Manfred Fild

Cleavage of the silicon–carbon bond by a phosphorus fluoride: methylene(bis)tetrafluorophosphorane

Methylene(bis)tetrafluorophosphorane has been prepared by cleavage of the Si–C bond of 1,1,3,3-tetra-methyl-1,3-disilacyclobutane with phosphorus penta-fluoride; it has been characterized by chemical means and by n.m.r. and mass spectroscopy.

Darstellung und Strukturen von 2,2,4,4-Tetrafluor-1,3-diphosphetanen und -1,3-diphosphetan-disulfiden / Synthesis and Structures of 2,2,4,4-Tetrafluoro-1,3-diphosphetanes and of -1,3-diphosphetane Disulfides

Abstract A simple route to 1,3-diphosphetanes [RPCF2]2 [R = Ph, Me, But] is described. The phosphaalkene intermediates RP=CF2, as well as the corresponding disulfides [R(S)PCF2]2 have been characterized. The crystal structures of [PhPCF2]2, and of the sulfides [Ph(S)PCF2]2 and [But(S)PCF2]2 are reported.

1,3,5-Triphosphorinane. Synthese und Struktur der Isomeren des 1,3,5-Triphenyl-1,3,5-triphosphorinans/ 1,3,5-Triphosphorinanes. Synthesis and Structure of the Isomers of 1,3,5-Triphenyl-1,3,5-triphosphorinane

The reaction of lithiated Ph(H)PCH2P(H)Ph with (ClCH2)2PPh yields 1,3,5-Triphenyl-1,3,5- triphosphorinane (1) as a mixture of two isomers. The isomers have been separated by column chromatography and characterized by NMR spectroscopy and single crystal X-ray diffraction as the eq-eq-eq (1a) and eq-eq-ax-isomers (1b). (1a) crystallizes with a = 1326.9(3) pm and c = 933.4(3) pm in the rhombohedral space group R3 and displays 3-fold symmetry, showing an eq-eq-eq conformation. (1b) crystallizes in the monoclinic space group P21/c with a = 984.09(12) pm, b = 1757.5(2) pm, c = 1083.13(12) pm, β = 93.329(2)° and displays an ax-eq-eq conformation.

Methylenverbindungen von Nichtmetallen, III [1]. Metallcarbonyl-Komplexe mit methylenverbrückten Diphosphor-Liganden / Methylene Compounds of Non-Metals, III [1] Metal Carbonyl Complexes of Methylene-Bridged Diphosphorus Ligands

Compounds of the type R2PCH2PR2 (R = PriO, Me2N) react with cis-LM(CO)4 (L = Bicyclo[2,2,1]hepta-2,5-dien; M = Cr, Mo, W) complexes to yield cis-substituted [R2PCH2PR2]M(CO)4 derivatives. The structure of the molybdenum compound, [(PriO)2PCH2P(OPri)2]Mo(CO)4, has been determined. Diphosphorus ligands of the type R2P(S)CH2PR2 (R = F, PriO) are monodentate and form [R2P(S)CH2PR2]2Mo(CO)4 complexes, whereas the compound (Me2N)2P(S)CH2P(NMe2)2 acts as a bidentate ligand