Stibasilene Sb═Si and its lighter homologues: a comparative study.

The multiply bonded derivatives of the heavier main group elements are among the most challenging targets for synthetic pursuits. Those of them featuring a double bond between the silicon and group 15 element are represented mostly by the silaimines -N═Si< and phosphasilenes -P═Si< with a very few examples of arsasilenes -As═Si<. In this contribution, we report on the synthesis and structural elucidation of the first stable stibasilene and novel phosphasilene and arsasilene derivatives, featuring an identical substitution pattern. A systematic comparison within the series phosphasilene-arsasilene-stibasilene is made on the basis of their experimental and computational studies.