Polysubstituted oxygen heterocycles by a Reformatsky-type reaction/reductive cyclization approach from enantiopure beta-ketosulfoxides.
The stereoselective synthesis of tetrasubstituted tetrahydrofurans and trisubstituted tetrahydropyrans bearing a sulfoxide was achieved by reductive cyclization (Et3SiH/TMSOTf) from the corresponding enantiopure hydroxy ketones protected as a dioxolane. These derivatives are easily accessible from a Reformatsky-type reaction between alpha-bromo-alpha'-sulfinyl ketones and protected alpha- or beta-ketoaldehydes, followed by diastereoselective reduction of the resulting beta-ketosulfoxide.
Colobert
Françoise
F
Laboratoire de Stéréochimie associé au CNRS, UMR 7509, Université Louis Pasteur, ECPM 25 rue Becquerel, 67087 Strasbourg Cedex 2, France. fcolober@chimie.u-strasbg.fr
Choppin
Sabine
S
Ferreiro-Mederos
Leticia
L
Obringer
Michel
M
Arratta
Sandra Luengo
SL
Urbano
Antonio
A
Carreño
M Carmen
MC