Regio- and steroselective metal-mediated synthesis of polyfunctionalized

- Silyl- and stannylcupration of alkynes bearing N- or S-based functional groups takes place in a regio- and stereoselective fashion and the resulting vinyl metal species are easily quenched with a wide range of electrophiles, thereby resulting in a flexible and general route to polysubstituted silylated or stannylated olefins. For the replacement of the vinylic R3M framework in the allylic-type systems Pd(0) catalysis is needed and through Stille-type (M=Sn) or Heck-type (M=Si) reactions, the controlling factors on the regio- and stereochemistry of the synthesis of di- and trisubstituted olefins are disclosed. Conversely displacement of the R3Si group and functionalization with electrophiles at C-2 can be performed even in the absence of catalysts when N or S atoms are directly bound to the C=C moiety as part of enamino or vinylsulfide frameworks respectively