Insight into the Metal‐Free Reduction of Isocyanates to <i>N</i>‐Methyl Anilines at Room Temperature

A simple and sustainable protocol has been developed to reduce isocyanates to the N-methyl anilines under metal-free conditions. The reaction proceeds with BF₃ ⋅ OEt₂ as a catalyst and ammonia borane as a hydrogen source in THF at room temperature, leading to the formation of a wide range of substituted aniline derivatives. Control experiments and deuterium labeling studies were performed to understand the mechanism of the present procedure. A detailed computational study was also conducted to shed light on the possible mechanism and free energies of the intermediates and transition states involved in this present protocol.