The synthesis of alkenes from carbonyl compounds and carbanions alpha to silicon. III. A full report and a synthesis of the sex pheromone of gypsy moth

Aza-Peterson Olefinations: Rapid Synthesis of (E)-Alkenes

An aza-Peterson olefination methodology to access 1,3-dienes and stilbene derivatives from the corresponding allyl- or benzyltrimethylsilane is described. Silanes can be deprotonated using Schlosser’s base and added to N-phenyl imines or ketones to directly give the desired products in high yields.

Silicon-Mediated Organic Synthesis

Organic chemists have used the chemical properties of tetracovalent silicon in a remarkable variety of new synthetic transformations. In carbon-functional silanes, exceptional stabilization is provided to a carbocation center in the beta position when the carbon-silicon bond lies in plane. This phenomenon directs electrophilic attack to the silicon-substituted carbon in aryl-, vinyl-, and alkynylsilanes and to carbon-3 in allylsilanes. For different reasons, silicon also stabilizes a carbon-metal bond in the alpha position. Consequently, access to many silicon-containing organometallics is readily available. The exceptional strength of silicon-oxygen and silicon-fluorine bonds is yet another factor that controls the chemical reactivity of silicon reagents. In recent developments, preparative chemists have taken advantage of these properties in imaginative and useful ways.