Stereoselective Domino Heck-Suzuki Reactions

Abstract

Palladium catalysis enables efficient and versatile domino reactions that are initiated by an intramolecular Mizoroki-Heck reaction and then terminated by a Suzuki-Miyaura coupling. The stereochemistry of this cascade is concerned under three aspects: Firstly, as stereoselective formation of carbon−carbon-double bonds, when the initial carbometalation occurs at an alkyne moiety. Secondly as diastereoselective and thirdly enantioselective formation of stereogenic carbon centers when the intramolecular Heck step is directed to an alkene moiety. Valuable protocols lead to – otherwise not easily accomplished – stereo control in the formation of tri- and tetra-substituted double bonds according to the first conception. The diastereoselective versions permit the formation of multiple stereocenters in mono- and polycycles. Enantioselective protocols were developed only recently. The fact that the newly created stereocenters are highly-substituted, tertiary or quaternary ones, makes the methods that are presented in this review useful and versatile tools in synthesis.