Enantioselective synthesis of both diastereomers including the α-alkoxy-β-hydroxy-β-methyl(phenyl) units, by chiral tin(II) Lewis acid-mediated asymmetric aldol reactions

Article abstract of DOI:10.1016/S0040-4020(01)85531-9

Diastereo- and enantioselective synthesis of both diasteromers, including the α-alkoxy-β-hydroxy-β-methyl(phenyl) units, was performed by using chiral tin(II) Lewis acid-mediated asymmetric aldol reactions of α-alkoxy silyl enol ethers with α-ketoesters. (S)-1-Propyl-2-[(1,2,3,4-tetrahydroisoquinolinyl))methyl]pyrrolidine (13), a new type of chiral diamine, was found to be effective as a chiral source in these reactions and also in the reactions of 2-(t-butyldimethylsiloxy)-1-ethylthio-1-(trimethylsiloxy)ethene (9) with aldehydes for the synthesis of optically active syn-α,β-dihydroxy thioester derivatives. (-)-2-C-Methyl-D-erythrono-1,4-lactone and (+)-2-C-methyl-L-threono-1,4-lactone were synthesized by using these reactions.