DUGi

Rhodium-Catalyzed [2+2+2] Cycloadditions of Diynes with Morita-Baylis-Hillman Adducts: A Stereoselective Entry to Densely Functionalized Cyclohexadiene Scaffolds

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@298533

A rhodium-catalyzed asymmetric synthesis of 5,5-disubstituted cyclohexa-1,3-dienes has been achieved by [2+2+2] cycloaddition reactions between diynes and Morita-Baylis-Hillman (M-B-H) adducts as unsaturated substrates. Products containing two adjacent chiral centres (quaternary and tertiary, respectively) were obtained with complete diastereoselectivity and high enantioselectivity (84-97%) through a kinetic resolution of the M-B-H adduct. Furthermore, these highly substituted cyclohexadienes reacted with dienophiles to afford the corresponding Diels-Alder cycloadducts in good yields

Financial support from the Spanish Ministry of Education and Science (MINECO) (Projects No.: CTQ2014-54306-P, CTQ2012-32436 and a RyC contract to A. L.) and the DIUE of the Generalitat de Catalunya (Project No.: 2014SGR931) are acknowledged

Wiley