W.-W. Du Mont

α-Eliminierungsreaktionen an trihalogengermylphosphinen

Abstract Germaniumtetrachloride and -bromide react with equimolar amounts of di-tert-butyl(trimethylsilyl)phosphine yielding di-tert-butyltrichloro- and -tribromogermylphosphine by a substitution reaction, as well as the isomeric di-tert-butylhalogenophosphine-dihalogenogermylenes which are formed by a redox reaction. Both types of compounds react with tertiary phosphines by elimination of di-tert-butylhalogenophosphine forming triorganophosphine-dichloro- and -dibromo-germylenes. The process of formation and the properties of the new germylenes are discussed.

Organometallarsine : IX. t-butyl(trimethylelement(IVB))arsine und ihre pentacarbonylchrom-, -molybdän- und -wolfram-komplexe

Abstract Di-t-butylchloroarsine reacts with t-butyllithium to give tri-t-butylarsine and with trimethylchlorosilane-magnesium-tetrahydrofuran under formation of di-t-butyl(trimethylsilyl)arsine. Tris(trimethylsilyl)arsine was obtained in a similar way from arsenic trichloride with trimethylchlorosilane-magnesium-HMPA. Trimethylsilylarsines react with trimethylchloro-germane and -stannane to give the corresponding trimethyl-germyl- and -stannyl-arsines. Organometalarsines react with hexacarbonyl-chromium, -molybdenum, or -tungsten with formation of pentacarbonyl(organometalarsine)-chromium, -molybdenum, or -tungsten complexes. NMR, IR, Raman, and He(I)-PE data of the new bulky arsine ligands and of some complexes are reported.

119mSn-Mössbauer-spektren von funktionell substituierten stannylenen und ihren stannio-komplexen mit chrom, molybdän- und wolfram-carbonyl-acceptoren

Abstract 119 m Sn Mossbauer data for a series of base-stabilized, intermolecularly associated tin(II) compounds ith O, Cl, P and As atoms bonded to tin are compared with isomer shifts (IS) and quadrupole splittings (QS) of their stannio complex derivatives with Cr, Mo and W carbonyls. Coordination at the tin lone-pair atom decreases IS to ca. 2.1 ± 0.2 mm s −1 and increases the QS. QS values reflect the highly associated nature of the complexes (CO) 5 MSn(Cl)E(t-Bu) 2 (M Cr, W; E  P, As) which are bridged through μ-E(t-Bu) 2 groups.

Tin-119m Mössbauer spectra of trimethyltin phosphines used as ligands in transition metal carbonyl complexes

Abstract Tin 119m Mossbauer Quadrupole Splitting (Q.S.) data for several trimethyltin amines, phosphines, arsines, stibines and sulfides are compared with the larger values found for the transition metal carbonyl complexes of the phosphine and sulfide derivatives which reveal the polarizing effect of donor action by the adjacent group V or VI atom.

Two Organic Diselenides: Dimesityl Diselenide and Bis(2,4,6-triisopropylphenyl) Diselenide

The organic diselenides dimesityl diselenide [C 18 H 22 -Se 2 , (I)] and bis(2,4,6-triisopropylphenyl) diselenide [C 30 H 46 Se 2 , (II)] display normal diselenide geometries: Se-Se bond lengths are 2.3341(6) in (I) and 2.3389 (6) A in (II), and the absolute C-Se-Se-C torsion angles are 83.96 (12) in (I) and 73.38 (16)° in (II).

Austauschreaktionen an organostannylphosphinen: Identifizierung einer stabilen zwischenstufe

Abstract Monomeric 1 : 1 adducts of di-t-butyl(chlorodimethylstannyl)phosphine and dimethyltin dichloride are formed in solution by mixing equimolar amounts of the two components or by mixing dimethyltin dichloride and di-t-butyl(trimethylsilyl)phosphine in a 2 : 1 molar ratio. NMR, IR, Raman and 119 mSn Mossbauer data are in agreement with a symmetrical structure with two equivalent (CH3)2SnCl groups bridged by di-t-butylphosphine and chloro groups. The bonding and stability of the adduct are discussed.

Tetracarbonyl[telluro-bis-di-t-butylphosphan]chrom(0). Der erste tellurophosphan-chelatkomplex

Abstract Tetracarbonyl(norbornadiene)chromium(0) reacts with tellurobis(di-t-butylphosphane) to give red crystals of the complex [Cr(CO)4P2-t-Bu4Te] in high yield IR, 1H, 13C, 31P and 125Te NMR spectra as well as the mass spectra agree with a chelate structure which includes the new four-membered CrP2Te heterocyclic group.

Substitutionsreaktionen an komplexgebundenen carbenanalogen: Die synthese von pentacarbonyl[chlor(diorganylphosphino)- und -arsino)stannylen]wolfram(0)

Summary Pentacarbonyl[dichloro(tetrahydrofuran)stannylene]tungsten(0) reacts with di-t-butyl(trimethylsilyl)-phosphine and -arsine with elimination of (CH3)3SiCl and thf to give new stable phosphine- or arsine-substituted stannylene complexes (W(CO)5[Sn(Cl)ER2], E = P, As; R = t-C4H9).