Volume 32, Issue 10

(OC) 5 M-GeX 2 · THF and (OC) 5 M-SnX 2 · THF are formed by the reactions of disodium decacarbonyl dimetallates of 6 b metals with the tetrahalides GeX 4 and SnX 4 : Na 2 [(OC) 5 M -I -M -I (CO) 5 ] + EX 4 [xxx](OC) 5 M -II -EX 2 · THF [xxx] Na[M°(CO) 5 X] (M = Cr, Mo, W; E = Ge, Sn; X = Cl, Br, I).

The complexes (OC) 5 M-InX · THF are formed by the reactions of the disodium decacarbonyl dimetallates of VI b metals with InX 3 : [xxx] The structure of Cr(CO) 5 InBr · THF, which crystallizes in the space group Pbca-D 15 2h has been determined by X-ray diffraction.

Ph 3 Sn(OC) 4 Fe-Fe(CO) 4 SnPh 3 and ClPh 2 Sn(OC) 4 Fe-Fe(CO) 4 SnPh 2 Cl are formed by the reactions of dipotassium octacarbonyl diferrate(-I) with Ph 3 SnCl and Ph 2 SnCl 2 : K 2 [(OC) 4 Fe-Fe(CO) 4 ] + 2 Ph 3 SnCl → Ph 3 Sn(OC) 4 Fe-Fe(CO) 4 SnPh 3 + 2 KCl K 2 [(OC) 4 Fe-Fe(CO) 4 ] + 2 Ph 2 SnCl 2 → ClPh 2 Sn(OC) 4 Fe-Fe(CO) 4 SnPh 2 Cl + 2 KCl.

The new complexes (OC) 5 MSC(X)Y (8-5) are obtained by reaction of (OC) 5 MTHF (1) [M = Cr (a), Mo (b), W (c)] with different thiocarbonate, thiourea and thiourethane ligands S = C(X)Y (2a-h). Structure and bonding conditions are discussed on the basis of their IR and 13 C NMR spectra. From the spectroscopic data the ligands 2a-h can be arranged in a row with increasing π-acceptor properties.

Single crystals of the compounds Lu 2 Cu 2 O 5 (A) and Sc 2 Cu 2 O 5 (B) were prepared by melting the oxide mixtures (2 CuO : 1 Lu 2 O 3 , 2 CuO : 1 Sc 2 O 3 ) in a KF-flux. The crystal structures were investigated by single crystal X-ray data (Space group : C 2V 9 –P2 1 nb, lattice constants (A): α = 1235.0, b = 1069.8, c = 340.5pm, (B): α = 1204.1, b = 1045.2, c = 322.0 pm). (A) and (B) are isotypic with Ho 2 Cu 2 O 5 and differ from the Cu 2 In 2 O 5 type in respect of the Cu 2+ -coordination.

V 1-x Fe x O 2-x F x samples (0 ≤ x ≦ 0.20) have been prepared by solid state reaction in sealed platinum tubes. The temperature-composition phase diagram with 0 < x ≦ 0.04 is found to contain four phases which were determined by X-ray diffraction and 57 Fe-Mössbauer measurements. At small (Fe 3+ , F - ) concentrations (x < 0.005) only one Fe-site is seen in the low-temperature M 1 phase and one transition from the insulator to metallic phase. For 0.005 ≦ x ≦ 0.008 at temperatures just below the metal-insulator transition a second monoclinic phase M 2 is stable in which two Fe-sites are resolved by their electric field gradients and their isomer shifts. These two sites are identified as the Fe atoms on the paired V-V chains and the equispaced V-V chains in the C2/m structure of MAREZIO et al. At higher Fe 3+ , F - concentrations (x > 0.008) the existence of the intermediate phases M 2 and M 3 , between M 1 and the rutile phase, has been confirmed.

NaBeAs and NaBeSb crystallize in a modified Ni 2 In-type-structure, space group P 6 3 /mmc–D 6h 4 . Preparation and structure determination with powder and single crystal data are described. The bonds and the structure are discussed in comparison with corresponding compounds of the formula AMe II X. The lattice constants are: NaBeAs: α = 3,820(5), c = 8,948(9), c/α = 2,34; NaBeSb: α = 4,144(5), c = 9,320(9), c/α = 2,25.

The photoreaction of the indenyl complexes C 9 H 7 M(CO) 3 CH 3 (M = Mo, W) with alkynes (L) in solution leads to 1:1 adducts, which are found to be metallocyclic alkenylketone compounds C 9 H 7 M(CO) 2 (L-COCH 3 ). UV irradiation of C 9 H 7 W(CO) 3 CH 3 in the presence of either acetylene or methylacetylene also gives substituted derivatives C 9 H 7 W(CO)(L)CH 3 in low yields. For these compounds, the intramolecular mobility of the π-bonded alkyne ligand can be demonstrated by temperature-dependent 1 H NMR spectroscopy.

Bimetallic tungsten-germanium and tungsten-tin compounds (e.g. π-C 5 H 5 (CO) 3 W-MR 3 ; M=Ge, Sn; R=CH 3 , C 6 H 5 ) upon activation with Cl 2 Al-i-C 4 H 9 /O 2 (2:1) give highly active catalytic systems for the homogeneous metathesis of linear olefins with internal double bonds (2-hexene, 3-heptene, 4-octene). The activation procedure has a decisive influence on the reaction velocity and the distribution of products. Starting the reaction by addition of oxygen to the mixture of the other compounds, the metathesis leads selectively and slowly to the primary metathesis products. On the other hand the metathesis takes place rapidly if the olefin is added to the preformed catalytic system. In this case metathesis is accompanied by strong double bond isomerisation and yields broad range olefin mixtures.

The preparation, for the first time, of ether and pyridine compounds of mixed complex halo acids of indium(III) with thiocyanate is described. The study of the chemical and physical properties of these acids and the UV and IR spectra of the pyridine compounds are also reported and discussed.

The mass spectral fragmentation patterns of trans-1,2-di-(3-pyridyl)ethylene and trans- 1,2-di-(4-pyridyl)ethylene obtained on electron impact have been elucidated. They are more complex than the disintegration pathway observed with trans-1,2-di-(2-pyridyl)-ethylene.

The base peaks in the mass spectra of Ν,N′-diphenylformamidine, N,N′-di-(4-chlorophenyl)formamidine and N,N′-di-(3-chlorophenyl)formamidine are due to the molecular ions of aniline, 4-chloroaniline and 3-chloroaniline respectively. The species responsible for the base peaks are thought to be formed by rupture of the CH-NH bond with concomitant hydrogen migration.

Models of alkylbenzenes were treated by the HMO and SCF—MO methods and excellent linear correlations were found between the experimental ionization potentials, E I , and the energies of the highest occupied π-molecular orbitals calculated by the above-mentioned methods. A similar linear correlation was obtained for a group of methylpyridines. Also, the experimental ionization potentials of methylpyridines and alkylthiophenes have been linearly correlated with the sum of TAFT'S inductive substituent constants, Σσ I of the alkyl groups.

Substituted methylenetriphenylarsenanes react with 2,7-disubstituted fluorenones to give exocyclic olefins, 9-arylidene-2,7-disubstituted fluorenes and/or exoxides, 2,7-disubstituted fluorene-9-spiro oxiranes. Spectral data for the resulting products were also incorporated.

The kinetically controlled racemate separation of unsymmetrically substituted organophosphorus compounds is described. Treatment of racemic methyl- t butyl-phenyl-phosphine (1) with a half molar quantity of R-(+)-methyl-phenyl-sulfoxide (8) results in formation of S-(—)-methyl- t butyl-phenyl-phosphine oxide (4) and – after quaternization with allyl bromide - of R-(+)-methyl- t butyl-phenyl-allylphosphonium bromide (5) of ca. 1% optical purity.

Fluorenone diaryldithioketal (4) decomposes photochemically into free 9-arylthio fluorenyl radicals which dimerize under formation of 9.9′-bifluorenyl (6). The reaction behavior of both 4 and 6 under UV irradiation as well as under electron impact conditions can be compared.

For the reaction product of 1 with dimethylformamidedimethylacetal in the presence of hydroxylamine there might exist five possible tautomeric forms 2 a-e. The structure of the title compound was determined to be 2 d by applying carbon-13 NMR spectroscopy to 2 a-e and some derivatives 8-5 in DMSO-d 6 resp. DMSO-d 6 /NaOD.

The spin-labeled imidazolides of phosphorus 1 and 3 were utilized for the conversion of [xxx] aldoximes to nitriles in high yield. It is hypothesized that this transformation under mild, neutral conditions might serve as a model reaction, mimicking the detoxification of phosphorus-inhibited acetyl cholinesterases.

Spin-labeled phosphoryl imidazolides 3, 6, and 7 were prepared and compared to the unsubstituted compound 1 in reactivity towards hydroxy and amino compounds. The transphorphorylation reaction of compounds 3 and 6 was slower than that of 1. The [xxx] reaction of compound 6 was selective towards amines since no reaction occurred with hydroxy compounds. The reaction of compounds 7 was slow with hydroxy compounds and rapid with amines at room temperature. The transphorphorylation reaction of 1 was rapid with both hydroxy and amino compounds at 50-55 °C.

Trichlorophenylmalonates (1) react with benzalacetone (2) to give 4-hydroxy-6-styryl- 2-pyrones (3) and the isomeric 2:1 condensation products 4 and 5 which are interconvertable. Cinnamoylacetone (8) reacts at different temperatures to three isomeric pyrones (9, 10, and 11). Thermal rearrangement of 9 yields 10 and the latter compound at highter temperatures 11.

The isolation and chromatographic separation of “Amylocyanin”, the blue pigment mixture of Streptomyces coelicolor is described. The main component is 5-(hydroxy-3-β-D-ribopyranosyl-pyrid-2-on-5-yl)-imino-3-β-D-ribopyranosyl-2,6-pyridindione (1), as is prooved by degradation reactions, model compounds and spectroscopic data. The nine minor components are α- and β-D-ribopyranosyl- and α- and β-ribofuranosyl derivatives of 1. Degradation with acetic acid/phenylhydrazine yields the isomere 3-α- and 3-β-D-ribopyranosyl- and 3-α- and 3-β-D-ribofuranosyl-5-phenylhydrazono-2,6-pyridindiones 2, 8, 9 and 10; ozonolysis of 1 liberates D-ribose.

Benzanilidoxim-benzylether reacts with C 3 O 2 in chlorobenzene yielding the pyrimidiniumolat 2. S-Alkyl-N,N′-diaryl-isoureas can be converted with C 3 O 2 to 2-alkylthio-l-pyrimidinium-4-olates (3a-f). 2-Ethylthio-2-pyrazolin gives 8-ethyl-7-oxo-2,3-dihydro-7 H-imidazo[2,3-b][1,3]-thiazin-8-ium-5-olat (5a). Starting with O-alkyl-N,N′-disubstituted isoureas and C 3 O 2 the corresponding 1-pyrimidinium-4-olates (6a—d) are obtained.

The preparation of (NSOCl) 3 from sodium azide and thionyl chloride is described.

Fluorosilanes react with lithium salts of hydrazines to give fluorosilylhydrazines. The 19 F NMR spectra of N,N′-bis(difluoromethylsilyl)-N,N′-diphenylhydrazine and N,N′-bis-(difluoroorganylsilyl) - N, N′ - bis (trimethylsilyl)-hydrazines show an AB system for the fluorineatoms at room temperature, which results from hindered rotation about the Si–N bonds. The coalescence temperature of N,N′bis(difluoromethylsilyl)-N,N′-diphenylhydrazine was observed at + 170 °C ± 10 °C.

Isatoic anhydride (1) reacts with ethyl ß-aminocrotonate (2 a) or acetylacetoneimine (2 b) to give 2-methyl-4-quinazolone (6). The formation of 6 can be rationalized as proceeding through the loss of ethyl acetate or acetone from the intermediate 1,2-dihydroquinazolone 5 by a retro-Claisen or retro-Aldol type elimination, respectively.

2-Methoxi-1,3,2-benzodioxastibole is prepared by transesterification of (CH 3 O) 3 Sb with catechol. Recrystallization from m ethanol yields colourless crystals, the structure of which was solved and refined to a conventional R-value of 0.04 with 915 reflections observed. The space group is P 2 1 /n with 4 molecules in the unit cell. Interaction with oxygen atoms of two neighbouring molecules enlarges the coordination number on the antimony to five, thus forming a structure with infinite chains along the α-axis.