Volume 35, Issue 5

Aminolysis of the P-chlorofunctional carbodiphosphorane Ph 3 P = C = PPh 2 Cl (1) affords the diorganylamino substituted phosphonium salts (3a-e, R = alkyl), which can be dehydrohalogenated in good yield by NaH to give the neutral compounds Ph 3 P = C - PP 2 (NR 2 ) (4a-e). The structure of the hitherto unknown amino-carbodiphosphoranes has been confirmed by 31 P{ 1 H} and 13 C{ 1 H} NMR data as well as by hydrolysis to give 5, hydrochlorination to 6b, e and methylation to 7a, e.

The P7-skeleton of trilithiumheptaphosphide, Li 3 P 7 (1), was proved to possess the earlier reported tricyclic structure [2] by complete analysis of the 31 P NMR spectrum of 6 Li 3 P 7 observed at - 60 °C. The 6 Li isotopic substitution was carried out to avoid the line broadening caused by the large quadrupole moment of the 7 Li isotope. The unambiguous elucidation of the Li 3 P 7 structure confirmed that the exchange process which causes all P atoms to become equivalent above room temperature is analogous to that in bullvalene. A comparison of the chemical shifts with those of (Me 3 Si) 3 P 7 leads to the result that the P 7 -skeleton in Li 3 P 7 is noticeably compressed along its threefold axis, thus indicating a predominant ionic character.

The complexes AsPh 4 [Cl 4 V = N-Cl] and AsPh 4 [VOCl 4 ] are prepared by the reaction of AsPh 4 Cl with Cl 3 VNCl and VOCl 3 , respectively. The IR spectra indicate C 4v symmetry for the complex anions with multiple VN and VO bonds and a linear arrangement for the VNCl-group. AsPh 4 [VOCl 4 ] crystallizes in the tetragonal space group P4/n with two formula units in the unit cell. The crystal structure was solved by X-ray diffraction methods (R = 0,062, 1096 observed, independent reflexions). The structure consists of AsPh 4 + cations and [VOCl 4 ]- anions with symmetry C 4v . The extremely short VO bond length corresponds with a VO triple; its steric requirements cause the relatively large bond angle OVCl of 103.4°.

SeCF 2 is prepared on a preparative scale reacting AII 3 with Hg(SeCF 3 ) 2 in octamethyl-cyclotetrasiloxane. It adds MF [M = Cs, Tl, [(CH 3 ) 4 N] and Ag] to form MSeCF 3 . AgSeCF 3 was also synthesized from AgF and B(SeCF 3 ) 3 . Under the influence of sunlight SeCF 2 dissolved in CFCI 3 dimerizes quantitatively to 2,2,4,4-tetrafluoro-1,3-diselenetane, which above 360 °C pyrolyses to the monomer. The cyclic dimer reacts with B(SeCF 3 ) 3 to give (CF 3 Se) 2 CSe. The reaction of AgSeCF 3 with CF n Cl 3-n SCl leads to CF 3 SeSCF n Cl 3-n (n = 1, 2, 3). IR, NMR and mass spectra of the newly prepared compounds were presented.

The electrolysis of P 4 /HSO 3 F mixtures does not yield detectable phosphorus-polyatomic cations; the intense coloration of the electrolyte is due to the known sulfur polyatomic cations originating from decomposition of HSO 3 F.

The electrochemical synthesis of group VI B metal carbonyls and phosphane derivatives thereof from suitable metal complexes of oxidation state +III (acetylacetonates, chloropyridin compounds) and from metal anodes is described.

The reductive and oxidative half-wave potentials of some phenyl-substituted derivatives of 1-phenyl-5-mercaptotetrazole were evaluated in acetonitrile. Linear relationships between measured half-wave potentials and substituent values given by Hammett as well as influences of substituents on the electrochemical reactivity of 1-phenyl-5-mercaptotetrazoles has been studied. Furthermore, a reduction scheme of these compounds in acetonitrile at the Hg-Elektrode was established.

Phenyllead Compounds, Methyllead Compounds, Organolead-S-mercaptocarboxylic Acids Triphenyl-and diphenyllead derivatives of mercaptocarboxylic acids (H2Mc) with general formulas Ph3Pb(HMc), (Ph3Pb)2Mc, Ph2Pb(HMc)2 and R2Pb(Mc) (R = Ph, Me) have been prepared by gentle reaction of H2Mc with Ph3PbOH, (Ph2PbO)n or Me2Pb(OH)2 in CHC13. According to spectroscopic data the ligand in all compounds is bound to Pb through S. Ph3Pb(HMc) (HMc = SCH2COOH, SCH2CH2COOH, SCH(CH3)COOH, SCH(COOH)CH2COOH forms dimers in the solid state and in CC14, Ph2Pb(CH2CH2COOH)2 forms polymers via H-bonded COOH groups. Ph3Pb(o-SC6H4COOH) is monomeric. For R2Pb(Mc) polymeric structures are proposed. Me3PbOH and H2Mc react to give an inter-mediate, which disproportionates to give Me2Pb(Mc) (Mc = SCH2COO, SCH2CH2COO) and Me4Pb. Triphenyl- and diphenyllead derivatives of mercaptocarboxylic acids (H 2 Mc) with general formulas Ph 3 Pb(HMc), (Ph 3 Pb) 2 Mc, Ph 2 Pb(HMc) 2 and R 2 Pb(Mc) (R = Ph, Me) have been prepared by gentle reaction of H 2 Mc with Ph 3 PbOH, (Ph 2 PbO)n or Me 2 Pb(OH) 2 in CHCl 3 . According to spectroscopic data the ligand in all compounds is bound to Pb through S. Ph 3 Pb(HMc) (HMc = SCH 2 COOH, SCH 2 CH 2 COOH, SCH(CH 3 )COOH, SCH(COOH)CH 2 COOH forms dimers in the solid state and in CCl 4 , Ph 2 Pb(CH 2 CH 2 COOH) 2 forms polymers via H-bonded COOH groups. Ph 3 Pb(o-SC 6 H 4 COOH) is monomeric. For R 2 Pb(Mc) polymeric structures are proposed. Me 3 PbOH and H 2 Mc react to give an intermediate, which disproportionates to give Me 2 Pb(Mc) (Mc = SCH 2 COO, SCH 2 CH 2 COO) and Me 4 Pb.

Addition of phosphorus(III) ligands, L (L = tertiary phosphine, phosphite) to the reaction mixture of allyldifluorophosphite (1) with (C 6 H 5 CN) 2 MCl 2 (2) (M = Pd, Pt) was found to produce two types of products: after a shorter reaction period, monofluorophosphonate complexes of the previously known type trans-L 2 MCl(POF 2 ) (6) are obtained while over prolonged periods of time bis-fluorophosphonato complexes, trans-L 2 M(POF 2 ) 2 (7) are formed. By contrast, Bu n OPF 2 (8) yields a mixture of trans-L 2 PtCl(POF 2 ) (6) and trons-L 2 PtCl[(Bu nO )(F)PO] (10) (L = Ph 3 P), the latter originating from (Bu n O) 2 PF formed by ligand scrambling in Bu n OPF 2 ; no products containing more than one fluorophosphonate group are formed in this case. The new monofluorophosphite, (CH 2 = CHCH 2 0O) 2 PF (10) was found to react rapidly with (C 6 H 5 CN) 2 PtCl 2 /L with formation of L 2 PtCl[(CH 2 =CHCH 2 O)(F)P0] (11). Compound characterization was by IR, 19 F and 31 P NMR spectroscopy.

Reaction of [OsX 6 ] 2- (X = CI, Br, I) with oxalic acid in water gives the very stable and deeply coloured new complexes [OsX40x] 2- which can be precipitated as alkali or tetraalkylammonium salts. The salts with long-chain alkylammonium ions are soluble in all common no polar solvents. The IR and Ra spectra and the depolarization ratios are consistent with the local C 2v -symmetry. The coupling between the vibrations of coordinated oxalate and with the skeletal [OsX 4 O 2 ]-modes is apparently small. The optical spectra have been studied at low temperature (10 K). Analogous to [OsXe] 2- the very intense absorptions in the UV and VIS are assigned to the electric dipole allowed electron transfer from "(π+σ)t 1u , πt 2U (γ7), πt 2u (γ8) and (σ+π)t 1u " to "dt 2g ". By the descent in symmetry each of these transitions is further split in three components (A 1 , B 1 , B 2 ) corresponding to the three different groups of ligands, X 2 tr- , X 2 c. and ox. The distinction between the X 2 tr. →Os and X 2 c- → Os is caused by a static trans-effect and depends on the difference of the optical electronegativities induced by ox. This splitting is not observed for [OsCl 4 ox] 2- but is about 900 cm -1 for [OsBr 4 ox] 2- and 1200 cm -1 for [OsI4ox] 2- . The well defined bands in the NIR and VIS are assigned to the intraconfigurational d-dtransitions between the spin-orbit components in the octahedral doublegroup O h * splitted by the lower C 2v -symmetry. Some of the zero-phonon transitions within the split of the 3 T lg , O h -groundstate exhibit extremely high intensities (e~2500 cm 2 /mmol). The assignment of these transitions is improved by the electronic Ra spectra. The finestructure of some of the d-d-transitions originates from coupling with A 1 vibrational modes especially with ν s (C-O).

Spectroscopically pure PaPc 2 has been prepared by reaction between PaI 4 · 4 CH 3 CN and o-phthalic acid dinitrile in 1-chloronaphthalene followed by sublimation at 5 · 10 -3 Pa in a temperature profile with three clearly defined zones (520 °C/350 °C/room temperature). This procedure gives a product almost completely free of H 2 Pc impurity which is known to have been present in previously reported complexes of the type AnPc 2 . Thus, the trace of H 2 Pc in the substance could only be detected by derivative spectroscopy. X-ray powder diffraction shows the compound to be isostructural with ThPc 2 and UPc 2 . The ligand spectrum is typical of AnPc 2 complexes, f-f Bands observed in a solid state spectrum provide additional proof that the compound is Pa IV Pc 2 .

1,3-Dipolar reagents with an unsaturated CNO- or CNN-skeleton undergo 1,3-organoboration by triorganoboranes. On the other hand, the unsaturated NNO-skeletons in azoxybenzene or nitrous-oxide are reduced to the corresponding NN-fragment by trialkylboranes. The 1,3-addition of aminoborane Cl 2 BNMe 2 to the aldimineoxide PhHC = NMe-0 represents one of the rare examples of analogous reactivity of BN- and CC-double bonds. O-Borylhydroxylamines PhHCR-NMe-OBR 2 are reduced by BR′ 3 to PhHCR-NMe-BR′ 2 and R′0-BR 2 . Similar reduction products are isolated from liquid-phase thermolysis of PhHCEt-NMe-OBEt 2 (16), whereas gas-phase thermolysis of 16 gives PhCH = NMe, (EtBO)3, and C 4 H 10 .

Reaction of imidodiphosphoric tetraphenylester with HgO yields the twelve-membered ring system 1, the properties, NMR and X-ray structural data of which are reported. A reaction mechanism is suggested. Reaction product from imidodiphosphoric tetraphenyl-ester and C 6 H 5 HgOH is N-phenylmercury-bis(phosphoric diphenylester)-imide (2).

A spirometallocyclic complex of ruthenium with (CH 3 ) 2 P(CH 2 ) 2 , (CH 3 ) 2 PCH 2 and two (CH 3 ) 3 P ligands (formula 5) is synthesized from (CH 3 ) 2 P(CH 2 ) 2 Li and trans-[(CH 3 ) 3 P] 4 RuCl 2 in the molar ratio 2:1. Two equivalents of (CH 3 ) 3 P are liberated and the ionic complex trans-[(CH 3 ) 3 P] 4 Ru[CH 2 P(CH 3 ) 3 ]Cl + Cl - is formed as a by-product. The products were characterized by analytical and spectroscopic data.

Organic radicals generated by the oxidation of aldehydes, alcohols and ethers under reducing conditions are trapped by vitamin B 12r to yield substituted organocobalamins. From higher n-alkyl aldehydes, acylcobalamins are formed. With acetaldehyde, a mixture of acetylcobalamin and of methylcobalamin is obtained due to the spontaneous decarbonylation of the CH 3 CO· radical. From saturated alcohols, w-hydroxyalkylcobalamins are produced, while w-alkoxyalkylcobalamins are formed in the corresponding reactions with radicals generated from ethers. Maximum yields of the organocobalamins are obtained if reducing conditions are maintained during the oxidation of the organic substrates. This is conveniently achieved by using V(III) salts as the reductants and the slow addition of oxidants (e.g. of O 2 , H 2 O 2 , Fenton reagent, or of electrochemically generated oxidizing equivalents). With 5′-deoxyadenosine, 5′-deoxyadenosylcobalamin is formed.

The reactions of tricarbonyl nitrosyl cobalt with tri-tert-butylphosphine, di(tert-butyl)-trimethylsilyl-, -germyl-, -stannylphosphine, tert-butyl-bis(trimethylsilyl)-, -(germyl)-, -(stannyl)phosphine, as well as with tris(trimethylsilyl)-, -(germyl)-, and -(stannyl-phosphine result in the elimination of one CO-ligand and the formation of corresponding dicarbonyl-nitrosyl-organometal phosphine cobalt complexes. The NMR spectra of the products are reported and discussed.

The silyl azides R 3 SiN 3 (R = Me, Ph) react with dicyclopentadienyl vanadium Cp 2 V under formation of (Cp 2 V) 2 NSiMe 3 and Cp 2 VNSiPh 3 , respectively. By reaction with Me 3 SiN=NSiMe 3 , (Cp 2 V) 2 NSiMe 3 is transformed into CpVNN(SiMe 3 ) 2 and Cp 2 VNSiMe 3 (la). According to X-ray analysis, 1a contains a linear V≡N-Si-group. 1a decomposes under formation of (CpV) 2 (NSiMe 3 ) 3 . Reaction of 1a with Me 3 SnCl leads to [CpVCl(NSiMe 3 )] 2 (two isomers).

The tetrahedral wurtzite type structure of MgSiN 2 has been refined with the help of neutron diffraction. The interatomic distances for Mg-N and Si-N are in complete agreement with the previously known values and the SiN 4 tetrahedra in the structure are slightly deformed.

In this article we describe the synthesis of TRIPA, dodecamethyl bisimidotriphosphoramide (C 12 H 36 N 7 O 3 P 3 ) and of its complexes with various lanthanide-nitrates. Five types of complexes have been isolated according to the compositions, X-ray diffraction patterns and IR spectra. 1. M(N0 3 ) 3 (TRIPA) 3 (acetone) M = La, Pr, Nd, 2. M(N0 3 ) 3 (TRIPA) M = Y, 3. M(N0 3 ) 3 (TRIPA) 2 (nitromethane) M = Er, Y, 4. M(N0 3 ) 3 (TRIPA) 2 (acetone) M = Sm, Gd, Dy, Er, Y (type I), 5. M(N0 3 ) 3 (TRIPA) 2 (acetone) M = Y (type II). The yttrium complexes, type I and II, are isomeric. IR spectra are given together with the NMR spectra. It is concluded that in all complexes the three TRIPA oxygens are coordinated, except in group 1. The nitrate groups in group 2 to 5 are involved in the coordination, particularly in the type 2 complex, where there are bidentate nitrate groups. There seems to be a difference in the conformation of the TRIPA molecules between the free ligand, the complexes in group 1, in group 2 and in group 3, 4, 5 Hygroscopic TRIPA can be easily confused with a stable mono-hydrate, TRIPA · H 2 O.

Semicobaltates (Co-1/2) containing olefin and trimethylphosphane ligands are synthe-sized from Co(olefin)(PMe 3 ) 3 and potassium metal. The X-ray crystal structure determination of the title compound shows that the unit cell contains two K atoms in equal ionic contact with the ethylene ligands of four Co(C 2 H 4 )(PMe 3 ) 3 complex units, two of which are interacting with both K atoms. In solution the semicobaltates exist in hydrocarbon solvents under argon only, while in contrast under ethylene or nitrogen atmospheres or in donor solvents disproportionation occurs to give Co(O) and Co(-I) species. Allgemeines

The ternary compounds Mg 2.5 Ni 11.5 P 7 , Ca 2.1 Ni 11.9 P 7 and Ca 2.3 Ni 11.7 As 7 were structurally characterized. They are isotypic and crystallize in the Zr 2 Fe 12 P 7 -type (space group P6̅) with the following constants: Mg 2.5 NI 11.5 P 7 , a = 907,9(1) pm, c = 355,7(1) pm, Ca 2.1 Ni 11.9 P 7 , a = 910.3(1) pm, c = 367.6(1) pm, Ca 2.3 NI 11.7 AS 7 , a = 940.4(1) p m , c = 381.6(1) pm.

The new compounds Tb 6 Br 7 and Er 6 I 7 are formed from the trihalides with an excess of metal in sealed tantalum containers. X-ray structure investigations [space group C2/m; Tb 6 Br 7 (Er 6 I 7 ): a = 2057.1 (2137.5), b = 379.3 (386.9), c = 1180.0 (1231.9) pm, β = 124.59° (123.50°)] show one-dimensional regions connected by Ln-Ln bonds. The structure type can be described in terms of Ln 6 X 12 -clusters which are linked via edges of Ln 6 -octahedra to form double strings. The structure is derived from an FCC arrangement of halogen atoms part of which is systematically substituted by Ln 6 -octahedra.

1-Methyl-, 1-ethyl-, 1,2-dimethyl-and 1,2,3,4-tetramethylimidazole react with pentacarbonyliron to yield [FeIm 6 ][Fe(CO) 8 ] (1), [FeIm 6 ][Fe(CO) 4 ] 2 (2), [FeIm 4 ][Fe(CO) 4 ] (3) and Fe(Im)(CO) 2 (4) (Im = substituted imidazole). The crystal and molecular structures of 1 and 2 have been determined by X-ray diffraction. For 1 and 2 agreement between calculated and measured Mössbauer absorption intensities was obtained by taking into account Debye-Waller-factors, which were derived from the X-ray diffraction experiments.

61 Ni NMR chemical shifts and 61 Ni 31 P NMR coupling constants are reported for complexes of the type [(CH 3 ) 3 M] n [ t C 4 H 9 ] 3-n PNi(CO) 3 (M = Si, Ge, Sn; n = 1, 2, 3) and related to 55 Mn and 59 Co chemical shifts of the corresponding trinitrosylmanganese and dicarbonylnitrosylcobalt complexes.

Hydrous zirconium dioxide is used in column experiments for separating the halide ions as well as for isotope fractionation of chlorine. The preparation of the zirconium dioxide particles is carried out by homogeneous hydrolysis of a zirconyl chloride solution using hexamethylenetetramine. The separation order of the halides is I - , Br - and Cl - in contrast to the inverse separation order using a strongly basic anion exchange resin. In chlorine isotope separation experiments an enrichment of 35 Cl - is found in the first fractions, whereas the last fractions show a significant enrichment of 37 C1 - . This also indicates an inversion of the isotope separation compared with a strongly basic anion exchange resin. A dependence of the isotope fractionation on the concentration of the NaNO 3 solution used as eluant is found. With increasing concentration the isotope fractionation decreases. Using a 0.5 M NaNO 3 solution the elementary separation effect was calculated e = 6,1 · 10 -4 . This is one of the highest isotope fractionations known in a chloride isotope exchange system. The results show that the electrolyte behaviour of isotopes is comparable to that of a series of homologous elements.

a,β Unsaturated ketones are selectively hydrogenated to ketones in homogeneous bulk-catalysis under mild conditions by iridium-and ruthenium complexes. The range of mean turnover is from 6 to 196 depending on substrate, catalyst and reaction conditions. Selectivity ketone/alcohol depends on the degree of conversion and exceeds 100 on conversion of 90%.