6 5 yield. A rationalization for this extraordinary behavior was that we were observing an unprecedented homoretroene (HRE) elimination of propene, where one of the silicon atoms was bypassed to achieve the six-electron process (Scheme I). The resulting disilacyclopropane, 3, 8 could now undergo the initially desired homolysis of the strained Si- Si bond, cyclize, and ring expand to the five-membered ring. Ample precedent for such a ...
