Binap catalyst doesn't dmapen expectations: In basified 2‐propanol, [RuCl2{(S)‐tol‐binap}{(R)‐dmapen}] (1, see picture, Ar=4‐CH3C6H4) catalyzes the highly enantioselective hydrogenation of a series of aryl vinyl ketones and affords the allylic alcohols in high yields with up to 98 % ee. Formation of the saturated ketones and alcohols is suppressed with triphenylphosphine when necessary.

Catalytic asymmetric hydrocyanation of a,b-unsaturated ketones into the corresponding chiral b-cyano ketones is a challenging scientific endeavor. Four major hurdles must be cleared before this reaction can be realized: 1) use of HCN as a cyanide source, [1] 2) high 1,4-addition selectivity over 1,2-addition, 3) sufficient enantioface selectivity and, 4) high catalytic activity (low catalyst loading). Recently, Shibasaki and co-workers reported pioneering studies on asymmetric 1,4-addition of cyanide to the conjugate enones catalyzed by chiral Gd and Sr compounds. [2][3][4][5] A wide range of 1,4-adducts were obtained in high enantiomeric excess (ee), but two equivalents of a tert-C 4 H 9 (CH 3 ) 2 SiCN/2,6-dimethylphenol system were required as a cyanide source to achieve the best catalyst performance.[6] Furthermore, the substrate-tocatalyst molar ratio (S/C) of 10-200 in these reactions was relatively low. [2] Our research group recently reported the asymmetric cyanation of aldehydes and a-keto esters catalyzed by our original [Ru(phgly) 2 (binap)]/Li salt systems. [7,8] The corresponding cyanated products were obtained in high ee. The spectroscopic analysis suggested that the bimetallic species [Li·Ru(phgly) 2 (binap)]+ acted as a chiral Lewis acidic catalyst. Herein, we describe the efficient asymmetric conjugate addition of HCN to a,b-unsaturated ketones catalyzed by the combined system of [Ru(phgly) 2 (binap)] and C 6 H 5 OLi. The reaction was carried out with an S/C of 200-1000 at À20-0 8C to afford the b-cyano ketones in up to 98 % ee.

Unter Basenzusatz katalysiert [RuCl2{(S)‐Tol‐binap}{(R)‐dmapen}] (1, siehe Schema, Ar=4‐CH3C6H4) in 2‐Propanol die hoch enantioselektive Hydrierung von Arylvinylketonen. Die Allylalkohole werden in guten Ausbeuten erhalten, und die Bildung gesättigter Ketone und Alkohole lässt sich durch Zugabe von Triphenylphosphan im Bedarfsfall verhindern.

Catalytic asymmetric hydrocyanation of a,b-unsaturated ketones into the corresponding chiral b-cyano ketones is a challenging scientific endeavor. Four major hurdles must be cleared before this reaction can be realized: 1) use of HCN as a cyanide source, [1] 2) high 1,4-addition selectivity over 1,2addition, 3) sufficient enantioface selectivity and, 4) high catalytic activity (low catalyst loading). Recently, Shibasaki and co-workers reported pioneering studies on asymmetric 1,4-addition of cyanide to the conjugate enones catalyzed by chiral Gd and Sr compounds. [2][3][4][5] A wide range of 1,4-adducts were obtained in high enantiomeric excess (ee), but two equivalents of a tert-C 4 H 9 (CH 3 ) 2 SiCN/2,6-dimethylphenol system were required as a cyanide source to achieve the best catalyst performance. [6] Furthermore, the substrate-tocatalyst molar ratio (S/C) of 10-200 in these reactions was relatively low. [2] Our research group recently reported the asymmetric cyanation of aldehydes and a-keto esters catalyzed by our original [Ru(phgly) 2 (binap)]/Li salt systems. [7,8] The corresponding cyanated products were obtained in high ee. The spectroscopic analysis suggested that the bimetallic species [Li·Ru(phgly) 2 (binap)] + acted as a chiral Lewis acidic catalyst. Herein, we describe the efficient asymmetric conjugate addition of HCN to a,b-unsaturated ketones catalyzed by the combined system of [Ru(phgly) 2 (binap)] and C 6 H 5 OLi. The reaction was carried out with an S/C of 200-1000 at À20-0 8C to afford the b-cyano ketones in up to 98 % ee.

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