title: Zinc(II)-catalyzed intermolecular hydrative aldol reactions of 2-en-1-ynamides with aldehydes and water to form branched aldol products regio- and stereoselectively.
abstract: This work describes zinc(II)-catalyzed hydrative aldol reactions of 2-en-1-ynamides with aldehydes and water to afford branched aldol products regio- and stereoselectively. The anti and syn selectivity can be modulated by the sizes of sulfonamides to yield E- and Z-configured zinc(II) dienolates selectively. This new reaction leads to enantiopure aldol products by using a cheap chiral sulfonamide. The mechanistic analysis reveals that the sulfonamide amides of the substrates can trap a released proton to generate dual acidic sites to activate a carbonyl allylation reaction.
authors.affiliation: Department of Chemistry, National Tsing-Hua University, Hsinchu, 30043, Taiwan (ROC).
authors.forename: Appaso Mahadev
authors.initials: AM
authors.lastname: Jadhav
authors.forename: Vinayak Vishnu
authors.initials: VV
authors.lastname: Pagar
authors.forename: Deepak B
authors.initials: DB
authors.lastname: Huple
authors.forename: Rai-Shung
authors.initials: RS
authors.lastname: Liu
keywords: aldol reaction; stereoselectivity; sulfonamides; synthetic methods; zinc