Addition of a Phenyl Phosphinidene Complex to Conjugated Diynes

Abstract

Alkynyl-substituted phosphirenes are formed from the addition of PhPW(CO)5 to 2,4-hexadiyne, 5,7-dodecadiyne, and 2,2,7,7-tetramethylocta-3,5-diyne. No bisphosphirenes are formed. Instead, but only for the 2,4-hexadiyne derivative, a second PhPW(CO)5 inserts into the phosphirene ring to give a 2:1 mixture of cis- and trans-1,2-dihydro-1,2-diphosphetes. An X-ray structure determination, ab initio computed geometries, and NMR data are presented.