Decarboxylative acylation of N-free indoles enabled by a catalytic amount of copper catalyst and liquid-assisted grinding

A facile decarboxylative acylation of N-free indoles with a-ketonates via liquid-assisted grinding was reported. The reaction requires only a catalytic amount of Cu( OAc)2 center dot H2O in combination with O2 as the terminal oxidant to give various 3-acylindoles with high efficiency. Additionally, this new methodology was applicable to a gram-scale synthesis.