Regiospecific and Stereoselective Synthesis of Functionalized and Differently Metalated Alkenes by Silyl- or Stannylcupration of Metalated Acetylenes

Differently metalated vinylcuprate intermediates resulting from silyl- or stannylcupration of silyl- and tin-containing acetylenes reacted with a range of electrophiles, including chlorosilanes and chlorostannanes, affording regio- and stereodefined differently metalated vic and gem silyl- and tin-trisubstituted alkenes. Some of these functionalized polymetalated olefins are interesting synthons in organic chemistry.