Aminocarbonylation of alkenyl iodides with CO and amines proceeded under heating to produce α,β-unsaturatedamides in good yields (23 examples, 71% average yield). This catalyst-free method exhibited good functional-group tolerance, and open a straightforward access to functionalized acrylamides, as illustrated by the synthesis of Ilepcimide. A hybrid radical/ionic mechanism involving chain electron transfer is
烯基碘与 CO 和胺的氨基羰基化在加热下进行,以良好的产率(23 个实例,71% 的平均产率)产生 α,β-不饱和酰胺。这种无催化剂的方法表现出良好的官能团耐受性,并打开了对官能化丙烯酰胺的直接访问,如 Ilepcimide 的合成所示。针对这种转变提出了一种涉及链式电子转移的混合自由基/离子机制。
CrCl<sub>2</sub>-Promoted Stereospecific and Stereoselective Alkyl- and Silylcyclopropanation of α,β-Unsaturated Amides
作者:José M. Concellón、Humberto Rodríguez-Solla、Carmen Méjica、Elena G. Blanco、Santiago García-Granda、M. Rosario Díaz
DOI:10.1021/jo800103t
日期:2008.5.1
An efficient chromium-promoted alkyl- or silylcyclopropanation of α,β-unsaturated amides is described. These reactions can be carried out on (E)- or (Z)-α,β-enamides in which the C−C double bond is di-, or trisubstituted. This process takes place with totalstereospecificity and the new stereogenic center is generated with high or total stereoselectivity. Some synthetic applications of the obtained
Highly Stereoselective Halocyclopropanation of α,β-Unsaturated Amides
作者:José M. Concellón、Humberto Rodríguez-Solla、Elena G. Blanco、María A. Villa-García、Noemí Alvaredo、Santiago García-Granda、M. Rosario Díaz
DOI:10.1002/adsc.200900331
日期:2009.9
A convenient highly stereoselective synthesis of chloro- and bromocyclopropanamides from di- tri- or tetrasubstituted (E)- or (Z)-α,β-unsaturatedamides with total or high stereoselectivity promoted by chromium dichloride or dibromide is described. The transformation of chlorocyclopropanamides into the corresponding ketones or amines is also reported. A mechanism to explain these transformations is
An Efficient Catalytic Chromium-Mediated Iodocyclopropanation Reaction: Stereoselective Synthesis of Iodocyclopropanecarboxamides
作者:José M. Concellón、Humberto Rodríguez-Solla、Elena G. Blanco、Santiago García-Granda、and M. Rosario Díaz
DOI:10.1002/adsc.201000574
日期:2011.1.10
catalytic chromium‐mediated novel synthesis of iodocyclopropanecarboxamides is reported. This reaction can be carried out on aromatic (E)‐ or (Z)‐α,β‐unsaturated amides in which the CC double bond is di‐ or trisubstituted. This process takes place with total stereospecificity and the new CI stereogenic center is generated with high stereoselectivity. Some synthetic applications of the obtained iodocyclopropanecarboxamides