Asymmetric addition of benzothiazole to N-tert-butanesulfinyl imine for the synthesis of chiral α-branched heteroaryl amines

This work concerns the asymmetric additions of benzothiazole to a variety of N-tert-butanesulfinyl imines with excellent diastereoselectivities (d.r. up to >99:1). Amino alkoxyl lithium was the key additive to obtain the excellent diastereoselectivity. More functionalized 4-methyl-5-vinyl thiazole and alkyl imines which can isomerize to enamines are also compatible substrates to the present protocol.