bluuebunny/crossref_metadata_2025 huggingface dataset:
Substituent effects on the basic methanolysis of a series of substituted N-Methyl-p-toluanilides
Authors: Broxton TJ , Duddy NW
Published: September 2010

The rate of basic
methanolysis of a series of substituted N-methyl-p- toluanilides (1) has been
measured at 373 K. A Hammett plot of these results resulted in a straight line
(p 3.1, r 0.998) indicative of reaction by solvent-assisted bond breaking
(mechanism B) throughout the series. The relevance of these results to previous
results for the basic hydrolysis of N-methyl-p-toluanilides (I) and basic
methanolysis of N-methylbenzanilides (2) is discussed.
The composition of reducing sugars in aqueous solution : glyceraldehyde, erythrose, threose
Authors: Angyal SJ , Wheen RG
Published: September 2010

In the syrupy state,
DL-glyceraldehyde, D-erythrose and D-threose consist mainly of mixtures of
dimeric forms. Their aqueous solutions also contain some dimers; glyceraldehyde
is present mainly as the aldehydrol, and the tetroses as mixtures of the furanoses
and the aldehydrol. All the solutions contain some (> 1 %) of the aldehydo
form. The proportion of the monomeric forms has been determined, from the 1H
n.m.r. spectra, at various temperatures.
Complexes of carbohydrates with metal cations. XII. 2,5-Anhydroallitol and 2,5-anhydrogalactitol
Authors: Angyal SJ , Kondo Y
Published: September 2010

The compounds mentioned in
the title were synthesized from 2,5-anhydro- D-glucitol.
2,5-Anhydrogalactitolforms complexes with cations involving the two hydroxyl
groups in the ring and the ring-oxygen atom; 2,5-anhydroallitol does not form
such complexes. The reaction of cis-(2,5- dihydrofuran-2,5-diyl)dimethyl
dibenzoate (5) with iodine and silver acetate was found to be unusual, hydroxylation
occurring from the unhindered side.
Further 13C nuclear magnetic resonance studies of glycals (1,5-anhydro-hex-1-enitols)
Authors: Guthrie RD , Irvine RW
Published: September 2010

Study of 24 derivatives of
D-glucal and D-allal have been used as models to test the findings of Fliszar et
al. with respect to factors affecting the 13C n.m.r.
shifts for saturated and unsaturated carbon atoms.
Synthesis of analogues of GABA. V. trans and cis Isomers of some 4-amino-3-halogenobut-2-enoic acids
Authors: Allan RD , Johnston GAR , Twitchin B
Published: September 2010

Both trans and cis isomers
of 4-amino-3-halogenobut-2-enoic acid have been prepared as potential irreversible
inhibitors of the enzyme GABA- transaminase. trans-Addition of HX to
4-chlorobut-2-ynoic acid and subsequent amination gave the trans isomers (2; X
= Cl, Br, I), while the key step in the synthesis of
the cis isomers (3; X = Cl, Br) was the isomerization
to cis-4-bromo-3-halogenobut-2-enoic acids during allylic bromination. The
stereochemical assignments are supported by 1H and 13C
n.m.r. spectral data. A convenient preparation of cis-4- aminobut-2-enoic acid
by reduction of the bromo derivative is described, as well as the synthesis of
4-phthalimidobut-2-ynoic acid which is suitable for preparing radiolabelled
GABA of high specific activity.
Specific anion effects in the copper(II)-catalysed racemization reaction of the Λ-bis(oxalato)(l,10-phenanthroline)chromate(III) anion
Authors: O'Conner CJ , Odell AL , Dutta-Chaudhuri S , Lan SF , Bailey AAT
Published: September 2010

The kinetics of
racemization of Λ-bis(oxalato)(1,10-phenanthroline)chromate(III) anion in
solutions of CuII salts, at an ionic
strength of 2, fit the expression, rate = (k1+k2[CuIIF])[complex]
where [CuIIF] is the concentration of 'free' copper(II)
ions in solution as calculated from ion pair formation constants for copper(II)
salts. Results in solutions of both constant and nonconstant ionic strength
confirm that the ionic environment of the solvent water is a determining factor
in the magnitude of the catalytic effect. Thus a divalent sulfate medium is
more effective than any of the monovalent perchlorate, nitrate or chloride
salts.
Simplified equation for relaxation of a proton from a rapidly rotating CHXY group and application to nuclear Overhauser measurements
Authors: Pegg DT , Bendall MR , Doddrell DM
Published: September 2010

The usual equation for 1H-1H
dipolar relaxation of a proton from a rapidly rotating CHXY group is
simplified, thus eliminating the dependence upon the varying interaction
distance and the correlation time for internal motion. The final expression
depends only upon two uniquely definable distances and the correlation time for
overall molecular tumbling. The use of this equation for determining
interproton distances by nuclear Overhauser measurements is described.
Electronic effects of halogen-substituted methyl groups
Authors: Fong CW
Published: September 2010

The electronic effects of
the halogen-substituted methyl groups, CHnX3-n, where X
is F, Cl, Br or I, have been examined by 13C
n.m.r, spectroscopy in a series of α-halogen-substituted toluenes. The
substituent chemical shifts of all carbon atoms, as well as the σI and σR0
substituent parameters derived from a dual substituent parameter (DSP)
analysis, are examined in terms of hyperconjugative and π-inductive
substituent effects. Bulky CHnX3-n substituents cause
molecular deformations of the benzene ring, consequently invalidating the
derivation of substituent parameters from a DSP analysis.
The reactions of some 1,1-dialkylhydrazines with unsaturated and bromo aliphatic acids
Authors: Dalton LK , Demerac S , Elmes BC
Published: September 2010

Various 1,1-dialkylhydrazines
are alkylated by propiolic acid or 2- or 3-halopropenoic acids to give
(E)-3-(1,1-dialkylhydrazin-1- io)propenoates. ��� 3-Bromopropionic acid reacts with
N-aminomorpholine to give 1-amino-1-(2-carboxyethyl)-morpholinium bromide (11),
with N- aminopiperidine to give
bis(1-aminopiperidinium) 2-oxo-1-aza-5- azoniaspiro[4,5]decane
tribromide (10), with 1,1-diethylhydrazine to give 1,1-diethyl-3-oxopyrazolidinium
bromide (9) while with 1,1- dimethylhydrazine the 1 :
1 adduct of 3-(1,1-dimethylhydrazin-1- io)propionate
(5a) and 1-(2-carboxyethyl)-1,1-dimethylhydrazinium bromide (8a) is obtained.
The reaction of 1,1-dimethylhydrazine with methyl propiolate, methyl propenoate
and itaconic acid gives (1,1- dimethylpyrazol-1-ium)-3-olate (4),
(1,1-dimethyl-2-pyrazolin-1-ium)-3- olate (1a) and
(1,1-dimethyl-3-oxopyrazolidin-1-io-4-yl)acetate (7) respectively. 1,1-Dimethylhydrazine
reacts with ethyl 3-bromopropionate to give both 1-(2-ethoxycarbonylethyl)-1,1-dimethylhydrazinium
bromide (8b) and (1,1-dimethyl-2-pyrazolin-1-ium)-3-olate (1a) while its
reaction with bromoacetic acid gives the 1 : 1 adduct of (1,1- dimethylhydrazin-1-io)acetate
(5b) and 1-carboxymethyl-1,1- dimethylhydrazinium
bromide (8c).
The solvolysis of 3-cyclooctatetraenylpropyl and 4-cyclooctatetraenylbutyl p-nitrobenzenesulfonates in 2,2,2-trifluoroethanol and 1,1,1,3,3,3-hexafluoropropan-2-ol
Authors: Ferber PH , Gream GE , Wagner RD
Published: September 2010

The advantage of the use,
compared to acetic acid, of 2,2,2- trifluoroethanol and
1,1,1,3,3,3-hexa-fluoropropan-2-ol for promoting π-participation in the
solvolytic reactions of 3-cyclooctatetraenyl- propyl and
4-cyclooctatetraenylbutyl p-nitrobenzenesulfonates is demonstrated. ��� 3-Cyclooctatetraenylpropyl
p-nitrobenzenesulfonate solvolyses in buffered trifluoroethanol and
hexafluoropropan-2-ol with π- participation occurring to the extent of 73
and 99.5 %, respectively. The sole cyclized product is 2,9a-dihydro-1H-cyclopentacyclooctene. 4-Cyclooctatetraenylbutyl
p-nitrobenzenesulfonate solvolyses in buffered trifluoroethanol and
hexafluoropropan-2-ol with π- participation occurring to the extent of 94
and 100%, respectively. In buffered trifluoroethanol, the major cyclized
products are the two isomers of 10a-(2',2',2'-tri-fluoroethoxy)-1,2,3,4,4a,10a-
hexahydrobenzocyclooctene (61.7%) and 1,2,3,10a-tetrahydrobenzo-
cyclooctene (28.9%). The tetraene is almost the
exclusive product (98.8%) in buffered hexafluoro-propan-2-ol. ��� The probable involvement of substituted
homotropylium ions and the role of ion-pairs in the solvolyses are discussed.
Photoconduction in magnesium phthalocyanine thin films
Authors: Ashwell HJ , Bonham JS , Lyons LE
Published: September 2010

This paper describes the
photovoltaic properties of glass/Au/MgPc/Al cells.
High quantum yields were obtained with an applied voltage and moderate yields
at short circuit. No evidence of a Schottky barrier
or p-n junction was observed.
Halogenated terpenoids. XVIII. exo-3-Chlorocamphane (camphene hydrochloride)
Authors: Carman RM , Shaw IM
Published: September 2010

Camphene hydrochloride is
available from the reaction of isoborneol with phosphorus pentachloride.
Light-induced electron-transfer reactions involving the tris(2,2'-bipyridine)ruthenium dication and related complexes. I. The bis(2,2'-bipyridine)(diethyl 2,2'-bipyridine-4,4'-dicarboxylate)ruthenium dication
Authors: Johansen O , Launikonis A , Mau AWH , Sasse WHF
Published: September 2010

Irradiation of the bis(2,2'-bipyridine)(diethyl
2,2'-bipyridine-4,4'- dicarboxylate)ruthenium(II)
dication (2c) in water, in the presence of ethylenediaminetetraacetic
acid, methyl viologen and a platinum catalyst,
produces hydrogen at about one-tenth the rate observed with Ru(bpy)32+. This decrease is ascribed to
electron withdrawal by the ester group in (2c) and to bimolecular quenching of
photo-excited (2c) by water (rate constant 9.3 × 104 1. mol-1
s-1), which follows (in ethanol) Stern-Volmer
kinetics (KSV 9.5 x 10-2 1. mol-1).
Some metal-ion complexes with ligands formed by reactions of amines with aliphatic carbonyl compounds. X. Compounds of some tridentate ligands formed by reaction of copper(II) 2-Aminoethanol and 3-Aminopropan-1-ol complexes with 4-Amino-(and 4-Hydroxy)-4-methylpentan-2-one
Authors: Morgan KR , Curtis NF
Published: September 2010

Compounds of copper(II)
perchlorate with 2-aminoethanol (etol) and 3-
aminopropan-1-ol (prol) react with
4-amino-4-methylpropan-2-one (amp), and with 4-hydroxy-4-methylpropan-2-one (hmp), to form compounds of stoichiometry [Cu(L)] ClO4,
where (L) is a tridentate amine imine olato ligand from amp, or a hydroxy imine
olato ligand from hmp. The etol
condensation products have 'normal' magnetic susceptibilities, while the prol condensation products show antiferromagnetic
spin-coupling. The prol/amp product is diamagnetic at
300 K (-J > 700 cm-1) and the prol/hmp
product has a J of -186 cm-1, based on magnetic susceptibility
measurements over 100-300 K. Preparations of some related nitrate, thiocyanate
and tetrachlorozincate compounds are reported. Possible structures for the
compounds are discussed.
Methyleneketenes and methylenecarbenes. XV. A new synthesis of ruscodibenzofuran
Authors: Brown RFC , Jones CM
Published: September 2010

Ruscodibenzofuran (2-acetyl-6,9-dimethyldibenzofuran-3-ol)
has been synthesized by condensation of
2,4,7-trimethylbenzofuran-3-carbaldehyde with Meldrum's acid, flash vacuum
pyrolysis of the condensation product (8), and overall C-acetylation of the
resulting 6,9-dimethylbenzofuran- 3-ol.
Crystal structure of the acetic acid solvate of the molybdenum(II) acetate/sodium acetate double salt
Authors: Kepert DL , Skelton BW , White AH
Published: September 2010

The crystal structure of
the title compound, Mo2(O2CCH3)4,Na+
- O2CCH3,HO2CCH3, has
been determined by single crystal X-ray diffraction at 295(1) K and refined by
least squares to a residual of 0.040 for 1529 'observed' reflections. Crystals
are monoclinic, space group I2/c, a 8.251(5), b 18.468(9), c 13.674(6) Ǻ,
β 100.25(4)°, Z 4. The compound is shown to have the above stoichiometry,
containing the usual binuclear molybdenum(II) acetate cluster together with
pairs of hydrogen-bonded acetic acid/acetate units.
Diffusion measurements in aqueous L-ascorbic acid solutions
Authors: Shamim M , Baki SMA
Published: September 2010

Diffusion coefficients in
aqueous 0.05-1.0 M L-ascorbic acid solutions have been measured at 298.15 K by
using a modified version of the Stokes diaphragm cell. The diffusion
coefficient of un-ionized ascorbic acid molecule at zero concentration has been
found to be 1.055 × 10-9 m2 s-1. The diffusion
coefficient of an isolated ascorbate ion, C6H7O6-,
is about 23 % lower than the molecular form; this indicates, as expected, that
ions strongly interact with solvent molecules.
Critical exponents for (methylcyclohexane + tetradecafluoromethylcyclohexane) from measurements of excess volumes at temperatures close to the critical mixing temperature
Authors: Kumaran MK , McGlashan ML
Published: September 2010

Molar excess volumes of (methylcyclohexane + tetradecafluoromethylcyclohexane)
have been determined as a function of composition at each of 15 temperatures
from 2 K above to 1.5 K below the critical mixing temperature (319.262 K). The
results have been analysed in terms of the critical exponents α, β,
and γ.
Reactions over supported metal catalysts. VI. The effect of halogen compounds on transition metal catalysts supported on silica or pumice. Reactions of 3-methylnortricyclene
Authors: Jackson WR , Nicolson DM
Published: September 2010

The product distributions
from reactions of 3-methylnortricyclene with hydrogen over palladium or
platinum catalysts supported on silica or pumice vary significantly after
treatment of the catalyst with small amounts of halogen-containing compounds.
Evidence is presented, including deuterium distribution studies utilizing 2H
N.M.R., that these changes in products are associated with intermediates which
have greater sp2 character at the reacting carbon atoms and that the
formation of intermediates is not simply associated with an increase in
catalyst acidity.
N.M.R. studies on myelin basic protein. IV. 13C N.M.R. of the peptide encephalitogenic in the guinea pig
Authors: Margetson SA , Moore WJ
Published: September 2010

The encephalitogenic
nonapeptide Phe1-Ser2-Trp3-Gly4-Ala5-Glu6-Gly7-Gln8-
Lys9 and its [D-Ala5] analogue have been studied in
aqueous solution by 13C n.m.r. spectroscopy. The resonances of all
the carbons have been assigned and their pH profiles measured. The expected
conformational differences are indicated by only subtle differences in
long-range pH titration shifts. The spin-lattice relaxation times T1
of all the protonated carbons of the [L-Ala5] nonapeptide have been
measured at 25°C. Analysis of these data in terms of effective correlation
times for side-chain mobilities suggests restricted motions for the side chains
of Glu6 and Gln8 and the aromatic rings of Phe1
and Trp3.
Stereochemical studies. VIII. Further studies of stereochemical effects on the course of oxidation of α-acyloctahydronaphthalenones
Authors: Middleton S , Stock LE
Published: September 2010

trans-Fused
octahydroindene-1- and -2-carboxylic acids are formed stereoselectively on
oxidation of α-acyl derivatives of trans-fused octahydronaphthalen-1(2H)-
and -2(1H)-ones by hydrogen peroxide.
Synthesis of a natural hexachloro dinaphthofuran quinone
Authors: Cameron DW , Feutrill GI , Pannan LJH
Published: September 2010

1,3,6,8,11,13-Hexachloro-4,10-dihydroxy-5,9-dihydrodinaphtho[2,1-
b:1',2'-d]furan-5,9-dione (1), a pigment isolated from soils and the only
natural example of this ring system, has been synthesized for the first time.
The computer simulation of the magnetic properties of paramagnetic molecules at low temperatures and/or high applied magnetic field strengths
Authors: Gregson AK
Published: September 2010

The commonly used form of
the Van Vleck equation to calculate the magnetic
susceptibility and effective magnetic moment of paramagnetic molecules does not
consider explicitly the applied magnetic field. It is pointed out that for low
temperatures and/or high magnetic field strengths this is not a good
approximation and that numerical methods are necessary. A computer program is
described and illustrated with a hypothetical S = 1 non-degenerate ground state
with zero-field splitting and the recently published example of a low spin d4
complex with C2v symmetry.
Fluorine magnetic resonance studies. V. Fluorine-fluorine coupling in 1,4-difluorobenzenes
Authors: Kerr CA , Quinn KJ , Rae ID
Published: September 2010

A number of substituted
1,4-difluorobenzenes were examined by 19F n.m.r. spectroscopy and 5JFF
was found to vary with the nature of the substituent in much the same way that
it does in more heavily substituted difluorobenzenes. Only in 2',5'-difluoroacetophenone
is 5JFF larger than it is for 1,4-difluorobenzene itself.
The magnitude of 5JFF is increased when a small ring is
fused to the benzene ring, i.e. in 4,7-difluorodihydroindenes and 2,5-difluorobicyclo[4,2,0]octa-1,3,5-
trienes. Similar effects have been reported for 5JHH in
aromatic systems, and the value of 5JHH for
tricyclo-[6,2,0,03,6]deca-1,3(6),7-triene is found to be 1.61 Hz.
Lewis-acid-catalysed reaction of oxygen with 1,3-diphenylisobenzofuran, tetraphenylfuran and tetraphenylcyclopentadiene
Authors: Haynes RK , Peters JM , Wilmot ID
Published: September 2010

1,3-Diphenylisobenzofuran
is converted into o-dibenzoylbenzene (40-70%) by oxygen, either in
dichloromethane at -78° in the presence of 1-2 equiv. of a variety of Lewis acids,
or on silica gel at 20°, in the dark. Tetraphenylfuran is converted into (Z)-dibenzoylstilbene
(55-65%) under the former conditions in the presence of 0.05 equiv. of I2
or SnI4 under irradiation from a tungsten lamp. The conversions,
which correspond to a mono-oxygenation process, do not involve as intermediates
the furan endoperoxides, which were independently generated from the furans by
use of singlet oxygen. 2,5-Dimethylfuran and p-menthofuran do not react with
oxygen in the presence of Lewis acids under the foregoing conditions. Tetraphenylcyclopentadiene is converted by oxygen into the
corresponding endoperoxide (70-85%) in the presence of 0.05 equiv. of I2
and SnI4 or 0.1 equiv. of Ph3C+BF4-
in dichloromethane at -78° under irradiation.
The protonation of 2,4-, 3,4- and 2,4,5-Polyalkylphenols in fluorosulfonic acid
Authors: Blackstock SM , Hartshorn MP , Richards KE
Published: September 2010

The protonations of 2,4-
and 3,4-dialkylphenols and 2,4,5- trialkylphenols and
anisoles, where the alkyl groups are ethyls or methyls, have been examined for
fluorosulfonic acid solutions at -50°. These investigations show that in these
systems C4-protonation ipso to an ethyl group occurs more readily than
protonation ipso to a methyl group.
Crystallization of liquids in the vicinity of a solid
Authors: Lane JE , Spurling TH
Published: September 2010

We present evidence, gained
from grand ensemble Monte Carlo simulations of the solid/liquid interface, that
an adsorbed layer of spherically symmetric liquid particles can have a
crystal-like structure even if the solid phase is structureless.
Lead thiolates. The formation of water-soluble lead(II) thiolates and the crystal structure of 2-(Morpholin-4-yl)ethanethiolatolead(II) nitrate
Authors: Dance IG , Guerney PJ
Published: September 2010

The solubilized
thiolate ligand 2-(morpholin-4-yl)ethanethiolate,
mes, and its ammonium conjugate acid, Hmes, form crystalline complexes Pb2(Hmes)3(N03)4, Pb(mes)2, Pb(mes)(N03),
Pb(mes)- (O2CCH3) and Pb(mes)(O2CCF3). These lead(II) thiolate complexes are soluble in aqueous media. Crystals
of Pb(mes)(NO3) contain chains of
alternating lead and bridging thiolate sulfur atoms
[Pb-S 2.646(4), 2.793(4) �], with the lead coordinated also by the tertiary
nitrogen atom [Pb-N 2.61(1) �]. The nitrate ions weakly bridge lead atoms along
the chain [Pb-O 2.69(2), 2.88(2), 2.98(2), 3.03(2) �]. Crystal data: Pbca, a
l3.396(2), b 21.900(3), c 7.348(1) �, Z 8(x PbSN2O4- C6H12),
1602 observed data, R 0.057.
A search for lone-pair interactions in forward and reverse Menschutkin reactions of some diaza heterocycles
Authors: Deady LW
Published: September 2010

The rates of methylation (forward reaction) of phthalazine (1), 1,8-naphthyridine (2), 1,10-phenanthroline
(3), and of some ring methyl derivatives are compared with the rates of demethylation of the corresponding N-methyl quaternary iodides. It was observed for (2), and
especially for (3), that a nitrogen lone pair in place of a CH group (quinoline
and 8-methylquinoline, respectively) aids the forward reaction but does not
have a commensurate retarding effect on the reverse process. In contrast to
(3), 2,2�-bipyridine showed behaviour typical of a-substituted pyridines. The introduction of a
2-methyl group into (3) had an appreciable rate-enhancing effect on methylation
(at N 10) and this is interpreted as evidence for lone-pair cooperativity
in the forward reaction.
Dissociation kinetics of metal complexes in acid. Copper complexes of triazamacrocycles
Authors: Graham PG , Weatherburn DC
Published: September 2010

The acid dissociation
kinetics of the mono-copper complexes of 1,4,7-triazacyclononane, znn; 1,4,7-triazacyclodecane, zdn;
1,4,8-triazacycloundecane, zud;
1,5,9-triazacyclododecane, zdd;
2,2,4-trimethyl-1,5,9-triazacyclododecane, tmzdd;
1,5,9-triazacyclotridecane, ztd; and cyclohexane-
r-1,c-3,c-5 triamine, ccha,
were studied in aqueous solution over a range of acid concentrations (0.025-0.5
mol dm-3), I 1.0 (NaN03). A variety of
kinetic behaviour is observed. Cu(znn)2+,
Cu(zdn)2+ and Cu(zud)2+
display a first-order dependence upon [H+] with kH (298 K) 51 dm3
mol-1 s-1 (znn), 17 dm3
mol-1 s-1 (zdn), and 5.6 dm3
mol-1 s-1 (zud). Cu(zdd)2+, Cu(ztd)2+
and Cu(ccha)2+ show a dependence on [H+]
at low acid concentrations but become acid-independent at high concentrations.
The acid-independent rate constants are k1 (298 K) 2.2 s-1
(zdd), 15.4 s-1 (ztd)
and k1 (283 K) 75 s-1 (ccha).
Cu(tmzdd)2+ shows a rate law of the form
rate = k+kH[H+] with
k (298 K) 1.8×10 s-1 and kH
(298 K) 2.0×10-3 dm3 mol-1 s-1.
Activation parameters have been determined in all cases except Cu(ccha)2+ which was studied at 10�C. The results
are compared with other macrocyclic complex systems,
and a general mechanism for these reactions is discussed.
Metal complexes of 1,10-phenanthroline derivatives. XII. Complexes of 2-Hydrazino-1,10-phenanthroline and related molecules
Authors: Abushamleh AS , Goodwin HA
Published: September 2010

2-Hydrazino- and 2-(N1-methylhydrazino)-1,10-phenanthroline
have been prepared from 2-chloro-1,10-phenanthroline and the appropriate
hydrazine. These tridentate chelating agents yield bis-(ligand) complexes with
nickel(II) and iron(II). Spectral data for the nicke(II)
complexes indicate that the field strength of the ligands is near the crossover
region for iron(II). Magnetic and M�ssbauereffect data indicate that a
5T2 ↔ 1A1
spin transition occurs in salts of the complex of the methylhydrazine
derivative, though a marked anion-dependence for this transition is observed.
Benzaldehyde hydrazone derivatives of both hydrazines
also yielded six-coordinate nickel (II) and iron (II) complexes, but these were
of significantly lower field strength than the parent hydrazines.
Bisphenol Flukicides. V. The Crystal and Molecular Structures of 2,2'-(2,2-Dichlorovinylidene)bis(4-chloro-6-nitrophenol) and 4,4'-(2,2-Dichlorovinylidene)bis(2-chloro-6-nitrophenol)
Authors: Hay D , Demunk P , Mackay M
Published: September 2010

Crystals of 2,2'-(2,2-dichlorovinylidene)bis(4-chloro-6-nitrophenol)
(1), C14H6C14N206, are
monoclinic and belong to the space group C2/c
with a 17.135(5), b 7.201(2), c 15.406(5) �, β 118.40(2)�, Z 4. Orthorhombic crystals of the
isomeric compound, 4,4'-(2,2-dichlorovinylidene)bis(2-chloro-6-nitrophenol)
(2), belong to the space group P bcn with a
20.410(3), b 8.682(2), c 18.716(3) �, Z 8. The structures were
deduced from diffractometer data. For (1), refinement with 956 terms measured
with Mo Kα radiation converged at R 0.055;
structure (2) was refined with 1475 terms measured with Cu Kα
radiation to R 0.079. Molecule (1) has exact C2 symmetry, and the
dihedral angle between the perpendiculars to the plane of the C-C-C bridge and
the phenyl rings of 84.2(4)� defines a butterfly conformation. The conformation
of (2) is twist with dihedral angles between the perpendiculars to the C-C-C
bridge and phenyl rings of 61 .9(7) and 33.0(7)�.
The measurement of the apparent nuclear spin-spin relaxation times of N.Q.R. signals in the ultra-high-frequency region
Authors: Bryant PJ , Hacobian S
Published: September 2010

Apparent spin-spin
relaxation times, T2*, for the 127I nuclear quadrupole
resonances of a series of substituted iodobenzenes were measured by the
Doolan-Hacobian double-pulse detection technique. A coaxial line oscillator
capable of operation to 800 MHz was used to obtain the signals of the higher
frequency transitions. It is shown that the ratio of the T2*
measurements of the lower to the upper transition in spin 5/2 systems is of the
order of two. This is in accordance with the assumption that the broadening is
mainly electrical in nature and arises from the spread in the principal
component of the electric field gradients produced by crystal defects.
Apparent molar volumes for selected nitrogen base complexes of Co3+, Ni2+ and Cu2+ at 298 K
Authors: Bottomley GA , Glossop LG
Published: September 2010

The apparent molar volumes
of aqueous solutions of seven alkyl diamines and two aromatic diamines, and 15
of their complexes with Co3+, Cu2+ and Ni2+
have been measured at 298 K over a wide concentration range down to 10-4
mol dm-3. Intercomparison is made of the ion, ligand and related
complex limiting apparent molar volumes which follow an additive rule. The
following pairs of complex ions, with similar geometric ionic radius and
structure but of opposite charge, [Co(en)3]3+ and [Co(ox)3]3-,
and [Co(ox)2(en)]- and [Co(en)2(ox)]+ (en =
ethylenediamine, ox = oxalate), show similar apparent ionic volumes, and
solvent electrostriction. Solutions of [Ni(en)3] Cl2
undergo considerable dissociation: the effective apparent molar volume is
analysed in terms of known dissociation constants and additional volumetric
data for the generated species. For the less dissociated [CO(NH3)6]Cl3,
logK6 is estimated to be 5.5 from the volumetric data.
2,1-Benzisothiazoles. XI. The rearrangement of 2,1-Benzisothiazol-3-yl esters. Autocatalysis of a sulfur extrusion by low-molecular-weight sulfur
Authors: Davis M , Tonkin KC
Published: September 2010

The extrusion of sulfur
from acyl derivatives of 2,1-benzisothiazol-3(1H)-one (1) is autocatalytic. The catalyst is low-molecular-weight
sulfur. Addition of cyclohexasulfur (5) to solutions of theseacyl derivatives increases
the rate of such reactions.
Bischler-Napieralski reaction of N-(4-Aryl-4-hydroxybutyl)benzamides: Synthesis and X-ray structure of (E)-3-arylmethylidene-4,5-dihydro-3H-pyrroles
Authors: Browne EJ , Skelton BW , White AH
Published: September 2010

The N-(4-aryl-4-hydroxybuty1)benzamides (3a,b) have been cyclized under
Bischler-Napieralski conditions to the
3-arylmethylidene-4,5-dihydro-3H-pyrroles (4a,b). These products are consistent with the formation of
N-(4-aryibut-3-enyl)benzamide intermediates. The structure of the
3,4-dimethoxyphenyl derivative (4a) was confirmed by X-ray crystallographic
analysis, which established its configuration as the E-isomer.
An investigation of the reaction of dehydrogenating agents with a stable 8-Oxatricyclo[4,3,0,07,9]nona-2,4-diene and related Bicylo[4,2,0]octa-2,4-dienes as a potential route to isobenzofurans
Authors: Tan RYS , Russell RA , Warrener RN
Published: September 2010

Reaction of the
7,8-dichlorobicyclo[4,2,0]octa-2,4-diene (9) with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone
yields the benzocyclobutene (10). Extension of this technique to the related
bicyclo[4,2,0]octa-2,4,7-trienes (21) and (23), or 8-oxatricyclo[4,3,0,07,9]nona-2,4-diene
(6) was unsuccessful. Manganese dioxide was equally unrewarding while o-chloranil reacted with these olefins to
yield benzodioxins in a [4+2] cycloaddition reaction.
Gallium-69, gallium-71 and indium-115 N.M.R. studies of Group 3 tetrahalometallate(III) anions
Authors: Colton R , Dakternieks D , Hauenstein J
Published: September 2010

Gallium-69 and -71 and
indium-115 n.m.r. spectra have been obtained for the tetrahalometallate anions
MX4- (M = Ga, In; X = Cl, Br, I) in dichloromethane
solution. For each element, mixtures of two halo anions gave mixed halo species
in the statistical distribution. For gallium, a mixture of the three halo
anions gave all 15 possible species in the statistical distribution. The effect
of the electric quadrupole moment is clearly reflected in the linewidths;
gallium-71 gave sharper lines and better resolution of the mixed species than
gallium-69 and the resonances for indium-1 15 were very broad.
The crystal structure of deuterated trans-Tetraamminedinitronickel(II) at 4.2 K by neutron diffraction
Authors: Figgis BN , Reynolds PA , Williams GA , Lehner N
Published: September 2010

The crystal structure of
deuterated trans-tetraamminedinitronickel(II),
Ni(ND3)4(NO2)2, has been determined
by single-crystal neutron diffraction methods at 4·2 K. Crystals are
monoclinic, C2/m, a 1058(l), b 672(1), c 586.3(3) pm, β 114.82(5)�, Z = 2. Diffractometry
has provided Bragg intensities for 219 independent reflections; and the
structure has been refined by full-matrix least-squares methods to R(F2)
0·070 and χ2 3·8. There are slight differences in the
molecular geometries determined by neutron diffraction and earlier X-ray
determinations of Ni(NH3)4(NO2)2 at
295 and 130 K. Small, but significant, decreases are evident in all
non-hydrogen bond lengths on decrease in temperature from 295 to 4·2 K, up
to a maximum of 2·0(4) pm for the Ni-NH3/ND3 bond.
The magnitudes of these decreases are correlated with the force constants of
the bonds. The intermolecular geometry and thermal parameters show that in the ab plane there is a network of relatively
strong, linear N-D···O hydrogen bonds. In the c* direction there
is a slightly bent, longer, N-D(1)···O bond which is weaker.
This causes a large amplitude of rigid-body translational motion in the c*
direction, together with high thermal motion of D(1) in the b axial direction.
A diterpene from Pityrodia lepidota
Authors: Ghisalberti E , Jefferies PR , Raston CL , Toia RF , White AH
Published: September 2010

A single-crystal X-ray
structure determination on the diacetate derivative of the major diterpene
ester isolated from the neutral extract of P. lepidota (Verbenaceae) has shown it
to be methyl (13E)-6α,18-diacetoxycleroda-3,13-dien-15-oate.
The formation of the anion from 1-Thiacyclohept-2-ene 1-Oxide and its reaction with substituted benzaldehydes
Authors: Crumbie RL , Ridley DD
Published: September 2010

On treatment with bases
1-thiacyclohept-2-ene 1-oxide affords the 2-metallated derivative which rapidly
polymerizes, except in the presence of tetramethylethylenediamine when the pale
yellow anion is relatively stable in tetrahydrofuran solution at - 78�. The
anion reacts rapidly with methyl iodide and with benzaldehyde and gives
2-methyl-1-thiacyclohept-2-ene 1-oxide and 2-(1-hydroxy-
1-phenylmethy1)-1-thiacyclohept-2-ene 1-oxide respectively in high yields.
Substituted benzaldehydes react similarly to benzaldehyde and whilst the ratio
of diastereomeric products formed is affected by the nature of the substituent,
no clear correlation emerges. The reactions are subject to kinetic control and
it is proposed that an unfavourable lone-pair, π-cloud electronic interaction is responsible for the
diastereoselection.
The synthesis of 1-Fluoro-4-methyl-1,2,3,4-tetrahydro-1,4-ethanonaphthalenes substituted in the arene ring
Authors: Adcock W , Abeywickrema AN
Published: September 2010

The main details of the
syntheses of a number of 6- and 7-substituted
1-fluoro-4-methyl-1,2,3,4-tetrahydro-1,4-ethanonaphthalenes are presented.
The synthesis of 2-heteroarylimidazo[1,2-a]pyridin-3-ols and related compounds
Authors: Deady LW , Stanborough MS
Published: September 2010

A reaction between
pyridin-2-amine 1-oxides and phenacyl bromides has been extended to some
bromoacetyl heteroaromatic compounds to form the title compounds. The reaction
of some 2-amino-diazine 1-oxides with phenacyl bromides has also been studied.
The imidazo[1,2-a]pyrimidine and imidazo[2,1-a]phthalazine systems have been
prepared but reaction of pyrazin-2-amine 1-oxide did not give the desired
cyclization.
The effects of bulky substituents in the reactions of alkynes with (η-C5H5)M(CO)2, M = Co or Rh
Authors: Corrigan PA , Dickson RS
Published: September 2010

The reactions between
(η-C5H5)Co(CO)2 and MeC≡CR
(R = Bu, Pri) at 120° gave the
cyclopentadienone complexes (η-C5H5)Co[C4Me2R2CO]
(2) and small amounts of the p-benzoquinone complexes(η-C5H5)Co[C4Me2R2(CO)2]
(1); all possible isomers of both complexes were obtained. For R = But,
the only products isolated were two isomers of the cyclopentadienone complex
(2). The reactions between (η-C5H5)Rh(CO)2 and MeC=CR at
160° gave the cyclopentadienone complexes(η-C5H5)Rh[C4Me2R2CO] (2), and
small amounts of the p-benzoquinone complexes (η-C5H5)Rh-[C4Me2R2(CO)2]
(1) and of the binuclear complexes (η-C5H5)2Rh2(MeC2R)2CO
(3). With R = But, three isomers of (2), two isomers of (1) and three isomers of
(3) were identified. The products obtained with R = Pri
were three isomers of (2) and three isomers of (3). With R = But,
three isomers of(2) and a very small amount of one of the isomers of (3) were
separated. Comparisons of these reactions have shown that increasing the bulk
of R results in a decrease in the total yields of products, a decrease in the
range of products, and a change in the distribution of the isomers (M = Co
only).
Pulse radiolysis of aqueous solutions of N-Vinylpyrrolidin-2-one and Poly(N-vinylpyrrolidin-2-one)
Authors: Davis JE , Sangster DF , Senogles E
Published: September 2010

The absorption spectra of
transient species produced when dilute aqueous solutions of N-vinylpyrrolidin-2-one
(vp) and poly(N- vinylpyrrolidin-2-one) (pvp) are subjected to pulse radiolysis in the presence and
absence of radical scavengers have been obtained and compared with those obtained
from analogous compounds. The precise structure of the transients has not been
established. Rate constants for the reaction of the hydroxyl radical with vp and pvp have been evaluated
both by a competition kinetic method and by direct observation of the build-up
of transient species: k(vp+·OH) =
(6.4-8.1) × 109 dm3 mol-1 s-1 and k(pvp+·OH) = (1.5-2.3) × 108 dm3
mol-1 s-1 at 25°C. The rate constant for the reaction of
the hydrated electron with vp has been determined
as(1.6�0.3) × 109 dm3 mol-1 s-1 at
25°C. Rate constants for decay of the transient species have also been
evaluated at 25°C: 2k(vp- OH·) =
(8.1�1.0)× 108 dm3 mol-1 s-1; 2k(vp-e-) = (1.7�0.2) × 109 dm3
mol-1 s-1 and 2k(pvp-OH·)
= (1.5�0.2) × 108 dm3 mol-1 s-1.
Quinones and quinone methides. VIII. Oxidation products of the screwworm chemosterilant, 2,4-Bis(1,1-dimethylethyl)-6-(4-methoxyphenylmethyl)phenol
Authors: Jurd L , Wong RY
Published: September 2010

The title compound is
oxidized by silver oxide in acetone to a complex mixture of products, including
the benzophenone derivative (7), a benzylic alcohol, isolated as its methyl
ether (15), and two spiro cyclohexadienone benzopyran dimers (17) and (19). A colourless
dimer was shown by single-crystal X-ray diffraction measurements to be a 2,3- dihydrobenzofuran
derivative (22).
Reactions of acyl phosphates. Base hydrolysis of [Co(NH3)5OPO3COCH3]+ and the metal hydroxide promoted hydrolysis of acetyl phenyl phosphate
Authors: Buckingham DA , Clark CR
Published: September 2010

Tracer 18O
studies have established that base hydrolysis of coordinated acetyl phosphate
in [(NH3)5Co-OPO3COCH3]+
(kOH 0.53 mol-1 dm3 s-1, 25°C, I
1.0 NaClO4) proceeds with exclusive carbon-oxygen bond fission. The
hydrolysis of acetyl phenyl phosphate monoanion is significantly catalysed by
the exchange-inert hydroxo complex [(NH3)5Co-OH]2+
(kMOH 2.9 × 10-2 mol-1 dm3 s-1,
25°) which operates through a nucleophilic pathway involving attack at carbonyl
carbon.
The constituents of Australian Pimelea species. II. The isolation of unusual flavones from P. simplex and P. decora
Authors: Freeman PW , Murphy ST , Nemorin JE , Taylor WC
Published: September 2010

Extraction of Pimelea
simplex F. Muell. and P. decora Domin.
has yielded flavone and several methoxyflavones of unusual oxygenation
patterns: 2'-methoxyflavone and 7-methoxyflavone from P. simplex, and 3'-methoxyflavone,
6-methoxyflavone, 3',6-dimethoxyflavone and 2',3',6- trimethoxyflavonefrom
P. decora. The structures of the substances were confirmed by synthesis from
the corresponding chalcones. The 13C n.m.r, spectral data of the
flavones and chalcones are tabulated.
Temperature dependence of apparent molar volumes of electrolytes related to water compressibility
Authors: Bottomley GA , Glossop LG
Published: September 2010

Ellis's published
information on the limiting apparent molar volumes of 17 electrolytes in water
is here shown in most cases to be a closely linear function of the solvent's
isothermal compressibilityfrom 75°C to 200�C, with
different slopes for the 1 : 1 and 2 : 1 electrolytes.
Structural and spectroscopic studies of transition metal nitrite complexes. I. Crystal structures and spectra of trans-Bis(ethane- 1,2 diamine)dinitronickel(II), trans-Bis[N, N-dimethyl(ethane- 1,2-diamine)]dinitritonickel(II) and trans-bis[N,N'-dimethyl(ethane-1,2 diamine)]dinitronickel(II) monohydrate
Authors: Finney AJ , Hitchman MA , Raston CL
Published: September 2010

The crystal structures of
the trans complexes
bis(ethane-1,2-diamine)dinitronickel(II) (1), bis[N,N-dimethyl(ethane-1,2-diarnine)]dinitritonickel(II) (2) and bis[N,N'-dimethyl(ethane-1,2-diamine)]dinitronickel(II)
monohydrate (3) are described, (1) and (2) being redeterminations of previously
reported structures. The complexes formed by the substituted amines have
significantly different geometries, both in the manner of coordination of the
nitrite ligands, and in the conformations adopted by the diamine chelate rings.
These differences can be explained in terms of the particular steric
requirements of the amine substituents. The changes in nitrite geometry which
occur upon coordination, and the spectroscopic properties of the complexes are
discussed.
The electrochemistry of the nickel sulfides. I. NiS
Authors: Power GP
Published: September 2010

The electrochemical
behaviour of NiS (synthetic millerite)
is examined by cyclic voltammetry and coulommetry at rotating disc and ring-disc electrodes. In
contrast to a previous study, the passive layer on NiS
is shown to be a mixture of sulfur and a nickel-deficient nickel sulfide. This
layer is shown to be conductive to electrons but not to nickel ions. The
formation of an insulating layer of elemental sulfur at higher potentials is
demonstrated, while rapid dissolution of the mineral to form Ni2+(aq) and oxy anions of sulfur is observed at greater than +
1 V (s.c.e.).
Substituent effects on the N.M.R. spectra of carboxylic acid derivatives. II. 3H N.M.R. spectra of substituted benzamides and N-alkylbenzamides
Authors: O'Conner CJ , Martin RW , Calvert DJ
Published: September 2010

The tritium n.m.r. spectra of 12
substituted benzamides and five series of N-alkylbenzamides have been measured, after tritiation of the amides, and the chemical shifts, δN3H, have been compared with δNH. The values correlate well when σR(BA) is substituted in the Taft DSP equation. Good correlations are also
obtained with the Hammett σ parameter. The
non-equivalence of the two amido protons of
benzamides, arising from the barrier to rotation round the carbon-nitrogen
bond, has been confirmed by use of triton n.m.r. spectroscopy.
Synthesis of substituted tetrafluorocyclobutanes. II. Monosubstituted aryl esters
Authors: Johnson WMP , Holan G
Published: September 2010

This paper describes the
essential features of the synthesis of several 1-substituted
2,2,3,3-tetrafluorocyclobutanes. The
1-substituents are aryl-substituted acetic and propanoic acid esters.
Triazolopteridines. II. Simple s-Triazolo[3,4-h]pteridines and some [5,1-h] and [4,3-a] isomers
Authors: Brown DJ , Shinozuka K
Published: September 2010

Pteridin-7-ylhydrazine (lb)
reacted with appropriate ortho esters to give s-triazolo[3,4-hlpteridine
(2a) and its 9-methyl derivative (2b). The same hydrazine with carbon disulfide
in pyridine gave the 9-thione (2c) and thence the methylthio
(2d) and dimethylaminoethylthio derivative (2e). The parent heterocycle
(2a) did not undergo Dimroth rearrangement to its
[1,5-h] isomer (3) but the latter was
made from pteridin-7-ylamine (1c) via its dimethylaminomethyleneamino (1d) and hydroxy- aminomethyleneamino (1e) derivatives.
Pteridin-2-ylhydrazine (1f) and triethyl orthoformate gave a single product shown by 1H
and 13C n.m.r. data to be s-triazolo[4,3-a]pteridine (4a) rather than its [3,4-b] (5), [1,5-a] or
[5,1-b] isomer. The 9-methyl (4b) and 9-ethyl (4c) derivatives were made
similarly.
Spermidine derivatives and 9,11-secosteroids from a soft coral (Sinularia sp.)
Authors: Kazlauskas R , Murphy PT , Ravi BN , Sanders RL , Wells RJ
Published: September 2010

The structures of two new N-methylated spermidine
amides, (4) and (5), isolated from a soft coral (Sinularia sp.) are described
together with the synthesis of one of them. Two new 9,11-secocholestane
derivatives, (6) and (7), have also been isolated from the same organism.
Lipid and terpenoid metabolites of the Gorgonian Plexaura flava
Authors: Ravi BN , Wells RJ
Published: September 2010

Six novel branched-chain
lipids containing a γ-lactone ring have been isolated from the Gorgonian Plexaura flava. These
compounds were accompanied by two new terpenoids of
mixed biosynthesis.
A blue pigment from a compound ascidian
Authors: Kazlauskas R , Marwood JF , Murphy PT , Wells RJ
Published: September 2010

A deep blue pigment, isolated from a Western
Australian compound ascidian, has been shown to be
identical to a tetrapyrrole reported from a mutant strain of a bacterium.
Statistical mechanics of deuterium exchange reactions : relationships between equilibrium constants and enthalpies of reaction
Authors: Fenby DV , Bertrand GL
Published: September 2010

Bertrand and Burchfield
proposed that the equilibrium constants K and the (standard) enthalpies ΔH
of isotopic exchange reactions are related by the equation
K = Kstatexp(-ΔH/RT)
in which Kstat is the statistical (random)
equilibrium constant. The application of this equation to deuterium exchange
reactions for which experimental K and ΔH values are available suggests
that it is a good approximation at 298 K. In this paper we present a
statistical mechanical analysis to account for the success of the equation and
to point out its limitations.
Orbital interactions. XI. Application of photoelectron spectroscopy to the study of orbital interactions in some 2- and 9-substituted octahydrodimethanonaphthalenes
Authors: Paddon-Row MN , Patney HK , Brown RS
Published: September 2010

The photoelectron spectra of some 2- and
9-substituted (1x,4x,4aβ,5β,8β,8aβ)-1,2,3,4,4a,5,8,8a-octahydro-1,4:5,8-dimethanonaphthalenes,
(1)-(6), and (12), and their perhydro analogues,
(1')-(6'), and (12'), were obtained in order to assess the magnitude and nature
of orbital interactions in these molecules. The πcc Ip of the ketone (12) was found to be 0.1 eV
higher than that of the hydrocarbon (1) and is thought to be due to the
presence of orbital interactions through bonds in the former molecule. Through-space
and through-bond interactions in the ketone (6) are responsible for increasing
the πcc Ip by 0.33 eV
with respect to that of (1) whereas through-space interactions are solely
responsible for the lowering of the πcc Ip
of the syn-ether
(5) 0.36 eV with respect to the anti
isomer (3).
Strong intramolecular OH…π bonding in the alcohol (4)
results is an increase in πcc by 0.33 eV and a decrease in the no
Ip by 0.42 eV both with respect to the corresponding ionizations in the anti-alcohol (2).
The chemistry of pyrrolic compounds. L. The synthesis of oxorhodoporphyrin dimethyl ester and some of its derivatives
Authors: Clezy PS , Crowley RJ , Hai TT
Published: September 2010

Oxorhodoporphyrin dimethyl ester, a porphyrin containing electronegative groups in
opposite pyrrolic rings, has been synthesized by the oxidative cyclization of a
bilene-b. Rhodoporphyrin and its
2-vinyl analogue, two important degradation products of chlorophyll a, and the
phaeopor- phyrin derivative of bacteriochlorophyll have been prepared from
oxorhodoporphyrin.
Dehydration studies of α- and β-ionol. I. With hexamethylphosphoric triamide
Authors: Whitfield FB , Sugowdz G
Published: September 2010

α-Ionol (2) when
heated under reflux with hexamethylphosphoric triamide gave principally one
product (1'E)-6-(buta-1',3'-dienyl)-1,5,5-trimethylcyclohex-1-ene
(4a) together with trace quantities of the (1'Z)-isomer (4b). Under similar
conditions β-ionol (3) gave as major products (6E,2'E)- and
(6Z,2'E)-6-(but-2'-enylidene)-1,5,5-trimethylcyclohex-1-ene (1a) and (1b)
together with smaller quantities of
(1'E)-1-(buta-1',3'-dienyl)-6,6-dimethyl-2-methylenecyclohexane (8) and
1,1,6-trimethyl- 1,2,3,4,5,6-hexahydronaphthalene (9). Minor products from this
reaction included the isomeric trienes (1c) and (1d). Reaction pathways are
suggested for the formation of all identified products.
Hyperfine interactions in methanimine
Authors: Brown RD , Godfrey PD , Winkler DA
Published: September 2010

A high-resolution study of
hyperfine splitting in the microwave spectrum of methanimine
has yielded the following values (in MHz) for 14N hyperfine
constants: xaa- 0.898(8), xbb - 2.693(8), xcc
3.591(8), Ca -0.0495(47), Cb -
0*0097(27), Cc -0.0012(24). The localized theory for calculation of
the magnetic hyperfine constants appears generally to overestimate Cc
by an order of magnitude for molecules structurally similar to methanimine.
Cluster chemistry. VI. Reactions of Ru3(CO)11(CNBut) with hydrogen
Authors: Bruce MI , Wallis RC
Published: September 2010

The reaction between Ru3(CO)11(CNBut)
and hydrogen affords the μ3-formimidoyl complex Hru3(μ3-HCNBut)(CO)9
(2) as the major product; also formed are Hru3(μ-HCNBut)(CO)8-
(CNBut), and the tetranuclear clusters H4Ru4(CO)12-n(CNBut)n
(n = 0, 1 and 2). Hydrogenation of Ru3(CO)10(CNBUt)2
gives higher yields of HRu3(μ-HCNBut)(C0)8(CNBut)
and H4Ru4(CO)10-(CNBut)2. Reactions between H4Ru4(CO)12
and CNBut to give H4Ru4(CO)12-n(CNBut)n.
(n = 1, 2 and 4) are also described.
Ab initio studies on amides: acetamide, N-methylformamide and N-methylacetamide
Authors: Radom L , Riggs NV
Published: September 2010

Ab initio molecular
orbital theory with the STO-3G and 4-31G basis sets has been used to
investigate the geometries, preferred conformations, and barriers to internal
rotation for acetamide, N-methylformamide and N-methylacetamide. Results are
compared with corresponding previously reported data for formamide. For
acetamide, the preferred conformation has the methyl group staggered with
respect to the N-C bond whereas for N-methylformamide the methyl group is
eclipsed with respect to this bond. Both N-methylformamide and
N-methylacetamide prefer a Z-arrangement, i.e. methyl cis to C=O about the N-C bond. Experimentally determined barriers
to internal rotation about the N-C bond generally lie within the range spanned
by the STO-3G and 4-31G estimates.
The mechanism of extraction of zinc(II) from aqueous chloride solutions into chloroform solutions of methyltrioctylammonium chloride
Authors: Daud H , Cattrall RW
Published: September 2010

The mechanism of the
transfer of zinc(11) between 1.0 M HCl, 6.0 M HCl and 6.0 M LiCl and methyltrioctylammonium
chloride in chloroform has been studied by using the single-drop technique. It
is suggested that interfacial complexes are formed by fast ion-exchange
reactions and that the rate-determining step, in the case of 1.0 M HCl and 6.0 M LiCl, involves the
replacement at the interface of the complex R2ZnCl4 by
two molecules of reagent from the bulk organic phase. For 6.0 M HCl the rate-determining step is the replacement of the
interfacial complex RHZnCl4 by one molecule of reagent from the bulk
organic phase. Support for this mechanism is obtained by comparing the
extraction equilibrium constants for the complex R2ZnCl4 for 1.0 M HCl and 6.0 M LiCl from previous
with the values calculated from the rate data. Interfacial tension measurements
have shown that the interface is saturated with reagent over the full range of
concentrations studied.