Polydentate Ligands Containing Phosphorus, III [1]. Synthesis and Nuclear Magnetic Resonance Studies of Some Unsymmetrical Potentially Tridentate Phosphine Chalcogenide Ligands

Abstract

The synthesis via the useful lithium reagent intermediate, (C₆H₅)₂P(S)CH₂Li, is reported for eight compounds of the type [(C₆H₅)₂P(X)][R₂P(X)]₂CH, where R is methyl or phenyl and X is an electron pair, oxygen, or sulfur in various combinations. Two related compounds with three and four phosphorus atoms, respectively, per molecule have also been prepared from the same lithium reagent. Tris(diphenylthiophosphoryl)methane has three equivalent phosphorus atoms as indicated by the room temperature phosphorus-31 NMR spectrum, but at reduced temperature a favored conformation exists which has two equivalent phosphorus atoms and a unique one. Other phosphorus-31 and proton NMR data are reported