[reaction: see text] A practical method for the synthesis of opticallyactive styrene oxides has been developed via formation of opticallyactive 2-chloro-1-phenylethanols generated by reductive transformation of ring-substituted 2-chloroacetophenones. The opticallyactive alcohols with up to 98% ee are obtainable from the asymmetric reduction of acetophenones with an S/C = 1000-5000 with a formic
[反应:见正文]通过形成由环取代的2-氯苯乙酮的还原转化而生成的光学活性的2-氯-1-苯基乙醇,已经开发了一种合成光学活性的苯乙烯氧化物的实用方法。ee高达98%的旋光性醇可通过将S / C = 1000-5000的苯乙酮与含有明确定义的手性Rh络合物CpRhCl [(R,R)- tsdpen]。
A practical synthesis of optically active aromatic epoxides via asymmetric transfer hydrogenation of α-chlorinated ketones with chiral rhodium–diamine catalyst
A practical method for the synthesis of optically active aromatic epoxides has been developed via the formation of optically active α-chlorinated alcohols and intramolecular etherification. Optically active alcohols with up to 99% ee can be obtained from the asymmetric reduction of aromaticketones with a substrate/catalyst ratio of 1000–5000 using a formic acid/triethylamine mixture containing a well-defined
Asymmetric hydrogenation of various alpha-chloro aromatic ketones with Ru(OTf)(TsDPEN)(eta(6)-arene) (TsDPEN = N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine) produces the chiral chlorohydrins in up to 98% ee. This reaction can be conducted even on a 206-g scale. The hydrogenation of an alpha-chloro ketone with a phenol moiety has been utilized for the synthesis of (R)-norphenylephrine without protection-deprotection operations.