Structural requirements of a chiral ligand for the catalytic asymmetric addition of thiophenol to α,β-unsaturated esters

Abstract The tridentate amino ether ligands 1 and 14 were developed through systematic structural modification of the bidentate diether ligand 2 . The reaction of thiophenol with methyl crotonate was catalyzed by 14 and lithium thiophenolate to afford ( S )-methyl 3-phenylthiobutanoate in 75% ee and 95% yield.