Thioacids mediated selective and mild N-acylation of amines.

N-Acylated amines are ubiquitous in nature. Selective N-acylation at neutral conditions remains a key area of interest. Here we are reporting the copper sulfate-mediated highly selective, mild, and rapid N-acylation of various aliphatic and aromatic amines using thioacids in methanol at neutral conditions. All N-acylated products of primary and secondary amines were isolated in good to excellent yields. This method is found to be highly selective for the amines and not sensitive to other functional groups such as phenols, alcohols, and thiols. The simple workup, high yields, and high selectivity of this reaction can be an attractive alternative to those of the existing acyl halide- and acid anhydride-mediated N-acylation reactions.