The asymmetric addition of pyridyl aluminum reagents to aldehydes has been successfully developed by employing a titanium(IV) catalytic system of (R)-H-8-BINOLate, which affords a series of valuable optically active diarylmethanols containing various pyridyl groups in high yields with excellent enantioselectivities of up to 98% ee.
Asymmetric Transfer Hydrogenation of Densely Functionalized Diheteroaryl and Diaryl Ketones by a Ru-Catalyst of Minimal Stereogenicity
functionalized diheteroaryl and diaryl ketones was developed using Ru-catalysts of minimal stereogenicity. Various ketone substrates with structurally and electronically similar groups attached to the prochiral centers were reduced successfully in good to excellent enantioselectivities and yields. This protocol provides practical and efficient access to chiral diheteroarylmethanols and benzhydrols,