title: Highly chemoselective Baylis-Hillman and aldol reactions of 2H-thiopyran-4(3H)-one using tertiary amine catalysts in aqueous media.
abstract: For the first time, the Baylis-Hillman (BH) reaction of 2H-thiopyran-4(3H)-one is investigated, and surprisingly, the reaction of 2H-thiopyran-4(3H)-one with aldehydes in the presence of different tertiary amines shows excellent chemo- and regioselectivity in water. At room temperature, DBU affords BH adducts, but with DABCO, aldol products were obtained. In the case of DABCO, Et(3)N, or DMAP, domino aldol-rearrangement reactions occurred at 45-50 °C.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Maragheh, Golshar, P.O. Box. 55181-83111, Maragheh, Iran. eftekharisis@maragheh.ac.ir
authors.forename: Bagher
authors.initials: B
authors.lastname: Eftekhari-Sis
authors.forename: Ali
authors.initials: A
authors.lastname: Akbari
authors.forename: Klaus
authors.initials: K
authors.lastname: Harms