Reaction of lithium diphenylphosphide, diphenylarsenide, and diphenylstibide with 1,2-dichloroethylenes. The preparation of some new bidentate ligands and their monosubstituted precursors

Abstract

Contrary to previous work, lithium diphenylarsenide reacts with trans-1,2-dichloroethylene to produce trans-1,2-bis(diphenylarsino)ethylene. Lithium diphenylarsenide also reacts with excess of cis- or trans-1,2-dichloroethylene at 0 °C to yield the corresponding (2chlorovinyl)diphenylarsine stereospecifically, but only the l,2-bis(diphenylphosphino) ethylenes have been obtained under analogous conditions using lithium diphenylphosphide. The cis- and trans-(2-chlorovinyl)diphenylarsine also react stereospecifically with Li[PPh₂] to yield cis-and trans-1-diphenylarsino-2-diphenylphosphinoethylene in high yield. cis-(2-Chlorovinyl)diphenylarstne and sodium dimethylarsenide yield only cis-1 -dimethylarsino-2-diphenylarsinoethylene, in contrast to the reaction of the latter with cis-1,2-dichloroethylene when both cis- and trans-1,2-bis(dimethylarsino)ethylene result. The preparation of 1-diphenylarsino-2-diphenylphosphinoethane, and the reactions of sodium diphenylstibide with cis- and trans-1,2-dichioroethylene, are also described.