Ring Opening in the Hydrostannation of Methylenecyclopropanes: Effect of the Catalyst and Substrate

摘要

The generation of organometallic species by hydrometalation of carbon-carbon multiple bonds is a fundamental reaction in synthetic organic chemistry. Of particular interest in this field is the hydrostannation reaction, due to the numerous possibilities of further manipulation of the newly formed carbon-tin bond. In general, the hydrostannation of carbon--carbon multiple bonds has been achieved under radical conditions or by using transition metal catalysis. However, the methods described were foundto be unsuitable for a wide range of simple unactivated alkenes. Indeed, the reversibility of the addition of the tributyltin radical onto a carbon--carbon double bond in the absence of a stabilizing group generally restricts this reaction to activated alkenes. On the other hand, little information concerning the metal-catalyzed processes was available and essentially dealt with conjugated reductions of alkenes.