Stereoselective reductive tetraallylation of pyridinecarboxylic acids with triallylborane
作者:Yu. N. Bubnov、E. E. Demina、V. K. Bel'sky、G. V. Zatonsky、A. V. Ignatenko
DOI:10.1007/bf02494291
日期:1998.11
Reductive tetraallylation of pyridine-3-and pyridine-4-carboxylic acids with triallylborane in the presence of propan-2-ol proceeded stereoselectively to yieldtrans-2,6-diallyl-3- andtrans-2,6-diallyl-4-(1-allyl-1-hydroxybut-3-en-1-yl)-1,2,5,6-tetrahydropyridines, respectively. Under the same conditions, the reaction with pyridine-2-carboxylic acid gave a mixture oftrans- andcis-2,6-diallyl-2-(1-a
在丙-2-醇存在下,吡啶-3-和吡啶-4-羧酸与三烯丙基硼烷的还原四烯丙基化反应立体选择性地进行,生成反式-2,6-二烯丙基-3-和反式-2,6-二烯丙基-4-(1 -allyl-1-hydroxybut-3-en-1-yl)-1,2,5,6-四氢吡啶,分别。在相同条件下,与吡啶-2-羧酸反应得到反式-和顺-2,6-二烯丙基-2-(1-烯丙基-1-羟基丁-3-烯-1-基)-1,2的混合物,5,6-四氢吡啶的比例为 57:43。当 2,6-二苯基吡啶-4-羧酸与三烯丙基硼烷反应时,只有羧基发生还原性二烯丙基化。当与三烯丙基硼烷亚二甲苯 (130–133°C, 7 h),trans-2,6-diallyl-4-(1-allyl-1-hydroxybut-3-en-1-yl)-1,2 一起加热时, 3,6-四氢吡啶转化为相应的顺式异构体。trans-2的立体化学,