Bismuth‐Mediated Diastereoselective Allylation Reaction of Carbonyl Compounds with Cyclic Allylic Halides or Cinnamyl Halide
作者:Xuan‐Yu Liu、Bu‐Qing Cheng、Yi‐Cong Guo、Xue‐Qiang Chu、Yong‐Xin Li、Teck‐Peng Loh、Zhi‐Liang Shen
DOI:10.1002/adsc.201801297
日期:2019.2
homoallylic alcohols in good to excellent yields with high diastereoselectivities (>99:1 dr). Reversed diastereoselectivity was obtained when carbonyl substrate (e. g., 2‐pyridinecarboxaldehyde, glyoxylic acid) containing chelating substituent was used in the allylation reaction. In addition, the reactions involving acyclic (E)‐cinnamyl bromide as substrate worked equally well with high diastereocontrol.
通过在LiI存在下使用可商购的铋粉,开发了各种羰基化合物与环状烯丙基卤化物的有效非对映选择性烯丙基化。在所有被筛选的金属中,铋被认为是转化的最佳介体。涉及各种环状烯丙基卤化物的反应在室温下顺利进行,以高至非对映异构体选择性(> 99:1 dr)的高收率或优良收率生产出所需的均丁醇。当在烯丙基化反应中使用含有螯合取代基的羰基底物(例如2-吡啶羧甲醛,乙醛酸)时,获得了反向的非对映选择性。此外,以非环(E)-肉桂基溴为底物的反应在非对映异构控制较高的情况下也能很好地发挥作用。