A Novel Method for the Synthesis of Polycyclic Phosphorus Chalcogenides

Abstract

With pyridine as activating solvent and depolymerization catalyst and tris(trimethylsilylchalcogeno)phosphane P(ESiMe₃)₃ (E: S (la), Se (lb)), we succeeded in synthesizing α-[P₄E₇]M₂ (M: [Me₃Si-NC₅H₅]⁺; E: S (2a), Se (2b)), the first bicycles consisting of phosphorus chalcogen anions with a norbornane skeleton. The constitution of (2a, 2b) was determined by the analysis of their ¹H-, ³¹P- and ⁷⁷Se-nmr spectra. By variation of the reaction conditions, two P₆-suliiir-heterocycles are obtained as the mam products. The³¹P-nmr spectrum indicates two isomers of P₆S₇M₂ (3a, 4a) with a tricyclic structure related to the hydrocarbon brexan. In addition, the reactions of tBuP(ESiMe₃)₂ (E: S (5a), Se (5b)) in pyridine are reported.