Selective Catalytic Hydrocarboxylation and Deuterocarboxylation of Allyl Cyanide to Cyanobutanoic Acids with Monodentate and Bidentate Phosphines
作者:Oriol Vallcorba、Alfonso Polo、Julio Real
DOI:10.1002/cctc.201601436
日期:2017.3.20
branched 3‐cyano‐2‐methylpropanoic acid chemo‐ and regioselectively, whereas with bidentate systems (Pd/bis[(2‐diphenylphosphino)phenyl] ether and protic acid cocatalyst) it gave linear 4‐cyanobutanoic acid chemo‐ and regioselectively. 3‐Cyano‐2‐methylpropanoic acid and 4‐cyanobutanoic acid were isolated in high yields as carboxylic acids and purified as benzyl esters. No isomerization of allyl cyanide to
用单齿膦系统(Pd /三苯膦和质子酸助催化剂)对烯丙基氰进行加氢羧化反应,可产生化学选择性和区域选择性的支链3-氰基-2-甲基丙酸,而使用双齿体系(Pd /双[(2- [2-二苯基膦基]苯基]醚和质子酸助催化剂),可以选择性地产生线性的4-氰基丁酸化学和区域选择性。3-氰基-2-甲基丙酸和4-氰基丁酸以羧酸的高收率分离,并以苄基酯的形式纯化。在任何情况下都没有观察到烯丙基氰化物异构化为巴豆腈或其羰基化衍生物。在平行实验中,相同条件下的氘代羧化反应生成相应的氘代产物,通过MS和2 H NMR光谱分析:仅d 0,d1和d 2的产品被检测到。氘进入产物的β和γ-CN位置,但未进入α位置。