Diastereoselective Addition of Alkynylides to Michael Acceptors

Significance

Copper-catalyzed conjugate addition of carbon nucleophiles is a well-explored reaction. However, the addition of functionalized acetylides has scarcely been reported. The authors present a diastereoselective addition of a functionalized acetylide to an acceptor derived from Meldrum’s acid, yielding highly versatile compounds which can be further reacted. The use of substoichiometric amounts of copper together with alkynylides is especially noteworthy because alkynylides are known to bind as non-transferable ligands. For some of the previous work of this group on copper alkynylides, see: J. Am. Chem. Soc. 2005, 127, 9682.