Diphosphiranes 3a-3f are obtained by action of diazo derivatives and carbenes on the trans-diphosphene 1. The structures are elucidated by spectroscopic methods. In all cases the cycloaddition reaction is stereoselective.
The cyclopropanation of 1 using sonochemical generation of methylene or halogeno-carbenes constitutes an interesting alternative in the diphosphirane synthesis. Furthermore, ultrasonic effects in a chlorinated solvent allow the first substitution of a diphosphirane without ring-opening.