Phosphinidene Addition to Conjugated Allenes

Abstract

Generating the transient electrophilic tungsten pentacarbonyl-phenylphosphinidene complex PhP=W(CO) 5 in the presence of 2,7-dimethylocta-2,3,5,6-tetraene leads to the formation of a 3,4-di-A C H T U N G T R E N N U N G substituted phosphole or a complexed phospholene, depending on the reaction conditions. The formation of the phospholene results from the reaction of PhP=W(CO) 5 with the diallene, while the formation of the phosphole arises from reaction with 3,4-diisopropylidene-cyclobutene, which is formed in situ from the isomerization of the conjugated allene.

The chemistry of bisallenes

“…For example, the tungsten-complexed pentacarbonyl complex PhP=W(CO) 5 , generated by heating 191 (retro-Diels–Alder reaction), provided the unexpected 3,4-disubstituted phosphole 192 (Scheme 45) [133]. Analogously, the phospholene complex 194 resulted from heating 24 and 193 together [134].…”