ChemInform Abstract: Synthesis of Novel β‐Amino Alcohols and Their Application in the Catalytic Asymmetric Sulfoxidation of Sulfides.

Abstract

Abstract Novel chiral norephedrine-based β-amino alcohol ligands containing a thiophene ring were prepared from norephedrine and substituted furan carbaldehydes (methyl- or ethyl-substituted) and used in combination with VO(acac) 2 for the asymmetric oxidation of aryl methyl sulfides using H 2 O 2 as an oxidant. Amino alcohol derived Schiff bases 4 , 5a – b gave higher enantiomeric excesses than amino alcohol-derived reduced Schiff based ligands 6 , 7a – b . Of these chiral ligands, (1 S ,2 R )- 5b and (1 S ,2 R )- 7b gave high yields (90%) with moderate to high enantioselectivities (78%, 96% ee, respectively). The oxidation of other aryl methyl sulfides with (1 S ,2 R )- 5b and (1 S ,2 R )- 7b as ligands afforded the corresponding sulfoxides in 60–89% yields and with 92–99% ee.