A Rare Example of a Rearrangement Involving Four Structural Isomers: #alpha#-Phosphinonitrile/C-Phosphinoketenimine/1-Aza-4-phosphabutadiene/1,2-Dihydro-1,2-azaphosphete

摘要

The stable compound [bis(dicyclohexylamino)phosphino](trimethylsilyl)carbene(1) reacts with dimethyl cyanamide to afford the original 1,2-dihydro-1,2-azaphosphete 4a (51% yield). The surprising formation of this heterocycle involves the transient formation of a nitrile, a keteneimine, and a 1-aza-4#lambda#-phosphabutadiene derivative. By using substituent effects and different synthetic routes, all of these structural isomers have been isolated.