Asymmetric Transfer Hydrogenation Of Linear α,β-unsaturated Ketones With BINOL-derived Boro-phosphate

Asymmetric transfer hydrogenation(ATH)has been explored rigorously in recent decades.In 2001,Japanese professor Noyori won the Nobel Prize due to the contribution in ATH reaction.This work will reveal one new application of ATH with chiral organic catalyst.Transfer hydrogenation(TH)is the prominent section of catalytic hydrogenation.The remarkable progress of transition metal catalysts in last few decades pushes TH to the real center of catalytic hydrogenation.Different metals had been successfully attempted in transfer hydrogenation,including Ir,Ru,Rh,Fe,Co,Ni and etc.In comparison,organic catalysts are also widely used in ATH reactions,but low-toxicity and easy to synthesize.The most effective organic catalyst is chiral phosphoric acids(CPAs).They has been proved in various types of reactions,including asymmetric transfer hydrogenation,but limitations still remain.To date,CPAs are most used in hydrogenation of C=N.There are only a few of literatures about hydrogenation of C=C and C=O.This project developed a methodology for asymmetric transfer hydrogenation of C=C of linear α,β-unsaturated ketones with BINOL-derived boro-phosphate.This reaction is the first of example accomplish this transformation and could give high yields(up to 99%)and enantioselectivities(up to 97%)under mild conditions.All materials,catalysts,boranes and solvents are commercial and readily accessible.Simultaneously,extensive substrate scopes and derivative reactions were also exhibited distinctly,especially the gram scale reaction.These derivatives improve the potential of this transformation for further application and exploration.