Palladium-Catalyzed Asymmetric Reduction of Racemic Allylic Esters with Formic Acid: Effects of Phosphine Ligands on Isomerization of π-Allylpalladium Intermediates and Enantioselectivity
作者:Motoi Kawatsura、Yasuhiro Uozumi、Masamichi Ogasawara、Tamio Hayashi
DOI:10.1016/s0040-4020(99)01107-2
日期:2000.4
A new MOP ligand (1b), (R)-(+)-2-(bis(3-trifluoromethylphenyl)phosphino)-2′-methoxy-1,1′-binaphthyl, was found to be more enantioselective than other MOP ligands for the palladium-catalyzed asymmetric reduction of α,α-disubstituted allylic esters with formic acid. The reduction of dl-2-(1-naphthyl)-3-buten-2-yl benzoate gave 3-(1-naphthyl)-1-butene of 90% ee. The higher enantioselectivity of 1b is
发现一种新的MOP配体(1b)(R)-(+)-2-(双(3-三氟甲基苯基)膦基)-2'-甲氧基-1,1'-联萘基比其他MOP配体对映选择性更高用甲酸催化钯催化α,α-二取代的烯丙基酯的不对称还原。还原苯甲酸dl-2-(1-萘基)-3-丁烯-2-基酯得到90%ee的3-(1-萘基)-1-丁烯。的对映体选择性高1B是归因于快速顺-反通过氧化加成烯丙基酯与钯(0)物种形成π烯丙基钯中间体的异构化。的速率顺-反异构化是通过在磁化饱和转移测定11 H NMR。