RuCl2[S-BINAP]-catalyzed synthesis of aldehydes and ketones by dehydrogenation of alcohols

RuCl 2 [ S -BINAP] catalyzed dehydrogenation of alcohols into aldehydes or ketones has been investigated. Among many H-acceptors screened, diphenylacetylene (tolane) was the most suitable judged from its smooth reduction. Electron rich and deficient analogues of tolane have been synthesized. Based on competition experiments between these H-acceptors a tentative catalytic cycle for the RuCl 2 [ S -BINAP] catalyzed dehydrogenations is proposed.