Catalytic Asymmetric Synthesis of Epoxides from Aldehydes Using Sulfur Ylides with In Situ Generation of Diazocompounds
作者:Varinder K. Aggarwal、Emma Alonso、George Hynd、Kevin M. Lydon、Matthew J. Palmer、Marina Porcelloni、John R. Studley
DOI:10.1002/1521-3773(20010417)40:8<1430::aid-anie1430>3.0.co;2-w
日期:2001.4.17
absolute stereochemistry has been achieved by generating the reactive intermediate (the diazo compound) in situ from tosylhydrazone salts (see scheme, PTC=phase-transfer catalyst, Ts=toluene-4-sulfonyl). High yields (58-82 %), high d.r. (88:12-98:2), and high ee values (87-94 %) have been obtained using a new class of stable chiral sulfides at low catalyst loading (5 mol %) and [Rh2 (OAc)4 ] (0.5 mol %).
通过从甲苯磺酰salts盐原位生成反应性中间体(重氮化合物),已实现了控制相对和绝对立体化学的实用,通用且收敛的环氧化物途径(参见方案,PTC =相转移催化剂,Ts =甲苯) -4-磺酰基)。使用新型的稳定的手性硫化物,在低催化剂负载量(5 mol%)下,已获得高产率(58-82%),高dr(88:12-98:2)和高ee值(87-94%) )和[Rh 2(OAc)4 ](0.5摩尔%)。