Pd-Catalyzed Oxidative Coupling of Enamides and Alkynes for Synthesis of Substituted Pyrroles
摘要:
A novel and efficient palladium(II)-catalyzed alkenyl C-H activation oxidative annulation of enamides with alkynes for the synthesis of substituted pyrroles has been developed. The reaction tolerates a wide range of functional groups and is a reliable method for the synthesis of triaryl-substituted pyrroles in high yields.
Rh(<scp>iii</scp>)-catalyzed C–H activation/cyclization of oximes with alkenes for regioselective synthesis of isoquinolines
作者:Renjie Chen、Jifeng Qi、Zhenjun Mao、Sunliang Cui
DOI:10.1039/c6ob00942e
日期:——
A Rh(III)-catalyzed C–Hactivation/cyclization of oximes and alkenes for facile and regioselective access to isoquinolines has been developed. This protocol features mild reaction conditions and easily accessible starting materials, and has been applied to the concise synthesis of moxaverine. A kinetic isotope effect study was conducted and a plausible mechanism was proposed.
An efficient copper‐promoted oxidative coupling of enamides with alkynes has been developed for the synthesis of substitutedpyrroles. The reaction proceeded through CH and NH bond functionalization of enamides under mild conditions.
A novel and efficient Fe-catalyzed radical cycloaddition of 2H-azirines and enamides for the synthesis of substituted pyrroles has been developed. The radical cycloaddition reaction proceeded through a conceptually new Fe(II)-catalyzed homolytic cleavage of C–N bond of 2H-azirines sequential radical cyclization with enamides. The reaction used readily available starting materials, tolerated various
mild diethylaminosulfur trifluoride/tetrahydrofuran (DAST–THF) system affords imidoyl fluorides. These compounds were isolated, and their structures were confirmed by X-ray single-crystal structure analysis. Reaction of imidoyl fluorides with various nucleophiles efficiently afforded amides, amidines, thioamides, and amine derivatives in high yields. Furthermore, one-pot reaction of in situ generated
用相对温和的二乙氨基三氟化硫/四氢呋喃 (DAST–THF) 系统氟化肟,得到亚氨基氟化物。这些化合物被分离出来,并通过 X 射线单晶结构分析确定了它们的结构。亚氨基氟化物与各种亲核试剂的反应有效地以高产率提供酰胺、脒、硫代酰胺和胺衍生物。此外,由肟原位生成亚氨基氟化物的一锅法反应也适用于这些产品的高效合成。肟立体化学和酸不稳定保护基在该系统中保持完整。