Functionalization of Bis‐Diazaphospholene P–P Bonds with Diverse Electrophiles

Abstract

Phosphorus‐sp 3 or ‐sp 2 carbon bonds are readily formed by the reaction of bis‐diazaphospholenes with several classes of electrophiles. These reactions result in cleavage of the phosphorus–phosphorus bond and formation of functionalized diazaphospholenes. The reactions proceed rapidly, without catalysis. Experimental evidence with aryl and alkyl halides suggests the intermediacy of radicals in some cases, however other evidence suggests either radical or polar mechanisms may be operative for certain substrates, with a dependence on reaction conditions. In three cases, the product aryl diazaphospholenes have been shown to transfer the aryl substituent to electrophiles. These results reveal that diazaphospholene dimers are potent participants in radical chemistry with organic substrates at room temperature without requiring chemical initiators.