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本文报道甲烷磺酰胺用于油菜甾体不饱和侧链的锇催化的不对称双羟化反应,结果使具有△~2化合物,例如8和12反应速度明显加快,对映选择性未受明显影.降低OsO_4及配体用量,对映选择性和反应速度明显降低.比较几种不同配体,表明两个易得的DHQD—PHN和DHQD—NAP是最好的配体 改进后的方法适宜于高立体选择性构成油菜甾体的侧链.
It has been reported that the use of methanesulfonamide for the osmium-catalyzed asymmetric dihydroxylation of steroidal side chains of rapeseed resulted in markedly faster reaction rates for compounds with Δ 2, such as 8 and 12, with enantioselectivity .Decreasing the amount of OsO 4 and the ligand, the enantioselectivity and the reaction rate were significantly reduced.Comparison of several different ligands showed that two readily available DHQD-PHN and DHQD-NAP were the best ligands. The improved method was suitable for Stereoselectively constitute the side chain of the rape steroid.