Asymmetric Synthesis of (1,3-Butadien-2-yl)methanols from Aldehydes via [1-(Silylmethyl)allenyl]methanols
作者:María Durán-Galván、Brian T. Connell
DOI:10.1002/ejoc.201000199
日期:2010.5
[1-(Silylmethyl)allenyl]methanols 2 were efficiently synthesized from aldehydes and (4-bromobut-2-ynyl)trimethylsilane in the presence of a catalytic amount of CrCl 2 and tridentate carbazole ligands. The desired compounds were obtained with good yields (43-88%) and enantioselectivities (55-78 % ee). Alcohols 2 may be treated with TBAF or 2 M HCl in the case of aliphatic substrates, to provide (1,
在催化量的 CrCl 2 和三齿咔唑配体存在下,[1-(甲硅烷基甲基)烯基]甲醇 2 由醛和 (4-溴丁-2-炔基)三甲基硅烷有效合成。以良好的产率 (43-88%) 和对映选择性 (55-78% ee) 获得所需化合物。在脂肪族底物的情况下,醇2可以用TBAF或2M HCl处理,以43-81%的产率提供(1,3-丁二烯-2-基)甲醇3。这种方法允许合成二烯 3 没有区域选择性问题,并且它可以容忍大量的功能。