Enantioselective elimination reaction of a 6,6-membered bicyclic allylic carbonate. Importance of chirality reversal depending on the palladium-chiral phosphine ratio
作者:Isao Shimizu、Yoshiyuki Matsumoto、Ken Shoji、Toshiya Ono、Akiharu Satake、Akio Yamamoto
DOI:10.1016/0040-4039(96)01587-0
日期:1996.9
Reaction of (±)-8α-methoxycarbonyloxy-4aβ-methyl-2,3,4,4a,5,6,7,8-octahydronaphthalene (1) in the presence of a palladium-chiral phosphine catalyst gave 4a-methyl-3,4,4a,5,6,7-hexahydronaphthalene (2) enantioselectively. When the reaction was carried out using Pd(OAc)2 and (S)-(−)-BINAP, the enantioselection was influenced by the phosphine to palladium ratio, because (S)-BINAP oxide generated in situ
(±)-8α-甲氧基羰氧基-4aβ-甲基-2,3,4,4a,5,6,7,8-八氢萘(1)在钯-手性膦催化剂的存在下反应得到4a-甲基-3对映选择性地为4,4a,5,6,7-六氢萘(2)。当使用Pd(OAc)2和(S)-(-)-BINAP进行反应时,对映体的选择受膦与钯之比的影响,因为原位生成的(S)-BINAP氧化物充当配体,导致相反的对映选择性。当(1-Me-C 3 H 5 -PdCl)2和(S)-(-)- p时,获得高对映选择性(86%ee)-Tol-BINAP被使用。