bluuebunny/crossref_metadata_2025 huggingface dataset:
Alkylation of salts of pyridinols, quinolinols and isoquinolinols
Authors: Deady LW , Finlayson WL , Potts CH
Published: September 2010

The ratio of N- to O-alkylation
has been determined for reaction of the sodium salts of pyridin-2-ol,
6-methylpyridin-2-ol, pyridin-4-ol, quinolin-2-ol, quinolin-4-ol,
2-methylquinolin-4-ol, isoquinolin-1-ol and 3-methylisoquinolin-1-ol with ethyl
iodide and diethyl sulphate in aprotic solvents. N-Alkylation is generally
favoured. Reaction at the nitrogen is subject to steric hindrance by adjacent
groups (methyl or benzo), but in the benzo-fused compounds this effect is
opposed by an electronic one arising from the naphthalene nature of the
compounds. This results in a greater charge density on the nitrogen than is the
case in the analogous pyridines.
β-Amino ketoximes: a study of basicity, hydrogen bonding and isomerism
Authors: Powell HK , Russell JM
Published: September 2010

The protonation reactions
of the diamine dioxime 4,4,9,9-tetramethyl- 5,8-diazadodecane-2,11-dione
dioxime and its O-methyl and bis-O-methyl ethers have been studied at 25�, I
0.10 M NaCl. The (substituted) oxime groups cause a
marked reduction in the basicity of the secondary amino groups. log K
(potentiometric) and ΔH (calorimetric) data are interpreted in terms of
inductive effects of the oxime group and possible intramolecular hydrogen
bonding, N+-H...N(OR)=, pKa for methoxy-amine, NH2OMe,
has been determined (4.62�0.01, I 0.10 M NaCl, 25�). ������ P.m.r. spectra
are assigned for β-amino ketoximes having α- methyl and α-methylene
groups cis and trans to =N-OR groups. Infrared spectra are reported.
Experiments directed towards the synthesis of anthracyclinones. I. Synthesis of 2-formylmethoxyanthraquinones
Authors: Roberts JL , Rutledge PS , Trebilcock MJ
Published: September 2010

For substituted
anthraquinones methods are reported which allow the oxidation of a β-methyl
to a formyl group when the α- or both the ortho positions contain
protected hydroxyls.
The bromination of some N,N-dimethylanilines with dibromoisocyanuric acid
Authors: Rosevear J , Wilshire JFK
Published: September 2010

The reaction of some
representative N,N-dimethylanilines with dibromoisocyanuric acid has been
investigated. In many cases, mixtures of brominated products were obtained;
these mixtures were analysed both by gas-liquid chromatography and by proton
magnetic resonance spectroscopy. With excess of reagent, perbromination was
readily achieved. ��� Significant solvent shifts [δ(CDCl3)-δ(C6D6)]
were observed for a wide variety of bromo-N,N-dimethylanilines. This solvent
shift phenomenon was used not only for the assignment of structure to reaction
products but also for the quantitative analysis of mixtures of bromo-N,N-dimethylanilines.
Polysaccharides of tropical pasture herbage. VII. Identification of a new pinitol galactoside from seeds of Trifolium subterraneum (subterranean clover) and analysis of several pasture legume seeds for cyclohexitols and their galactosides
Authors: Beveridge RJ , Ford CW , Richards GN
Published: September 2010

A pinitol galactoside
isolated from ethanol extracts of seeds of T. subterraneum
has been shown to be 1D-2-O-(α-D-galactopyranosyl)-4-O- methy-chiro-inosito (1). The structure is based on
successive periodate oxidation, borohydride reduction, hydrolysis and
acetylation (Smith degradation), yielding the tetraacetate of 2-O-methyl-L-xylitol.
The seeds of 39 pasture legumes from 13 different genera and 26 species have
been analysed by gas chromatography for (1), myo-inositol,
D-(+)- pinitol and galactinol.
Experiments directed towards the synthesis of anthracyclinones. III. β-Formylation of hydroxyanthraquinones by the Claisen rearrangement
Authors: Roberts JL , Rutledge PS
Published: September 2010

β-Formylation of an
α-hydroxyanthraquinone is shown to be possible by way of thermally induced
rearrangement of the allyl ether, migration of the olefinic bond, and
ozonolysis.
Reaction of 5-Chloroalkyl-3-phenyl-4,5-dihydroisoxazoles with strong base. An unexpected new synthesis of the 2-Oxa-3-azabicyclo[3,1,0]hex-3-ene ring system
Authors: Burrowes TG , Jackson WR , Faulks S , Sharp I
Published: September 2010

Reaction of
5-chloromethyl-3-phenyl-4,5-dihydroisoxazole with potassium t-butoxide in
dimethyl sulphoxide gives 4-phenyl-2-oxa-3- azabicyclo[3,1,0]hex-3-ene
in high yield and reaction of the 5-(1?- chloroethyl) homologue gives high
yields of the diastereoisomeric 6- methyl derivatives of the bicyclic system.
Some unsuccessful attempts to convert these bicyclic compounds into substituted
cyclo-propanols and cyclopropenes are described.
Exciplex fluorescence in heterocycle acceptor complexes
Authors: Harman PJ , Nott PR , Selinger BK
Published: September 2010

A number of heterocyclic
acceptor excited-state (exciplex) complexes with N,N-diethylaniline have been
examined. In general their behaviour is consistent with the accepted theories.
Spectral shift sand intensity changes with solvent and radiationless deactivation
appear to be more complicated than with aromatics. The bipyridyls are discussed
in some detail.
Influence of pressure on the rates of deuteration of formate and acetate ions in liquid D2O
Authors: Hamann SD , Linton M
Published: September 2010

We have examined the
effects of hydrostatic pressures to 8 kbar on the
rates of deuteration of formate and acetate ions in pure D2O at temperatures
between 160 and 200�C. The formate reaction is only slightly accelerated by
pressure (the activation volume ΔVo?, at zero
pressure, is -2.5 cm3 mol-1). This fact disproves
mechanisms that have been proposed previously for the reaction and we propose
an alternative, concerted, molecular mechanism that fits the facts. By
contrast, the acetate reaction is significantly accelerated by pressure
(ΔVo? = -10.5 cm3 mol-1),
which is consistent with its occurring by mixed molecular and carbanionic
mechanisms.
Aluminium corrosion studies. III. Chloride adsorption isotherms on corroding aluminium
Authors: Berzins A , Lowson RT , Mirams KJ
Published: September 2010

The adsorption isotherms
for chloride on a corroding aluminium surface have been measured by using 36Cl
as a radioactive tracer. The amount of chloride adsorbed, wCl, was a
function of chloride concentration, [Cl], and time,
t, according to

������������ �����������log WCl = 0.64(log[Cl]+log t)-7.8

where wCl is
expressed as g cm-2, [Cl] as mol l-1
and t as minutes. Superimposed on the general curve was a fine structure which
correlated with the stages of development of a corroding aluminium surface. The
adsorption was localized to corroding pit sites. Addition of nitrate or
sulphate delayed but did not prevent the uptake of chloride; the hydroxide ion
was considered to have a similar effect. It was concluded that a corroding
aluminium surface has a variety of adsorption sites with different adsorption
properties; only a minority of these sites are potential or active sites for
pitting corrosion.
Crystal structures of trans-Dichloro- and Dibromo-bis(2,6-dimethylpyridine)copper(II)
Authors: Campbell JA , Raston CL , Varghese JN , White AH
Published: September 2010

The crystal structures of
the title compounds have been determined at 295(1) K by X-ray diffraction and
refined by full-matrix least squares to residuals of 0.045 and 0.067 for 1224
and 1955 ?observed? reflections respectively. The compounds are isomorphous
(triclinic, Pī, Z 1). Dichloro compound: a 8.068(2),
b 8.024(2), c 7.646(2) Ǻ, α 93.84(2), β 113.44(2), γ
117.11(2)�. Dibromo compound: a 7.999(2), b 7.921(2), c 7.849(2) Ǻ, α
94.37(2), β 112.85(2), γ 115.99(2)�. The copper atoms are
square-planar coordinated with two halide and two base ligands coordinated
necessarily trans by virtue of the siting of the molecule on a centre of
symmetry. Cu-X, Cu-N are 2.264(2), 2.011(3) (dichloro); 2.425(1), 1.997(4)
Ǻ (dibromo). The plane of the lutidine is almost normal to the CuN2X2
plane.
Studies in heterocyclics. III. Synthesis of thiazolotriazepines
Authors: Mahajan MP , Sondhi SM , Ralhan NK
Published: September 2010

Thiazolo[2,3-c][1,2,4]triazepines
have been synthesized by the condensation of thiazol-2-ylhydrazines with
requisite 1,3-diketones and a β-keto ester.
Studies in heterocyclics. IV. Synthesis of benzopyrimidothiadiazepines
Authors: Mahajan MP , Sondhi SM , Ralhan NK
Published: September 2010

N-[2-(2-Mercapto-4,4,6-trimethyl-1,4-dihydropyrimidin-1-
yl)phenyl]alkanamides (4), obtained by the acylation
of their amino analogues (3) with alkanoic acids, were cyclodehydrated to the
3H- benzo-[d]pyrimido[2,1-b][1,3,6]thiadiazepines (5).
Reactions of Perimidin-4-ones and -6-ones with amines
Authors: Cameron DW , Samuel EL
Published: September 2010

π-Deficient
perimidin-4- and -6-one systems reacted readily with primary and secondary
amines at room temperature. Nucleophilic attack occurred not only at the enone
double bond, but also at positions 7 and 9 on the benzenoid ring. Highly
coloured mono-, di- or tri-aminated derivatives were
thereby obtained. A significant degree of bond fixation was indicated.
Side-chain amination of 9-methyl substituents was observed, analogous to
processes encountered in quinone chemistry. On continued contact with amine the
products were converted partly into 9-formyl derivatives and partly into
9-amino compounds.
Crystal structures of rac- and meso-o-Phenylenebis(iodomethylarsine), the latter as its lattice complex with the methiodide of 1,3-Dimethyl-1,3-dihydro-2,1,3-benzoxadiarsole
Authors: Henrick K , Raston CL , White AH , Wild SB
Published: September 2010

The crystal structures of
the title compounds, o-C6H4(AsMeI)2
(1), and o- C6H4(AsMeI)2-
[o-C6H4(AsMe)(As+Me2)O]
I- (2), have been determined at 295 K by single-crystal X-ray
diffraction and refined by least squares to residuals of 0.037 and 0.067 for
2095 and 2913 reflections respectively. Crystals of (1) are triclinic, Pī, a 9.865(5), b 9.837(7), c 7.765(4) Ǻ, α
98.89(5), β 96.71(4), γ 60.72(4)�, Z 2.  is 2.585
Ǻ and  1.97 Ǻ. The angles about the arsenic differ only
trivially, the mean being 98.4�. Crystals of (2) are monoclinic, P21/n,
a 15.315(4), b 21.511(8), c 7.952(2) Ǻ, β 98.19(2)�, Z 4. In the
cation As-O distances are unequal [1.75(1) (quaternary As), 1.86(2) Ǻ];
As-O-As is very small being 115.8(8)�. Charge-transfer interactions between
iodine species are present in both derivatives; in (2), there is an interaction
between the tertiary arsenics of the meso molecule and the iodide anion, As...I
being 3.307(3), 3.551(3) Ǻ, with the geometry of the arsenics approaching
that of a tetrahedral disposition. Within the cation, the geometry about the
quaternary arsenic is typical of arsenic(v), the bond lengths being shorter
than those about the ternary arsenic.
The coordinating power of oxime, oximato and O-methyloxime donor groups: The stability of copper(II) complexes
Authors: Powell HKJ , Russell JM
Published: September 2010

The relative donor powers
of oxime and O-methyloxime groups have been assessed from the stability of
their coordination complexes with copper(II). The order of donor strengths
observed is oximato >> oxime > O-methyloxime.
Preparation and characterization of some stereochemically rigid seven-coordinate cyclopentadienylzirconium(IV) Tris-N,N-dialkyldithiocarbamate complexes
Authors: Jain VK , Garg BS , Singh RP
Published: September 2010

Zirconium(IV) N,N-dialkyldithiocarbamates of the type CpZr(S2CNR2)3
where R = Me, Et have been prepared by reaction of dicyclopentadienylzirconium(IV)
dichloride with sodium salts of substi- tuted dithiocarbamic acids in aqueous and non-aqueous
media. They have also been prepared by reaction of cyclopentadienylzirconium(~)
trichloride with sodium salts of substituted dithiocarbamic acids in
non-aqueous medium. Conductance and infrared studies show that these complexes
are non-electrolytes in which all of the dithiocarbamate ligands are bidentate.
Therefore, a coordination number of ?seven? may be assigned to the zirconium(IV)
atom in these compounds. Proton N.M.R. spectra of these complexes in carbon
disulphide or deuterated chloroform indicate that there is hindered rotation
about C-N single bonds at ambient temperature, and that metal-centred rearrangement
is slow on the N.M.R. time scale at ambient temperature (30�).
A synthesis of 2,2,2-Trichloroethyl 2-Acetamido-3,6-di-O-acetyl-2-deoxy-β-D-glucopyranoside
Authors: McLaren JM , Stick RV , Webb S
Published: September 2010

The conversion of
2-acetamido-2-deoxy-D-glucose into 2-acetamido-3,4,6-
tri-O-acetyl-2-deoxy-α-D-glucosyl chloride has been reinvestigated and the
chloride transformed, with some modification of the literature method, into
2,2,2-trichloroethyl 2-acetamido-4,6-O-benzylidene-2- deoxy-β-D-glucoside.
This compound has been converted into the title compound by the sequence
acetylation, acid hydrolysis and selective acetylation. An efficient synthesis
of benzyl 2,3-di-O-acetyl-β-D- galacto-pyranosideis
reported and its unsuccessful selective acetylation contrasted with the above.
Crystal structure of Carbonatohydroxo(2,2':6',2'-terpyridyl)cobalt(III) tetrahydrate
Authors: Kucharski ES , Skelton BW , White AH
Published: September 2010

The crystal structure of
the title compound, [Co(terpy)(CO3)(OH)],4H2O,
has been determined at 295 K by single-crystal X-ray diffraction and the use of
diffractometer data, and refined by least squares to a residual of 0.075 for
1354 ?observed? reflections. Crystals are triclinic, Pī,
a 11.407(6), b 10.566(6), c 8.445(4) Ǻ, α 100.21(5), β
107.35(5), γ 102.18(5)°, Z2. The structure of the molecule is unusual for
a 1 : 1 transition metal/terpy complex in that the other ligating atoms are
non-halide and the complex six-coordinate. The remaining three coordination
positions about the metal are occupied by the bidentate carbonate (Co-O
1.918(9), 1.918(8) Ǻ) and the hydroxide ion (Co-O 1.894(10) Ǻ). The
Co-N distances are appreciably shorter than those observed in other terpy
systems (Co-N(central) 1.848(8); Co-N(outer) 1.946(9), 1.952(9) Ǻ).
The structures of the Isoxazoles and 5-Isoxazolinones formed on irradiation of 3β-Acetoxy-6-nitrocholest-5-ene and 6-Nitrocholest-5-ene
Authors: Pinhey JT , Rizzardo E , Smith GC
Published: September 2010

.The two heterocyclic
compounds produced on irradiation of 3β-acetoxy-6- nitrocholest-5-ene (1) have
been shown by chemical degradation to be 3β-acetoxycholest-4-eno[6,5,4-cd]isoxazole
(3) and 3β-acetoxy-A- norcholestano[6,5-c]-2'-isoxazoin-5'-one (4), while
those formed from 6-nitrocholest-5-ene (2) are the analogous compounds,
cholest-4-eno[6,5,4-cd]isoxazole (5) and A-norcholestano[6,5-c]-2'-isoxazolin-5'-
one (6).
An attempted synthesis of the 5,6-Dihydrocyclobuta[l]phenanthrene system by a Thorpe cyclization
Authors: Craig JT , Halton B , Officer DL
Published: September 2010

Methyl 10-cyanomethylphenanthrene-9-carboxylate
(1e) has been subjected to conditions known to favour Thorpe cyclization, but
the desired 5,6- dihydrocyclobuta[l]phenanthrene
system (3) was not obtained. An alternative cyclization to give
3-ethoxydibenzo[f,h]isoquinolin-1(2H)- one (4)
occurs.
Synthesis and structure of tetraethylammonium (Dithiocarbonato-S,S')-bis(ethylxanthato)colbaltate(III)
Authors: Raston CL , White AH , Winter G
Published: September 2010

The title compound, (Et4N)
[Co(S2CO)(S2COEt)2], and its chromium analogue
have been prepared by nucleophilic attack of (Et4N)(S2COEt)
on the parent tris(ethylxanthato)metal(III) complex in acetone solution, the
structure of the cobalt derivative being confirmed by single-crystal X- ray
structure determination; the structure was refined by least squares to a
residual of 0.045 for 2306 'observed' reflections. Crystals are orthorhombic, P
bca, a 17.303(8), b 16.970(6), c 16.052(6) Ǻ, Z
8.  for the ethylxanthate ligands is 2.286 Ǻ,
longer than in the parent tris(ethylxanthato)-cobalt(III) complex, while
 for the dithiocarbonate, chelated through the two sulphurs, is
2.251 Ǻ.
Some Friedel-Crafts reactions of γ-butyrolactone
Authors: Kerr CA , Rae ID
Published: September 2010

Benzene reacts with γ-butyrolactone
and aluminium chloride to give tetralone, but no detectable amount of
3-methylindan-1-one. p-Dichlorobenzene, p-difluorobenzene and
m-dichlorobenzene give exclusively the indanones in good yield. Chlorobenzene
gives a mixture of tetralones and indanones in ratio 78 : 22 and the major
product of each type arises from alkylation ortho to chlorine. γ-Butyrolactone
is isomerized to crotonic acid by treatment with excess aluminium chloride at
150° and the indanones probably arise by this route.
Purine analogues as amplifiers of phleomycin. II. Some s-Triazolo[4,3-a]pyridines, s-Triazolo[4,3- or 1,5-a]pyrimidines and s-Triazolo[3,4-b]benzothiazoles
Authors: Brown DJ , Dunlap WC , Grigg GW , Danckwerts L , Nagamatsu T
Published: September 2010

s-Triazolo[4,3-a]pyridine-3(2H)-thione
(1b) undergoes S-alkylation to give derivatives such as
2-(s-triazolo[4,3-a]pyridin-2'-ylthio)acetamide (4c)
which may be oxidized to the corresponding sulfoxide (4g) and sulfone (4h).
Likewise, alkylation of 1-methyl-s-triazolo[4,3-a]pyridinium-3-thiolate (2b)
yields 3-carbamoylmethylthio-1-methyl-s-triazolo[4,3-a]pyridinium chloride
(3). ��� Similar treatment of
s-triazolo[4,3-a]pyrimidine-3(2H)-thione (1c) leads to
2-(s-triazolo[4,3-a]-pyrimidin-3'-ylthio)acetamide (4j) and analogues, all of
which undergo Dimroth-like rearrangement to their respective [1,5-a]-isomers
(5), (6b) and analogues. 2-(s-Triazolo[3,4-b]benzothiazol-3'-ylthio)acetamide
(9b) was also prepared from the corresponding thione (8). ��� Activities of the above compounds as
amplifiers of phleomycin against E. coli are tabulated. The amide (4c) is
highly active, non- toxic and resistant to metabolism.
The crystal structure of the methyl-bridged yttrium-aluminium complex, [(η-C5H5)2YMe2AlMe2]
Authors: Scollary GR
Published: September 2010

A structural analysis of
[(η-C5H5)2YMe2AlMe2]
has been carried out by X- ray diffraction. Crystals are orthorhombic, space
group Pna21, a 17.969(6), b 7.988(4), c 10.870(4) Ǻ, Z 4. The
structure has been refined by a full-matrix least-squares procedure to R 0.052
for 663 observed reflections (Mo Kα automatic
diffractometry). The structure contains a dimethyl bridge, the average bridging
bond distances being 2.58(3) Ǻ for Y-C and 2.10(2) Ǻ for Al-C, and
the Y-Al separation is 3.056(6) Ǻ.
Reactions of titanium(IV) chloride with formic acid
Authors: Paul RC , Kumar RC , Baidya OB , Kapoor R
Published: September 2010

Titanium(IV) chloride
reacts with formic acid to give the disubstituted product, Cl2Ti(OOCH)2,
at low temperatures and the hydrolysed product (OH)2Ti(OOCH)2
at higher temperatures. These compounds have been characterized by elementary
analysis, infrared and thermal measurements. The possibility of these
solvolysed products acting as Lewis acids has also been explored.
Purine analogues as amplifiers of phleomycin. III. Some 2-alkylthio derivatives of imidazole, benzimidazole, benzoxazole and benzothiazole
Authors: Brown DJ , Dunlap WC , Grigg GW , Danckwerts L
Published: September 2010

Some 2-methylthio and
2-carbamoylalkylthio derivatives of 1-methylimidazole, benzimidazole, benzoxazole,
benzothiazole and 6-dimethylaminobenzothiazole have been synthesized by
alkylation of the corresponding thiones. Their in vitro activities, as amplifiers
of phleomycin against Escherichia coli, varied from slight to high but none was
outstanding. 2-(Benzothiazol-2'-ylthio)acetamide (2j)showed maximal activity at
c. 0.04 mM with progressive decreases at both higher
and lower concentrations.
Preparation of 5,5-Bis(2-deuterophenyl)hydantoin
Authors: Coombe RG , Poulton DB
Published: September 2010

Preparation of the
anticonvulsant 5,5-diphenylhydantoin specifically labelled with deuterium in a
metabolically stable position is described.
Preparation and characterization of some ternary complexes of copper(II) with o-phenanthroline and oxygen donor ligands
Authors: Kwik WL , Ang KP
Published: September 2010

A series of eight ternary
complexes, viz. [Cu(phen)(acac)] Cl
and Cu(phen)L(H2O)n(phen = o-phenanthroline; L = a
bidentate oxygen donor ligand; n = 0, 1 or 2), have been prepared and
characterized by microanalysis, infrared spectral and electronic spectral
measurements. The results indicate that the Cu(phen)2+ species has a
great affinity for oxygen donor ligands resulting in chelate rings of varying
sizes. Infrared spectral data indicate that the Cu-O bond weakens as the oxygen
donor chelate ring increases in size; the Cu-N bond appears to be less
sensitive to ring size. Tentative assignments for the electronic absorption
bands have also been made.
Electron and nuclear spin relaxation in paramagnetic transition-metal complexes with S = 1. The effects of a non-zero average zero-field splitting on the spin energy levels
Authors: Pegg DT , Doddrell DM
Published: September 2010

The effects of a non-zero
average zero-field splitting on electron spin relaxation in paramagnetic (S =
1) complexes is treated theoretically. The spin-lattice interaction is
postulated to be a simple scalar P(t). S process with correlation time Ti.
This process is assumed not to modulate the zero-field splitting which,
however, is modulated by the molecular tumbling. The frequency dependence of
the nuclear relaxation time (Tl) now depends on the magnitude of the
zero-field splitting constant (D), and, for large values of D, the value of T1
is independent of the applied field strength.
Preparation of the hexadentate ligand ( - )546-2,2'-[(1,1'-Binaphthalene-2,2' diyl)bis{methylenethio(ethane-1,2-diyl)nitrilomethylidyne}]bisphenol and a study of the stereochemistry of its cobalt(III) complex
Authors: Gahan LR , O'Conner MJ
Published: September 2010

The hexadentate ligand (-)546-2,2'-[(1,1'-binaphthalene-2,2'-
diyl)bis{methylenethio(ethane-1,2-diyl)-nitrilomethylidyne}]bisphenol
(the doubly deprotonated form is abbreviated as nmep)
has been prepared in the S-absolute configuration with respect to the binaphthyl
group by reactions on 1,1'-binaphthyl-2,2'-dicarboxylic acid of known absolute
configuration S that do not involve the asymmetric binaphthyl moiety. ��� The cobalt(III) complex (+)546-[Co(-)546(nmep)] ClO4 has been prepared by metal exchange
of cobalt(II) ions on the zinc(II) complex followed by air oxidation. The
preparative method yielded only one isomer. The complex is a uni-univalent electrolyte in nitromethane. ��� Measurement of 13C spectra in
dimethyl[D6] sulfoxide, circular dichroism and ultraviolet/visible
spectra in dimethylformamide and Dreiding molecular
models indicate that the complex has the α- geometrical structure, and
that the optically active binaphthyl group directs the absolute configuration
at the dissymmetric cobalt centre to be Λ (IUPAC) or Δ (C2).
The thiomethyl sulfur atoms have the S-absolute configuration.
The constitution of N-substituted 2-(Iminomethyl)benzenethiols (o-Mercaptobenzaldimines)
Authors: Corrigan MF , Rae ID , West BO
Published: September 2010

The constitution of a
number of 2-(iminomethyl)benzenethiols and 2-
(iminomethyl)-4-nitrobenzene-thiols has been studied by 1H N.M.R.
spectroscopy. A zwitterionic imminium structure is suggested for all the compounds
studied except for the 4'-methoxyphenylimine derivative which exists in the
thiol form.
Acid-catalysed rearrangements in the furan series. III. The reaction of 2-Acetoxy-5-nitro-2,5-dihydro-2-furylmethylene diacetate with methanolic hydrogen chloride
Authors: Greene BB , Lewis KG
Published: September 2010

Vigorous treatment of
2-acetoxy-5-nitro-2,5-dihydro-2-furylmethylene diacetate with hydrogen chloride
in methanol has been shown to give methyl 5,5-dimethoxy-4-oxopentanoate rather
than methyl 5,5-dimethoxy-2-oxopent-3-enoate as suggested by Srogl and Peterek. In addition several other
previously unreported products of the reaction have been isolated and their
structures assigned. When the acid treatment is performed under mild
conditions, the main product of the reaction is cis-2,5-dimethoxy-2,5-dihydrofurfuraldehyde
dimethyl acetal which under more vigorous acid conditions is converted into a
complex mixture similar to that obtained by vigorous acid treatment of the
parent acetoxy nitro compound.
The crystal structures of the Hexakis(pyridine 1-oxide) complexes of copper(II), cobalt(II) and iron(II) perchlorates
Authors: Taylor D
Published: September 2010

The crystal structures of
the isomorphous complexes [M(pyridine 1-oxide)6] (ClO4)2
M = Cu (1), Co (2) and Fe (3), have been determined from X-ray diffractometer
data collected at 293 K. The complexes crystallize in the rhombohedral space
group R3 with Z = 1; cell constants for (1): a 9.605(1)Ǻ, α 81.10(1)°;
for (2): a 9.619(1)Ǻ, α 81.19(1)°; for (3): a 9.640(1)Ǻ, α
81.06(1)°. The structures were solved by Fourier techniques and refined by
block-diagonal least squares to convergence at R, R': (1) 0.037, 0.039 for 1009
reflections; (2) 0.030, 0.038 for 812 reflections; (3) 0.032, 0.041 for 780
reflections with I ≥ 3σ(I). The cations have exact S6
symmetry with the MO6 moiety having almost exact Oh
symmetry, which implies for (1) a lack of a static Jahn-Teller
distortion. The M-O distances increase (1) 2.076(2), (2) 2.090(1), (3)
2.112(2)Ǻ in the order expected. The geometries of the pyridine 1-oxide
ligand and the perchlorate ion are consistent over the three determinations and
are normal.
An assessment of oxime-oximato hydrogen bonding: A structural and thermodynamic study of copper(II) complexes
Authors: Daniel EA , March FC , Powell HKJ , Robinson WT , Russell JM
Published: September 2010

Copper(II) complexes formed
by the diamine dioxime ligand 4,4,9,9- tetramethyl-5,8-diazadodecane-2,11-dione
dioxime (H2dddo) and its O-methyl ether (Hddmo)
and bis-O-methyl ether (dddm) have been studied. The
log K (potentiometric) and ΔH (calorimetric) values are reported for
formation of the four-coordinate complexes [Cu(Hddmo)]2+
and [Cu(dddm)]2+ and for the deprotonation
of [Cu(Hddmo)]2+ to give [Cu(ddmo)]+ at 25°C, I = 0.1 M NaCl.
(log K = 12.11 � 0.04, 9.10�0.02 and -6.76�0.09; ΔH= -43�2, -17.9�0.4 and +21.9�0.9
kJ mol-1 respectively.) Comparison with data for [Cu(H2dddo)]2+
and [Cu(Hdddo)]+ affords information about
the relative contributions of (i) oxime deprotonation
(c. 105.6), and (ii) oxime oximato hydrogen bonding (c. 103.5),
to the stability of these (non-conjugated) dioxime complexes. The formation of
intramolecular (oxime-oximato) hydrogen bonds is favoured by a positive ΔS;
intermolecular bonds (oximato-solvent) give rise to a negative ΔS. ��� A single-crystal X-ray molecular structure
determination is reported for the complex Cu(dddm)-(ClO4)2.
In the solid state the complex cation is square pyramidal with one perchlorate
ion weakly coordinated in the apical position and the four nitrogen donor atoms
forming a distorted square plane about the copper atom. Steric effects
associated with O-methyl substitution are assessed. Steric hindrance between
adjacent =NOR groups does not increase measurably when =NOH is replaced by =NOMe.
Crystal structures of 2-Hydroxyimino-1-phenylethan-1-one and ethyl 3-Oxo-2-sodiooxyiminobutanoate
Authors: Raston CL , Sharma RP , Skelton BW , White AH
Published: September 2010

The crystal structures of
the title compounds, PhCOCH=NOH (5) and Na+[MeCOC(=NO-)CO2Et],-2H2O
(10), have been determined by single-crystal X-ray diffraction at 295 K and
refined by least squares to R 0.051, 0.062 (815, 1199 'observed' reflections)
respectively. Crystals of (5) are monoclinic, P21/n, a 14.177(6), b
5.075(4), c 11.049(6) Ǻ, β 112.89(3)°, Z4. Crystals of (10) are
tetragonal, 141/a, a 19.41(1), c 10.643(5)Ǻ Z 16. In (5),
within the C=NOH group, C-N is 1.263(4) and N-O is 1.375(4)Ǻ; in (10) C-N
is 1.318(6) and N-O is 1.321(5)Ǻ. In (10), the (presumably) negative C=NO-
group does not coordinate the sodium ion; the latter is bridged by water
molecules, occupying four close coordination positions
[2.405(4)-2.552(4)Ǻ] in an interesting bridged polymeric array while the
remaining two coordination positions are occupied by two ligand C=O groups
[2.363(4), 2.393(4) Ǻ], the ligands also bridging sodium ions.
Spectral studies of the isomeric tetradentate Schiff bases derived from 1,1,1-Trifluoro-5,5-dimethylhexane-2,4-dione and Ethane-1,2-diamine
Authors: Dilli S , Patsalides E
Published: September 2010

Two of the three possible
isomeric tetradentate Schiff bases obtained from the 2 : 1 condensation of
1,1,1-trifluoro-5,5-dimethylhexane-2,4-dine and ethane-1,2-diamine have been
obtained and their structures assigned from infrared, N.M.R. (1H and
19F) and mass spectroscopy.
The synthesis of some t-butyloctahydronaphthalenes
Authors: Gream GE , Laffer MH , Serelis AK
Published: September 2010

The unambiguous syntheses
of eleven t-butyloctahydronaphthalenes are described. Those obtained in pure
states are 2-t-butyl-1,2,3,4,5,6,7,8- octahydronaphthalene (1),
7α-t-butyl-1,2,3,4,4aα,5,6,7- octahydronaphthalene (2),
2α-t-butyl-1,2,3,4,4aα,5,6,7- octahydronaphthalene (4),
2α-t-butyl-1,2,3,4,-4aβ,5,6,7- octahydronaphthalene (5),
3α-t-butyl-1,2,3,4,4aβ,5,6,7- octahydronaphthalene (14), 7-t-butyl-1,2,3,4,4aβ,5,6,8aβ-
octahydronaphthalene (27), 6-t-butyl-1,2,3,4,4aβ,5,8,8aβ-octahydronaph-
thalene (28) and 2α-t-butyl-1,2,3,4,4aβ,5,6,8aβ-octahydronaphthalene
(57). 7α-t-Butyl-1,2,3,4,4aβ,-5,6,7-octahydronaphthalene (3) was
obtained in a state of 95% purity while 6α-t-butyl-1,2,3,4,4aβ,-5,6,7-
octahydronaphthalene (15) and 6α-t-butyl-1,2,3,4,4aβ,5,6,8aβ-octahydronaphthalene
(33) were obtained as inseparable mixtures with (14) and (28), respectively.
The 9-decalyl and related cations. IV. Generation of cis- and trans-2-t-Butyl-9-decalyl cations through σ-routes by acetolysis
Authors: Gream GE , Laffer MH , Serelis AK
Published: September 2010

The synthesis and
solvolytic behaviour (in buffered acetic acid) of cis- and
trans-9-t-butylspiro[4,5]-dec-6-yl p-toluenesulfonate (5) and (6) are
described. The two compounds solvolyse with anchimeric assistance and undergo
ring expansion with complete stereospecificity; the cis- and trans-esters yield
trans- and cis-2-t-butyl-9-decalyl cation (8) and (7), respectively. To account
for the stereospecificity, it is proposed that (6) must solvolyse through a
boat conformation of the six-membered ring. Ring contraction (c. 8%), with the
formation of the 1-(3'-t-butylcyclopentyl)cyclopentyl cation (presumably trans
(36)), also takes place in the acetolysis of (6). ��� The possible role of ion-pairs in the
reactions of (5) and (6) is examined. It is concluded that the anion in an
ion-pair might be involved in olefin formation only when it (the anion) is
ideally located for proton abstraction in the initially formed ion-pair (or
that formed by conformational interconversion of the cationic moiety).
The dependence of the free energy of micelle formation on aggregation number and critical micelle concentration
Authors: Hamann SD
Published: September 2010

It is shown that a formula
proposed recently, to express the way in which the free energy of formation of
molecular micelles depends upon the aggregation number of the micelles, is
incorrect. The correct relationship is derived.
Crystal structure of (E)-5,7-Di-t-butyl-3-(3',5'-di-t-butyl-5'-methoxy-2',5'-dihydrofuran-2'-ylidene)benzofuran-2(3H)-one
Authors: Becker H , Hall SRRCL , White AH
Published: September 2010

The crystal structure
(E)-5,7-di-t-butyl-3-(3',5'-di-t-butyl-5'- methoxy-2',5'-dihydrofuran-2'-ylidene)-benzofuran-2(3H)-one,
C29H42O4, has been determined by
single-crystal X-ray diffraction methods at 295 K from counter data and refined
by least squares to a residual of 0.086 for 1488 'observed' reflections.
Crystals are monoclinic, P21/a, a 12.136(6), b 10.055(4), c
23.011(11) Ǻ, β 96.87(4)°, Z4.
Crystal structure of ammonium cis-Tetraamminedisulfitocobaltate(III) trihydrate (a redetermination)
Authors: Raston CL , White AH , Yandell JK
Published: September 2010

The crystal structure of
the title compound, NH4 [Co(NH3)4(SO3)2],3H2O,
has been redetermined using diffractometer data at 295 K and refined by
full-matrix least squares to a residual of 0.056 for 2068 'observed'
reflections. Crystals are orthorhombic, P212121,
a 10.978(4), b 17.552(7), c 6.828(3)Ǻ, Z 4. The redetermined structure
provides accurate structural data for the cobalt environment; as well, it
locates all hydrogen atoms and defines cations and water molecules un-
ambiguously. Co-S are 2.224(2), 2.221(2) Ǻ. Co-N (trans to S) (1.993(6),
2.023(6) Ǻ) are longer than the mutually trans Co-N (1.970(7), 1.977(6)
Ǻ); the difference in the former is a consequence of lattice hydrogen
bonding.
A 15N and 13C N.M.R. study of electron distribution in Di- and Tri-azapentadienium salts
Authors: Jones AJ , McNab H , Hanisch P
Published: September 2010

The 15N and 13C
chemical shifts of eight vinamidinium and azavinamidinium cations have been
determined at the natural-abundance level by means of Fourier methods. Both 15N
and 13C chemical shifts reflect the electron- density distribution
in the pentadienium chain, especially in the aryl derivatives in which
conjugative stabilization through electron withdrawal by the substituent phenyl
group is exhibited.
Synthesis of the lichen depsides, olivetoric acid, confluentic acid and 4-O-methylolivetoric acid
Authors: Elix JA , Ferguson BA
Published: September 2010

Total syntheses of the
lichen depsides olivetoric acid, confluentic acid and 4-O-methylolivetoric acid
are reported.
Reductive methylation of 2-naphthoic acids
Authors: Slobbe J
Published: September 2010

The successive action of lithium
(2.5 equiv.) and methyl iodide on 2- naphthoic acids in ammonia gives
2-methyl-1,2-dihydro-2-naphthoic acids in fair yield.
Substituent and solvent effects on the reaction between 2,6-Di-t-butyl-α-(3,5-di-t-butyl-4-oxocyclohexa-2,5-dien-1-ylidene)-p-tolyloxyl (galvinoxyl) and phenols
Authors: Nishimura N , Okahashi K , Yukutomi T , Fujiwara A , Kubo S
Published: September 2010

Rate constants and
associated activation parameters for the reaction of galvinoxyl with
substituted phenols were obtained in carbon tetrachloride and in cyclohexane-dioxan
binary mixtures. Substantial isotope effects were observed for O-deuterated
phenols. The rate constants are correlated with σ+ values. These findings
are discussed by considering the polar contribution of substituents to the
stabilization of the transition states. In the mixed solvents, the kinetic
behaviour is well expressed by the equations which are based on the theory of
Kondo and Tokura.
1,3,6,8,11,13-Hexachloro-4,10-dihydroxydinaphtho[2,1-b:1 ',2'-d]furan-5,9-dione. A polychloro quinone from green soils
Authors: Cameron DW , Sidell MD
Published: September 2010

A polychloro pigment, C20H4C16O5,
isolated from certain green soils, has been assigned the title structure (3).
It is the first natural example of this ring system. It has structural
affinities with known constituents of wood rotting fungi.
Nucleophilic alkenes. IV. Addition of 1,1-dialkoxyethenes to 1,4-benzoquinones. The 1 : 1-process
Authors: Cameron DW , Crossley MJ
Published: September 2010

Reaction of
1,4-benzoquinones with 1,1-dialkoxyethenes in dimethyl sulfoxide gave high
yields of 1,4-naphthoquinones by 1 : 2-addition. Hexahydro- and
dihydro-naphthoquinone intermediates were isolated. In boiling hydrocarbon
solvents reaction with 1,4-benzoquinones led chiefly to 1 : 1- addition.
2,2-Dialkoxy-2,3-dihydrobenzofurans were obtained. These stoichiometric adducts
are evidently the source of 2-ethoxyfuran, lactone and quinonyl acetic acid
derivatives observed in previous work.
Structure of aqueous solutions. A librational band study of hydration in solutions containing dipositive and tripositive metal ions
Authors: James DW , Armishaw RF , Frost RL
Published: September 2010

The librational band of
water has been studied in aqueous solutions of the nitrates and chlorides of MgII,
CaII, SrII, CoII, NiII, CuII,
ZnII, PbII, LaIII, AlIII, CrIII,
ThIV. The contribution due to coordinated water has been separated
from the remainder of the band and the band frequency is found to be
proportional to the hydrolysis constant (*K1) for the reaction ��������������� [M(OH2)6]n+
→ [M(OH2)5OH](n-1)++H+
The metal-oxygen stretching
frequency has also been identified and is found to show a similar relationship
to *K1. Changes noted between solutions containing nitrate and
chloride anionic species are discussed in terms of solution structure.
The interaction of DNA with aminoacridines and aminobenzacridines
Authors: Ellerton NF , Jordan DO
Published: September 2010

The binding curves and
thermal denaturation of several DNA- aminoacridine and DNA-amino-benzacridine
complexes at two ionic strengths are reported. An increase in viscosity and a
decrease in sedimentation velocity were found for these DNA-dye systems. Free
energy calculations based on the intercalation model have been performed. The
values so obtained for ΔG are discussed and correlated with the data found
in the above experiments.
An N.M.R. investigation of the metal-ligand bonding in some transition metal complexes of Bicyclo[3,3,1]nona-2,6-diene
Authors: Bishop R
Published: September 2010

The structure of the
bicyclo[3,3,1]nona-2,6-diene complexes with formulae (diene)PdCl2,
(diene)PtCl2, and [(diene)RhCl]2
has been shown, by use of 1H and 13C N.M.R. spectroscopy
and deuterium labelling, to involve two equivalent metal-olefin bonds preferentially
bonded to carbon atoms 2 and 6. Two crystalline forms (α, β) of the
palladium complex were obtained. These were completely inter-convertible in
either direction from solution, with the a-form being converted into the P-form
(with concurrent halogen exchange) under i.r. KBr disc conditions.
Studies with Bicyclo[2,2,2]octenes. VIII. Synthesis of the Tricyclo[5,2,2,01,5]-undecane skeleton related to eremolactone
Authors: Feutrill GI , Mirrington RN
Published: September 2010

Synthesis of
8,8-dimethyltricyclo[5,2,2,01,5]undecane-4,9-dione (3) has afforded
the novel ring system which forms the central nucleus of the diterpene
eremolactone.
Nitrones and oxaziridines. XX. Intramolecular nitrone 1,3-dipolar cycloaddition by substituent interaction: Synthesis and reduction of some tetrahydropyrroloisoxazoles
Authors: Black DSC , Crozier RF , Rae ID
Published: September 2010

The reactions of
C-benzoylnitrones with allylamine afford tetrahydro-5H-pyrrolo[3,4-c]isoxazoles
resulting from imine formation and intramolecular 1,3-dipolar cycloadditions.
Cycloaddition reactions of the same nitrones with 2-vinylpyridine and
N-phenylallylamine afford 5-substituted isoxazolidines in the normal way.
Reduction of the imine bond in the tetrahydropyrroloisoxazoles can be achieved
by catalytic hydrogenation or sodium borohydride, and, in the case of an
N-phenyl derivative, N-O bond cleavage also occurs.
Alkaloids of Daphnandra apatela
Authors: Bick IRC , Sotheeswaran S
Published: September 2010

The rare alkaloid telobine
(3) has been isolated from the bark of the new Daphnandra sp., D. apatela Schodde, together with
five new alkaloids. The structures of three of these, apateline (1), 1,2-dehydroapateline (6) and 1,2-dehydrotelobine (5), have been
determined.
19F nuclear magnetic resonance studies of the interaction of inhibitors with chymotrypsin. Ring-fluorinated derivatives of N-trifluoroacetylphenylalanine
Authors: Tsavalos M , Nicholson BC , Spotswood TM
Published: September 2010

The complexes formed
between chymotrypsin and the doubly fluorine- labelled inhibitors, o-, m- and
p-fluoro-N-trifluoroacetyl-D- phenylalanine and
2,4-difluoro-N-trifluoroacetyl-D-phenylalanine, have been characterized by 19F
N.M.R. spectroscopy and binding parameters, ΔB and KI,
have been derived. The results confirm the importance of the amido binding site
in orienting aromatic amino acids at the active site of chymotrypsin. Changes
in ΔB, the change in chemical shift of the enzyme-bound
inhibitor, are shown to be a very sensitive probe of enzyme-inhibitor
interactions.
Direct conversion of α-halo acids into α-halo amides by reaction with 2-phenylazirine
Authors: Black DSC , Doyle JE
Published: September 2010

Chloro-, bromo-, iodo- and
cyano-acetic acids undergo reaction with 2- phenylazirine
to afford the highly crystalline 2-chloro-, 2-bromo-, 2- iodo- and
2-cyano-N-phenacylacetamides respectively.
Demethylation of a steroid methyl ether with concomitant ring expansion
Authors: Blair IA , Frith RG , Phillipou G , Seaborn CJ
Published: September 2010

Demethylation of
pregn-5-ene-3β,20β-diol dimethyl ether with ferric chloride/acetic
anhydride is shown to form the ring-expanded steroid
17α-methyl-D-homoandrost-5-ene-3β,17aβ-diol (1) in 75% isolated
yield.
Thermodynamics of metal-ligand bond formation. XXXI. Reaction of Bis(diphenyldithiophosphinato)nickel(II) with heterocyclic bases
Authors: Anh VTP , Graddon DP , Ng VAK
Published: September 2010

The low-spin, planar
complex (Ph2PS2),Ni reacts with heterocyclic bases to
form (Ph2PS2)2NiB and (Ph2PS2)2NiB2
(B = pyridine or 4-methylpyridine). Average thermodynamic data for adduct formation
in chlorobenzene at 30°C are: with pyridine K1 500, K2 251.
mol-1, ΔH1� -34, ΔH2� -44 kJ mol-1; with
4-methylpyridine K1 1000, K2 50, ΔH1°
-35, ΔH2°-41. With 2- methyl-pyridine only the 1 : 1 adduct is
formed, with K 13, ΔH° -34. In these systems the five-coordinate 1 : 1
adducts are unusually stable and are shown to have the high-spin configuration.
Specificity in the adsorption of dyes on oxide surfaces
Authors: Chicco B , Heijkoop T
Published: September 2010

Total adsorption and
chemisorption isotherms of the acid dye fluorescein and the basic dye rhodamine
B from ethanolic solution have been determined for magnesium oxide, α-alumina,
zinc oxide and kieselguhr. Molar ratios of the two dyes adsorbed on each of the
oxides show a variation of more than two orders of magnitude for both
physisorption and chemisorption, which demonstrates that the physical bond can
be highly specific in this type of system. ��� The effects of varying the liquid/solid
ratio and of using different solvents have been studied, and it is suggested
that significant improvements in the estimation of specific surface area by dye
adsorption can be effected by appropriate selection of both dye and
liquid/solid ratio.
Crystal structure of Bis(O-ethylxanthato)bis(quinolin-8-olato)tin(IV)
Authors: Raston CL , White AH , Winter G
Published: September 2010

The crystal structure of
the title compound, [Sn(S2COEt)2(C9H6NO)2],
has been determined by single-crystal X-ray diffraction at 298 K and refined by
least squares to a residual of 0.049 for 1771 ?observed? reflections. Crystals
are monoclinic, P21/n, a 12.21(1), b 24.33(1), c 9.159(7) Ǻ,
β 102.12(6)°, Z 4. The environment of the tin atom is six- coordinate: the
two coordinating sulfur atoms of the monodentate xanthate ligands lie cis in
the coordination sphere [Sn-S, 2.484(4), 2.510(4)
Ǻ], and one in turn trans to the two oxine nitrogen atoms [Sn- N, 2.260(8), 2.237(10) Ǻ]. The remaining
positions, trans to each other, are occupied by the oxine oxygen atoms [Sn-O, 2.047(7), 2.065(8) Ǻ]. O-Sn-O
is 157.0(3)°. The overall point symmetry of the molecule is a good approximation
to 2.
C-Glycosylflavonoids. II. The synthesis of 7,4'-Di-O-methylpuerarin (8-C-β-D-Glucopyranosyl-7,4'-dimethoxyisoflavone)
Authors: Eade RA , Mcdonald FJ , Pham H
Published: September 2010

The product of reaction of
2'-acetoxy-4,4'-dimethoxy-3'-(tetraacetyl-β-D-glucopyranosyl)chalcone (4)
with thallium(III) nitrate in methanol/trimethyl orthoformate solution gave,
after acid hydrolysis, a high yield of 7,4'-di-O-methylpuerarin (2). The dimethyl
acetal (6) and the enol ether (7) have been isolated
from the reaction of the chalcone (4) with thallium(III) nitrate in methanol.
Both the acetal (6) and ether (7) gave 7,4'-di-O-methylpuerarin on reaction
with acid or base.
Bonding and nuclear quadrupole coupling in linear pentaiodide ions
Authors: Bowmaker GA
Published: September 2010

The charge distribution in
linear pentaiodide ions of D∞h symmetry has been calculated by
using a five-centre six-electron bonding scheme involving the iodine 5pσ
orbitals. This is an extension of the three- centre four-electron scheme which
accounts well for the values of the nuclear quadrupole coupling constants for
trihalide ion and amine- halogen complexes. It has recently been shown that the
amylose-iodine complex may contain linear I5- ions, and
it is shown in the present work that the five-centre six-electron bonding
scheme accounts well for the values of the quadrupole coupling constants
obtained from the iodine- 129 Mossbauer spectrum of this complex.
Environment of solubilized molecules in bile salt micelles
Authors: Fisher LR , Oakenfull DG
Published: September 2010

Bile salt micelles, and
mixed bile salt-phospholipid micelles, solubilize cholesterol and dietary lipids. As a first step
in a study of the mechanism of solubilization by bile
salt micelles, we have studied the solubilization of
two fluorescence probe molecules and an electron spin resonance probe molecule.
One fluorescence probe, 1-methylanthracene, is free to rotate in the molecular
plane when solubilized. The other probe molecules, N-phenylnaphthalen-1-amine and 4-(11-carboxy-1-hexylundec-1-yl)-
2,2,6,6-tetramethylpiperidin-1-yloxy, are greatly restricted in mobility when
solubilized. The 1-methylanthracene molecule is planar, and is small enough to
fit into the hydrophobic region of a bile salt micelle without protruding. The
other probe molecules used do not fit these criteria. We suggest that small
planar molecules in general may be free to rotate (about an axis perpendicular
to the plane) in bile salt micelles. Thus solubilization
of planar molecules would be entropically favoured. In particular, cholesterol is a planar molecule
known to be highly solubilized by bile salt micelles. The cholesterol molecule
meets the above criteria, and thus we suggest that its solubilization
is entropically favoured
over non-planar molecules.
Vinylindenes and Some Heteroanalogues in the Diels-Alder Reaction. VI. Vinylbenzo[b]thiophens and Ethenetetracarbonitrile
Authors: Cherry WH , Craig JT , Porter QN
Published: September 2010

3-Vinylbenzo[b]thiophen and
three simple homologues are shown to give normal Diels-Alder
adducts with ethenetetracarbonitrile, whereas the
3-methyl-2-vinyl- and 2-methyl-3-prop-1'-enyl derivatives give cyclobutanes. 2-Methyl-3-vinylbenzo[b]thiophen and ethenetetracarbonitrile
give an adduct resulting from reaction of a tautomeric form of the diene, but a
naphthalene analogue and a phenanthrene analogue of this substituted
benzothiophen give normal adducts.
The Crystal and Molecular Structure of Bis-[μ-2-(p-nitrophenyliminomethyl)phenolato-N,O]-bis(ethanol)bis(nitrato-O,O')dinickel(II), [Ni(slno)NO3(C2H5OH)]2, a Binuclear Ferromagnetic Salicylaldimine Derivative of Nickel Nitrate
Authors: Butcher RJ , Sinn E
Published: September 2010

The crystal and molecular
structure of the complex bis-[μ-2-(p-nitrophenyliminomethyl)phenolato-
N,O]-bis(ethanol)bis(nitrato-O,O')dinickel(11) and its magnetic
properties are reported. Crystal data: space group PI, Z 1, a 8.882(2), b 9.332(3), c 12.533(4) �,
α 94.40(2),B 109.99(2), γ 111.61(2)�, U 883 �3, R 2.8%, Rw 3.3% for 2154
reflections. The compound is prepared from the reaction of bis(N-p-nitrophenylsalicylaldimine)nickel(II)
with nickel nitrate in hot triethoxymethane, and on cooling the solution deposited
pale green transparent crystals. The structure contains neutral dimeric units
with bridging through the phenolic oxygen atoms and has distorted octahedral
geometry about each crystallographically identical nickel atom. The six donor
atoms are made up of two oxygen atoms from the bidentate nitrate, oxygen from
ethanol, nitrogen from the imine group and two bridging phenolic oxygen atoms.
The Ni2O2 group is strictly planar possessing a
crystallographic centre of symmetry. The angles subtended at the bridging
oxygen atoms indicate a tetrahedral geometry and it is demonstrated that this
is important in explaining the ferromagnetic intradimer interaction. The
presence of hydrogen bonding between the ethanol hydrogen and the nitrate group
of an adjacent molecule appears to be an important stabilizing factor in
determining the structure and provides a possible pathway for the
antiferromagnetic interdimer exchange interaction.