Copper-catalyzed silylation of aryl allenes using a silylborane reagent affords vinyl silane building blocks with high efficiency. The use of a seven-membered NHC ligand proved crucial for high regioselectivity. The catalytically generated allylcoppper intermediates were intercepted by aldehydes in a diastereoselective three-component coupling to furnish homoallylic alcohols.

Cu(I)-NHC-Catalyzed Silylation of Allenes: Diastereoselective Three-Component Coupling with Aldehydes. -The highly regioselective copper-catalyzed reaction of aryl allenes with silylborane (II) affords vinyl silane building blocks. The reaction can be extended to give homoallylic alcohols with high diastereoselectivity upon replacing MeOH with an aldehyde. -(RAE, J.; HU, Y. C.; PROCTER*, D. J.; Chem. -Eur. J. 20 (2014) 41, 13143-13145, http://dx.doi.org/10.1002/chem.201404330 ; Sch. Chem., Univ. Manchester, Manchester M13 9PL, UK; Eng.) -Mais 14-245