Efficient kinetic resolution in the asymmetric transfer hydrogenation of 3-aryl-indanones: applications to a short synthesis of (+)-indatraline and a formal synthesis of ()-tolterodine.

Efficient kinetic resolution (KR) occurs in asymmetric transfer hydrogenation (ATH) reactions of racemic 3-aryl-1-indanones using commercial (,)- or (,)-Ts-DENEB as a catalyst, a 1 : 5 mixture of HCOH and EtN as a hydrogen source and MeOH as solvent. This process at room temperature produces near equal yields of -3-arylindanols with high dr and ee, and unreacted 3-arylindanones with excellent ee. Stereoselective transformations of 3-arylindanols and 3-arylindanones, generated by using the ATH-KR protocol, were carried out to form (+)-indatraline and synthetically valuable ()-6-methyl-4-phenylcoumarine, which is a key intermediate in the preparation of ()-tolterodine, ()-4-aryl-3,4-dihydroquinoline-2(1)-one and ()-4-aryl-3,4-dihydroisoquinoline-1(2)-one.