Synthesis of Allene Substituted Nipecotic Acids by Allenylation of Terminal Alkynes
作者:Maren Schaarschmidt、Klaus T. Wanner
DOI:10.1021/acs.joc.7b00630
日期:2017.8.18
several secondary amines serving as hydride donors in propargylic amines undergoing a [1,5]-hydride transfer reaction to yield the respective terminal and 1,3-disubstituted allenes were studied. For this study, a two-step procedure was employed. At first, the synthesis of propargylic amines via the CuI-catalyzed aldehyde-alkyne-amine reactions (A3 coupling) was accomplished. The obtained propargylic amines
研究了进行[1,5]-氢化物转移反应生成相应的末端和1,3-二取代的烯丙基的炔丙基胺中用作氢化物供体的几种仲胺的相对反应性。对于本研究,采用了两步程序。首先,通过Cu I催化的醛-炔-胺反应(A 3偶联)完成了炔丙基胺的合成。随后将获得的炔丙基胺在CdI 2或ZnI 2催化下转化为所需的烯丙基。结果,在所使用的各种仲胺中,在空间体积,电子性质和构象性质方面不同,烯丙基(叔)发现叔丁基胺是合成末端亚丙基的最佳氢化物供体。为了合成1,3-二取代的烯,在炔丙基位置含有烯丙基(叔丁基)胺或1,2,3,6-四氢吡啶单元的丙炔衍生物表现最佳。最后,通过改进的方法,使用ZnI 2作为催化剂来制备1-取代的CdI 2或CdI 2来合成1,3-二取代的烯,以高收率合成了含有N-烯基取代基的庚二酸衍生物。