Volume 30, Issue 1-2

The crystal structure of Li 5 Sn 2 has been determined. It crystallizes trigonal/rhomboedric, space group R3̅m—D 5 3d , a = 4.74 ± 0.01 Å, c = 19.83 ± 0.03 A, c/a = 4.18. Structural relations between Li 2 Si, Li 9 Ge 4 and Li 5 Sn 2 are discussed.

The crystal structure of Li 7 Sn 2 has been determined. It crystallizes orthorhombic, space group Cmmm–D 19 2h , a = 9.80 ± 0.02 A, b = 13.80 ± 0.02 Å and c = 4.75 ± 0.01 Å, isotypic to Li 7 Ge 2 . The close relations to the structure of Li 7 Pb 2 are shown.

The crystal structure of Li 13 Si 4 , earlier reported as Li 7 Si 2 , has been redetermined. Structural relations between Li 13 Si 4 , Li 7 Pb 2 and Li 3 Sb are shown.

The crystal and molecular structure of β-bromo(diethylaminoethanolato)copper(II) has been determined from three dimensional X-ray diffractometer data. The compound crystallizes in the triclinic space group Pï with one dimer in a unit cell of dimensions α=10.180(II), b=7.999(9), c=6.227(7) Å and a=110.69(4), β=103.12(4), γ=73.82(4)[°]. The structure was refined by least-squares methods using 1944 independent reflexions to give a final R-index of 0,05. The molecule consists of dimeric Cu 2 O 2 -units with Cu—O distances of 1.900(4) Å and 1.914(4) A, respectively. The dimers are additional bridged by bromines, so that a “polymeric” structure results; Cu—Br distances are 2.357(2) and 3.660(2) A, respectively. The Cu—Cu distances are 3.003(2) (oxygen bridges) and 4.506(2) Å (bromine bridges).

The crystal structure of KCd(NCO) 3 has been determinated by threedimensional X-ray diffraction. The crystals are orthorhombic, space group Pnma with the cell dimensions a = 999.3 pm, b = 367.1 pm and c = 1835.4 pm. The cadmium atoms are surrounded octahedrally by six N-atoms. As in the KCdCl 3 -structure N-bridged double chains along the c-axis are formed which are linked together by the potassium atoms.

The structure of the title compound has been determined from three dimensional X-ray data by Patterson and Fourier methods. The crystals are orthorombic, with unit cell dimensions a = 1181,50 pm, b = 943,68 pm, c = 1181,50 pm, space group D 2h 16 and Z = 4. Least squares refinement, by use of 1540 independent reflections measured on a diffractometer has reached R = 5,9%. There are discrete C 7 H 7 Mo(CO) 2 SnCl 3 molecules, the molybdenum-tin bond has been dicussed together with the corresponding bonds in other C 7 H 7 Mo(CO) 2 SnR 3 compounds.

The structures of the title compounds have been determined from three dimensional X-ray data by Patterson and Fourier methods. The crystals of both are orthorombic with the space group D 4 2 -P 2 1 2 1 2 1 . The chloride (2) and the bromide (3) are isomorphous, they have unit cell dimensions a = 642,76 pm, b =1187,27 pm, c =1311,14 pm (2) and 644,59 pm, 1183,78 pm, c = 1321,83 pm (3) and Z = 4. Least squares refinement by use of 1179 (2) and 1037 (3) independent reflections measured on a diffractometer has reached R = 12,5% and R = 7,4% respectively. The molybdenum-bromine bond in 3 is relatively shorter than the molybdenum-chlorine bond in 2, due to greater d π -d π interaction.

The title compounds have been synthesized and characterized, they can be classified as compounds of the series [C 5 H 5 Fe(CO) 2 ] 2 Sn R 2 by their infrared spectra.

Hexacyanoplatinates(IV) M(II) [Pt(CN) 6 ] · x H 2 O (M(II) = Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd; 0 ≦ x ≦ 2) have been prepared. According to their X-ray powder diagrams the compounds crystallize cubic, space group O 5 h —Fm3m, Z = 4, with the exception of the Cr and the Cu salt. Due to JAHN-TELLER-distortion of Cr(II) and Cu(II) the latter compounds crystallize tetragonal. Light absorption spectra of the compounds in the NIR, visible and UV region have been assigned to the d—d transitions of the M(II) electrons in the field of the six N ligands. Crystal field parameters have been determined. In the spectrochemical series, the N atoms of [Pt(CN) 6 ] 2— have a position between NH 3 and ethylenediamine. A new simple method to prepare K 2 [Pt(CN) e ] has been developped.

The synthesis and properties of aryltellurenyl bromides and iodides are described using equivalent amounts of halogen and diaryl ditellurides in non polar solvents.

The reactions of bis(2-biphenylyl) ditelluride with halogens which give 2-biphenylyltellurenyl bromide and 2-biphenylyltellurenyl iodide, bis(2-biphenylyl) ditellurium tetraiodide or 2-biphenylyltellurium triiodide are reported and the properties of these hitherto unknown compounds are described.

Reactions of tin(IV) chloride with monofunctional bidentate Schiff bases, having the general formula in different stoichiometric ratios have yielded SnCl 4 • SBH and SnCl 4 (SBH) 2 type of products (where SBH is the monofunctional bidentate Schiff base). The resulting derivatives have been characterized on the basis of elemental analysis and IR spectra. Conductivity measurements show them to be nonelectrolytes.

The 1:1 and 2:3 molar reactions of La(III), Pr(III) and Nd(III) isopropoxides with the bifunctional tetradentate Schiff base, ethylenediamine bis-2,4-pentanedione [AA 2 (CH 2 ) 2 H 2 ] have been investigated in the medium of dry benzene. Ln(O-i-C 3 H 7 ) [AA 2 (CH 2 ) 2 ] and Ln 2 [AA 2 (CH 2 ) 2 ] 3 [where, Ln = La(III), Pr(III) or Nd(III) and AA 2 (CH 2 ) 2 - 2 anion of the corresponding Schiff base, AA 2 (CH 2 ) 2 H 2 ] type of compounds have been obtained in almost quantitative yields and in a state of sufficient purity. The 1:1 derivatives have been shown to undergo exchange reactions with an excess of tert-butyl alcohol leading to the formation of Ln(O-tert-C 4 H 9 ) [AA 2 (CH 2 ) 2 ] [where, Ln = La(III), Pr(III) or Nd(III)] type of derivatives. The ebullioscopic determination of molecular weights shows that the 1:1 derivatives are dimeric, whereas 2:3 derivatives are monomeric in boiling benzene. On the basis of elemental analysis, exchange reactions, molecular weight determinations and IR spectra, plausible structures for the resulting 1:1 and 2:3 complexes have been indicated.

Dimethylsulfane-borane, (CH 3 ) 2 SBH 3 , reacts with X 2 , HX and BX 3 to give (CH 3 ) 2 SBH 2 X and (CH 3 ) 2 SBHX 2 (X = Br, I). Although BI 3 is the strongest Lewis-acid amongst the boron compounds, it does not form (CH 3 ) 2 SBI 3 but (CH 3 ) 2 SBHI 2 and B 2 H 6 , when it is mixed with (CH 3 ) 2 SBH 3 . 1 H—NMR results indicate an increase in the donor-acceptor bond strengths with decreasing n in the series (CH 3 ) 2 SBH n X 3-n .

By the reaction of PCl 3 with dialkylphosphites in the presence of pyridin, compounds of type 2 are obtained, the structure of which is proven by NMR and X-ray photoelectron spectra. Some chemical and physical properties are described.

The preparation of ammonium(2:5)-molybdate from aqueous solution is described. The Raman and infrared spectra show great resemblance to the spectra of ammonium(3:8)-molybdate tetrahydrate. As first intermediary phase by thermal decomposition the polymeric ammonium octamolybdate is formed.

The new compounds Sr 2 Bi, Ba 2 Sb, Sr 5 Bi 3 , Ba 5 Sb 3 and Ba 5 Bi 3 were prepared and their structures determined. The A 2 B-compounds crystallize tetragonal bodycentered and are isotypic to Ca 2 Sb, Ca 2 Bi and Sr 2 Sb. The A 5 B 3 -compounds build up the Mn 5 Si 3 -structure type. In both structures the element (V) atoms are coordinated only to earth alkali atoms.

Mn(II) ion catalysis in the oxidation of lactic acid by chromic acid has been investigated between the pH range 2.0 to 4.0; [H + ] = 0.1 to 0.4 and [H + ] ≥1.1 M. Activation parameters for catalysed and uncatalysed reactions have been evaluated. While C—H bond rupture occurs in the uncatalysed reaction, the rate limiting step of the catalysed reaction involves C-C bond fission.

The reactions of uranium oxysulphide with selected oxysulphides of rare earths (La, Gd, Yb) and Y were investigated. Several new phases, identified as uranium-rare earth oxysulphides were found. The chemical compositions and lattice constants of those compounds were determined.

New modifications of KInS 2 and RbInS 2 were found after high pressure treatment and quenching to ambient conditions. The tetragonal modifications KInS 2 -II and RbInS 2 -II are isotypic with TISe. KInS 2 -II is metastable at all p,T-conditions investigated. The stable high pressure modification KInS 2 -III has a-NaFeO 2 -structure. Pressure treatment of CsInS 2 yielded an unknown phase with a diffuse X-ray pattern.

The signal with g = 2.0280, given by blue colored solutions of polysulfides in dimethylformamide, has been shown through quantitative ESR measurements to arise from the trisulfide radical ion S 3 -.

The SO 2 -insertion into tin-carbon bonds of mixed tetraorganostannanes, R 3 SnR′ (R=C 6 H 5 , CH 3 ; R'=CH 3 , C 6 H 5 , CH 2 =CH), is determined by the nucleophilicity of the organic residue attached to metal and shows a decreasing rate in the order aryl > alkenyl > alkyl. A correlation to Taft’s constant is given. The behaviour of triphenylvinyltin toward sulfur dioxide is in good agreement with this rule, as the insertion of one or two moles of SO 2 takes place only into Sn—C 6 H 5 bond.

Mössbauer and infrared spectra of the alkali metal ferricyanides M 3 I [Fe(CN) 6 ] · nH 2 O, where M I = H, Li and Na were studied at room temperature. All the three compounds displayed a doublet with small quadrupole splitting (ΔΕ Q ). Infrared spectra of these compounds in solid state gave two frequencies for C=N stretching vibrations with their separation (Δv) in increasing order which was found to be linearly correlated with ΔE Q . A plausible explanation has been given in terms of the interaction of Li + and Na + cations with the CN - ligands of octahedrally symmetric ferricyanide anion [Fe(CN) 6 ] 3- similar to that of hydrogen atoms which are hydrogen bonded in H 3 Fe(CN) 6 .

The kinetics of the reaction between peroxodisulphate and p-chloro and p-bromo mandelic acid catalysed by silver(I)ions have been studied. The rate of peroxodisulphate disappearance was found to be dependent (i) on [S 2 O 8 -2 ] (ii) on [Ag + ]. The rate is independent of the substituted acid concentration. Thermodynamic parameters have been evaluated. A mechanism of the oxidation of substituted mandelic acid by peroxodisulphate catalysed by silver(I) has been suggested.

Sorption of ammine complexes of Cu 2+ , Ni 2+ , Zn 2+ and Cd 2 + on ferric phosphate has been studied at different ionic concentration in the external solution. It has been found that q A and Kd values attain a maximum with increasing concentration (0.02 ᴹ) beyond which a fall is observed. Selectivity quotients of the exchanger material towards competing pairs of the metal ammine ions e.g. (Cu(II)—Zn(II), Cu(II)—Cd(II) and Cu(II)—Ni(II) have also been measured as a function of the concentration of the external solution. The selectivity effects in general, decrease with increase in the external concentration. The q A and selectivity follows the same trend i.e. Zn 2+ > Cd 2+ > Cu 2+ > Ni 2+ .

2-Amino cyclopentene-1-dithiocarboxylic acid (ACDA) reduces Cu(II) and Rh(III) to form univalent complexes of composition Cu(ACDA), 2 H 2 O and Rh(ACDA) 2 H 2 O, the oxidised species being a dimer of ACDA. The Cu(I) may be obtained in higher yield by reacting cuprous iodide with ammonium salt of ACDA. A compound of composition Rh(ACDA) (PPh 3 ) (H 2 O) is obtained by reacting ACDA with Rh(PPh 3 ) 3 Cl. With Hg(II) a normal bis complex is formed. The compounds have been characterized by their infrared and electronic spectra, magnetic moment measurement and thermal analysis. In the complexes bonding occur through NH 2 and deprotonated thiol group. A tentative mechanism for the formation of reduced metal complexes has been suggested.

Aqueous solutions of alkyl sulphates containing small amounts of the free alkanol differ in their dissolving properties for polycyclic aromatic hydrocarbons from aqueous solutions of the pure soap in concentrations near the CMC. The differences are observed only near the CMC of the pure soap, where the soap solutions containing free alkanol have a minimum of the surface tension. The observed alterations are deviations from the Lambert-Beer law, energy transfer, and changes of the fluorescence quantum efficiencies, when the soap concentration is varied. The different results are consistent with the assumption that microcristalline molecular van der Waals associations are brought into solution by the soap solutions which were studied.

The stereochemical course of the ‘phosphine oxide cleavage’ of chiral R-(+)-methylphenyl-α-naphthyl-allyl-phosphonium bromide is reported. While the α-naphthyl group is cleaved by alkali with predominant retention of configuration at the central phosphorus atom, the allyl group is split off with predominant inversion.

Treatment of 5-arylidene-4-methylmercapto-hydantoin (1a,b) and 1-phenyl-4-thiohydantoin (3) with aromatic amines gave 5-arylidene-4-arylimino hydantoin (2 a-h) and 4-arylimino- l -phenyl-hydantoin (4a-c) respectively. 2 a and 4 a were hydrolysed with concentrated hydrochloric acid and gave 5-benzylidene-hydantoin and 1-phenyl-hydantoin respectively. N 2 -phenylglycocyamidine (7) was found to condense with aromatic aldehydes yielding (6a-c). Compound 6a was also obtained from 5-benzylidene-2-methylmercaptohydantoin (5) and aniline. Treatment of 5-arylazo-2-methylmercapto-hydantoin (8a-e) with aromatic amines gave the products 9 a-k. The compound 9 a was hydrolysed with a mixture of concentrated hydrochloric acid and acetic acid yielding (10).

The reaction of imines with various electrophiles have afforded only N-alkylated products, contrary to earlier reports.

By investigations in the systems Mg—Zn—P (As) we found two ternary phases of the formulas Mg 1, 75 Zn 1, 25 P 2 and Mg 2 ZnAs 2 , which crystallize in a trigonal lattice. We suppose a modified anti-La 2 O 3 -type structure.

By further investigation of the system Li—Au—Sb we found a second 1 cubic phase of the formula LiAuSb which crystallizes in the spacegroup T d 2 —F 4̅ 3 m, the lattice-constant is a = 6.32 8 Å.

By reaction of triphenylphosphine and carbon tetrachloride with methane sulfonamide (1 a) and the sulfamic acid derivatives (1 b-g) N-triphenylphosphoranylidene compounds of these substances could be obtained.

The IR spectrum of LaGaO 3 is reported and discussed in comparison with those of related compounds. The valence force constant for the Ga–O bonds is also estimated.

The kinetics of the reactions of p-nitrophenyl thiolacetate with several amines in acetonitrile was studied. Hydrazine exhibits considerably greater nucleophilicity than expected from its pK a value. Common mechanism is suggested for the aminolysis of the thiol ester and its oxygen analogue.

3-Hydroxy-2-phenyl- 1.4-naphthoquinone is cyclodehydrogenated at 250°C in the presence of palladium yielding β-brazanquinone.

The reaction of o-aminophenylglyoxal dimethylacetales with sodium pyruvate in the presence of sodium ethoxide yields 4-dimethoxymethyl-quinoline-2-carboxylic acids which give the title compounds on acid hydrolysis.