RESUMO
Enamines are difficult to prepare on the bench due to their instability, which results in side reactions, decompositions, poor yields, etc. Herein, we developed a simple and effective method for making bench-stable enamines using a very low amount of nickel catalyst loading. The deuterium exchange, competitive reaction, and radical clock experiment have all been found to favor the ionic mechanism of this alkene isomerization. Scale-up and [3 + 2] annulation reaction of enamines with activated cyclopropane to deliver cyclopentane derivatives have shown the value of this method in organic synthesis.
RESUMO
Merging C(sp2)-H allylation and alkene difunctionalization events to access isochroman-1-imines, using N-aroyl aminoesters, MBH acetates, and NBS, under Ru(II)/Ru(IV) catalysis has been developed. Using 1H NMR, ESI-MS, HRMS, control reactions, deuterium labeling experiments, and DFT analysis, the allyl transfer (redox) process was proven to involve in C-H allylation rather than olefin insertion. Scale-up and synthetic transformations demonstrated the sustainability of this method.