Substituent effects on the reactivity of the silicon-carbon double bond

Laser flash photolysis of various organosilicon compounds such as aryl-, vi nyl-, and alkynyldisilanes, silacyclobutanes and silacyclobutenes, and alph a -silylketenes and -diazomethanes leads to the formation of reactive silen es which can be detected directly in solution, allowing detailed studies of the kinetics and mechanisms of their reactions with nucleophiles. Over 30 transient silenes have now been studied by these methods. providing the opp ortunity to systematically assess the effects of substituents at silicon an d carbon on the reactivity of the Si=C bond.