification of coordinated acetonitrile lability on cobalt(II) induced by the coordination of 2,2-Di(aminomethyl)propan-1-ol
Authors: Lincoln SF
Published: September 2010

A single acetonitrile
exchange process on Co(diap)(MeCN)32+
(where diap is 2,2-di(aminomethyl)-propan-1-ol)
in acetonitrile solution is observed by 14N N.M.R. between 221 and
315.6 K. On the assumption that this process characterizes the two equivalent
acetonitrile sites the following parameters are derived: kex(298 K) = (45 � 3) x 105 s-1, ΔH?
= 3l.0 � 2.5 kJ mol-1, ΔS? = -l4 � 6 J Mol-1 K-1,
where the exchange rate is given by 2kex[Co(diap)(MeCN)32+].
Alternative interpretations are also discussed.
γ-Terpinene nitrosochloride
Authors: Carman RM , Singaram B , Verghese J
Published: September 2010

γ-Terpinene
nitrosochloride has structure (3a). The structure and
conformation of amines derived from this structure are also discussed.
Catalytic deuterium exchange reactions with organics. LXX. The deuteration of alkyl hydrogens in the short-chain alkylbenzenes using homogeneous platinum and heterogeneous platinum and nickel catalysts
Authors: Garnett JL , Kenyon RS
Published: September 2010

The mechanism of deuterium
exchange in the short-chain alkylbenzenes has been
studied using a homogeneous sodium tetrachloroplatinate
catalyst in acetic acid solution. Carbon-14 labelled ethylbenzene
has been synthesized and used to differentiate between previously proposed
mechanisms. When deuteration of the side chain in ethylbenzene occurs, there is no scrambling of the α
and β carbon atoms, thus eliminating the role of a symmetrically
coordinated ethylene group previously proposed. This conclusion is confirmed by
theoretical calculations of the exchange in ethylbenzene.
The ethyl group in ethylbenzene derivatives deuterates with a low multiple character. These results
from the homogeneous platinum system have been compared with corresponding data
using heterogeneous platinum and nickel catalysts. Analogous intermediates are
shown to be capable of existing in both homogeneous and heterogeneous systems,
and are postulated to be general π-complexes for aromatic deuteration and π-allylic
species for alkyl group exchange.
The rates of basic methanolysis of some N-Alkyl-p-nitroacetanilides and 4-(N'-Alkylacetamido)pyridines
Authors: Broxton TJ , Deady LW , Williamson PRA
Published: September 2010

Rate constants for the
basic methanolysis of CH3CONRAr compounds (R=H,Me,Et,Pri;
Ar = p-NO2C6H4,
4-pyridyl), and derived activation parameters are reported. There is a close parallel
between the effects of the nitro and aza groups on
activation energies and entropies foreach R group. The order of
reactivity within the R groups is H < Me > Et > Pri. From a
consideration of the activation parameters it seems likely that the lower
reactivity of the H-compounds is due to the energetically unfavourable breakdown
of strongly hydrogen-bonded structures during methanolysis of these compounds.
Cyclitols. XXXV. Tridentate complexing of some C-methyl- and C-hydroxymethyl-cyclitols with borate ions
Authors: Angyal SJ , Klavins JE , Mills JA
Published: September 2010

Several C-methyl-,
deoxy-C-methyl-, C-hydroxymethyl- and C-methoxymethyl-inositols have been
synthesized. The equilibrium constants for the formation of tridentate borate
esters and the electrophoretic mobilities in borate solution have been
determined. They were found to be in accordance with the values expected from
conformational considerations, except for the C-hydroxymethyl derivatives which
form complexes other than tridentate ones. The structures of the complexes were
determined by n.m.r, spectroscopy.
Insect Moulting Hormones: The Synthesis of Possible Ecdysone Precursors for Metabolic Studies
Authors: Galbraith M , Horn DS , Middleton E
Published: September 2010

The possible biological
precursors of ecdysones, 3β-hydroxy-5β-cholest-7-en-6-one
(2) and 3β,14α-dihydroxy-5β-cholest-7-en-6-one (3), are prepared
from 7-dehydrocholesterol through their 5α-epimers.The corresponding 3α-[3H]
derivatives of high specific activity are prepared in a similar way via
5α-cholest-7-ene-3β,6α-diol[3α-3H] 6-acetate
which is obtained by reducing the corresponding 3-keto derivative with sodium
borotritide.
Studies on intramolecular alkylation. III. The preparation of γ-lactams from podocarpic acid: Models for diterpene alkaloid synthesis
Authors: Balgir BS , Mander LN , Prager RH
Published: September 2010

Several methods for the introduction of a 6β,16 nitrogen
bridge in podocarpane derivatives are described. Attempted intramolecular N-alkylation in the 6α-bromo amide
(9) gave ketol (13) via imino ether (10). Attempted lactam formation from the
6-oxo nitrile (22) or 6-oxo ester (24) gave no useful result, but the
diosphenol(15) gave lactam (16), which was reduced to the target lactam (28).

A further route to (28) via the 6-ene derivative of amide (7) is
also described. The lack of identity between (28) and the γ-lactam formed
from photolysis of O-methylpodocarpoyl
azide indicated that this lactam has the 2β,19 structure (31).
Studies on intramolecular alkylation. IV. The preparation of spirodienones from phenolic diazoketones
Authors: Beames DJ , Mander LN
Published: September 2010

The phenolic diazoketones (7; n
= 3-7) were treated with boron trifluoride etherate in nitromethane. For n = 4, 5 and 6 spirodienones
(8) were isolated as well as the respective benzocycloalkanones
from a concomitant dienone-phenol rearrangement. The formation of (8; n = 4) constitutes the first
demonstrated example of Ar1-4 participation.
The apparent intervention of diimide during a pyridazine synthesis. A re-examination of the reaction between hydrazine and Pyrazine-2,3-dicarboxylic acid derivatives
Authors: Paul DB
Published: September 2010

The reactions of
pyrazine-2,3-dicarboxylic anhydride and dimethyl pyrazine-2,3-dicarboxylate
with hydrazine have been shown to give products resulting from reduction of the
pyrazino rings of theinitially formed pyrazino[2,3-d]pyridazine-5,8(6H,7H)-dione and
3,3'-hydrazodicarbonylbis(pyrazine-2-carboxylic acid). The level of reduction
is substantially diminished when the reactions are carriedout in an inert atmosphere
and it is therefore postulated that the reducing species is diimide.
Reactions of 5-Hydroxy steroids. XIII. The acid-catalysed reactions of Cholestane-4,5-diol 4-acetates and Cholestane-4,5-diol diacetates
Authors: Bathurst ETJ , Coxon JM , Hartshorn MP
Published: September 2010

The reaction of 5α-cholestane-4α,5-diol
4-acetate (lb) with sulphuric acid-acetic
anhydride-acetic acid occurs almost exclusively by loss of the 6α-proton
to give cholest-5-en-4a-yl acetate (3) while dehydration with thionyl chloride-pyridine occurs predominantly (c. 80%) by
loss of the 6β-proton. On reaction with D2SO4-DOAc-Ac2O,
5α-cholestane-4β,5-diol 4-acetate (7) undergoes backbone rearrangement
to give olefins (9),(10) and (11) without incorporation of deuterium and thus
excludes the intermediacy of olefins and cyclopropanes
in the rearrangement process. The effect of substituents on these reactions has
been rationalized by consideration of the initial conformation of the C5 carbonium ion.
Beckmann rearrangement of some steroid α-hydroxy ring B ketoximes: 5-oxo 5,6-seco nitriles
Authors: Ahmad MS , Pillai NK , Chaudhry ZH
Published: September 2010

Five steroid α-hydroxy
ring B ketoximes (1)-(5) were subjected to Beckmann
rearrangement using thionyl chloride and potassium
hydroxide. In each case the products resulted from second-order Beckmann
cleavage. In the case of the dioxime (5), the product obtained was a lactam
nitrile (11).The C3-substituted oximes
(1) and (2) gave, besides the corresponding nitriles (8) and (9), the chloronitrile (6) and the α,β-unsaturated keto nitrile (7). A
probable pathway for the formation of (6) from (1) has been suggested. The mass
spectra of the nitriles (6)-(10) showed a pronounced peak at m/e 110, resulting from the McLafferty rearrangement involving a C8 and/C11-hydrogen
and the C5-keto function. Interestingly, the mass spectrum of (11) did not show
the corresponding peak at m/e 141.
Synthesis of 1,1,2-Triarylalk-1-enes by desulphurization of 3,4-Diaryl-2H-1-benzothiopyrans
Authors: Collins DJ , Hobbs JJ
Published: September 2010

3-Phenyl-1-thiochroman-4-one,
and 7-methoxy-3-phenyl-1-thiochroman-4-one, obtained by cyclization of the
appropriate 2-aryl-3-arylthiopropionic acids, were treated with p-methoxyphenyl- magnesium bromide or
phenylmagnesium bromide, to give, after dehydration, 4-(p-methoxyphenyl)-
3-phenyl-2H-1-benzothiopyran and 7-methoxy-3,4-diphenyl-2H-1-benzothiopyran,
respectively. Desulphurization with Raney
nickel of 7-methoxy-3,4-diphenyl-2H-1-benzothiopyran, or 4-p-methoxyphenyl)-3-phenyl-2H-1-benzothiopyran
gave mainly (E)- or (Z)-1-(p-methoxyphenyl)-1,2- diphenylprop-1-ene, respectively,
with greater stereospecificity in the former reaction. (2)-1-(p- Methoxyphenyl)-1,2-diphenylprop-1-ene
was the major product from the reaction of 4'-methoxy-2-phenylpropiophenone with
phenylmagnesium bromide, followed by dehydration. Some other sulphur-containing
compounds are described.
Infrared and p.m.r. investigations on some complexes of uranyl β-diketonates with methyl-substituted pyridine N-oxides
Authors: Manchanda VK , Subramanian MS
Published: September 2010

Several complexes of uranyl β-diketonates with
pyridine N-oxides having varying
relative degrees of steric hindrance to coordination
(2-methyl-3-methyl-,4-methyl-and 2,6-dimethyl-pyridine N-oxide) were isolated by solvent extraction from the system UO22+-β-diketone-pyridine
N-oxide in benzene. The β-diketones
used were thenoyltrifluoroacetone (tta), benzoyltrifluoroacetone (btfa), acetyl-acetone (acac), benzoylacetone (ba) and dibenzoylmethane (dbm). The
analytical data of these complexes lead to their formulation as UO2(β-diketone)2
pyridine N-oxide. Infrared and
N.M.R. spectra of these complexes are discussed and interpreted in terms of the
substituent constants of the pyridine N-oxide.
The mechanism of lead tetraacetate decarboxylation. II. 2,3,3-Trimethylbutanoic and Adamantane-2-carboxylic acids
Authors: Beckwith ALJ , Cross RT , Gream GE
Published: September 2010

Oxidative decarboxylation of
2,3,3-trimethylbutanoic acid with lead tetraacetate in benzene or acetic acid
affords mainly 3,3-dimethylbut-2-yl acetate; the major product from the cupric
salt catalysed reaction is 3,3-dimethylbut-1-ene. The low yields detected of
rearrangement products provide evidence for the intermediacy of organolead and organocopper
compounds which decompose by SNi
displacement or cyclic cis-elimination.
Other reactions discussed
are oxidative decarboxylation of adamantane-2-carboxylic acid, deamination of 3,3-dimethylbut-2-ylamine, and thermolysis
of bis(2,3,3-trimethylbutanoyl)
peroxide and of t-butyl adamantane-2-percarboxylate. A reinterpretation of
previous results on the oxidative decarboxylation of exo- and endo-nor-
bornane-2-carboxylic acid with lead tetraacetate is presented.