A Chiral Heterobimetallic ZABDP Complex For Catalytic Asymmetric Aldol Reaction Of Aryl Ketones To Aryl Aldehydes

The Aldol reaction is one of the most important carbon-carbon bond formation reactions in organic chemistry, because it can produce versatileβ-hydroxyl carbonyl compounds, which are key intermediates or synthetic building blocks of biologically active compounds. According to the catalytic mechanism of Aldose, many groups are now focusing on designing chiral bimetal catalysts for asymmetric direct aldol reactions. Although there are many bimetal catalysts for asymmetric direct aldol reaction have been designed, it is also a challenging issue for direct reaction of aryl ketones with aryl aldehydes.Direct asymmetric aldol reaction between aryl ketones and aryl aldehydes catalyzed by chiral organometallic complexes has not been reported except our research group reported bimetal Zn catalyst ZZBDP, but the result is not very satisfactory. So our team are focusing on designing new organometallic complexes for such reaction.Herein we report our new designed heterobimetal catalyst ZABDP for the direct asymmetric aldol reaction of aryl ketones with aryl aldehydes for the first time. Ligands 53 were designed and synthesized from chiral BINOL and (S)-diphenylprolinol and then ligands with znic and aluminium design heterobimetal catalysts in situ, for direct asymmetric aldol reaction between aryl ketones and aryl aldehydes, and the results is the best one in such reaction. Up to 99% yield and up to 90% enantioselectivity were achieved. It is not only enriched heterobimetal catalysts for direct asymmetric aldol reaction, but also use aluminium and zinc as cooperator for the first time. As aluminium is the most abundant metal on the earth, it will lead us to use aluminium instead of transition metal, rare metal and some precious metal for organometallic catalysts.