Investigations of Doubly Connected Phosphorus Cations. Diaminophosphenium Ions from 2-R-2-Phospha-1,3-diazacycIohexanes

Abstract

Mass spectral analysisof a series of N,N′-dimethyl-2-R-2-phospha-1,3-diazacyclohexanes (R = Cl, OCH3, CH3, C2H5,C6H5) reveals a primary fragmentation pathway affording loss of the phosphorus R group and generation of a divalent phosphenium species as the major (base) fragment. Diequatorial orientation of the N-alkyl groups is important to stabilization of the cations, as deduced from the failure of certain bicyclic derivatives to provide phosphenium ions when the iV-alkyl groups are locked in axial positions. Treatment of 2-chloro-2-phospha-1,3-diazacyclohexanes with PCU gave an ionic species which is best interpreted (pmr, 31P nmr, conductance measurements) in terms of a doubly connected phosphorus cation salt. © 1972, American Chemical Society. All rights reserved.