Synthesis and characterization of a sulfonyland iminophosphoryl-functionalized methanide and methandiide

Abstract

The synthesis of [H2C(PPh2=NSiMe3)(SO2Ph)] (1) and its mono- and dimetalation are reported. Due to the strong anion-stabilizing abilities of the iminophosphoryl and the sulfonyl group monometalation to 1-K and dimetalation to 1-Li2 proceed smoothly with potassium hydride and methyllithium, respectively. Both compounds could be isolated in high yields and were characterized by NMR spectroscopy as well as XRD analysis. The methanide 1-K forms a coordination polymer in the solid state, while in case of the methandiide a tetrameric structure is observed. The latter features an unusual structural motif consisting of two (SO2Li)2 eight-membered rings, which are connected with each other via the methandiide carbon atoms and additional lithium atoms. With increasing metalation a contraction of the P-C-S linkage is observed, which is well in line with the increased charge at the central carbon atom and involved electrostatic interactions.