Kinetic Resolution of Activated Nitroallylic Acetates with Aldehydes and Ketones through a Conjugate Addition-Elimination SN2′ Process
作者:Raju Jannapu Reddy、Pei-Hsun Lee、Dhananjay R. Magar、Jung-Hsuan Chen、Kwunmin Chen
DOI:10.1002/ejoc.201101162
日期:2012.1
A unique organocatalytic kineticresolution (KR) of nitroallylicacetates has been developed. A variety of racemic nitroallylicacetates (1a–n) were resolved with chiral enamines formed in situ from the reaction of aldehydes and ketones with organocatalyst 2b (2.5 mol-%) and 14c (20 mol-%), respectively, through an interesting SN2′ reaction. The densely functionalized products 3–5 were obtained with
Highly Efficient Organocatalytic Kinetic Resolution of Activated Nitroallylic Acetates with Aldehydes via Conjugate Addition−Elimination
作者:Raju Jannapu Reddy、Kwunmin Chen
DOI:10.1021/ol200133y
日期:2011.3.18
A novel, efficient, and unprecedented organocatalytic kineticresolution has been developed. For the first time, a variety of nitroallylicacetates 1a−i have been resolved with aldehydes in the presence of 2 (2.5 mol %) via conjugateaddition−elimination. The densely functionalized products 3a−o were obtained with excellent enantioselectivities (up to >99% ee), and unreacted substrates 1a−i were recovered