Cu(II)-Catalyzed Beckmann Rearrangement of Ketones

Jawahar Jat and John Falck describe the Beckmann rearrangement of ketones using copper triflate as catalyst.

Cu(OTf)2-Catalyzed Beckmann Rearrangement of Ketones Using Hydroxylamine-O-sulfonic Acid (HOSA): S. Munnuri, S. Verma, D. Chandra, R. R. Anugu, J. R. Falck, J. L. Jat

Synthesis 2019, DOI: 10.1055/s-0039-1690005

The Beckmann rearrangement is a textbook organic chemistry reaction, which – in its original version – relies on treating a carbonyl compound with hydroxylamine in strong acidic conditions at reflux, which leads to the corresponding amide through an oxime intermediate. A plethora of alternative conditions and versions of the Beckmann rearrangement have been described in the literature, but the process often requires harsh reaction conditions that limit its practicality and scope. Recently, a research collaboration between the groups of Dr. Jawahar L. Jat (Babasaheb Bhimrao Ambedkar University, Lucknow, India) and Professor John R. Falck (UT Southwestern Medical Center, Dallas, USA) resulted in a paper describing a novel, user-friendly and convenient variant of this versatile reaction.

 Dr. Jat said: “In a team effort with the group of Professor John Falck we have developed an operationally simple and one pot copper(II)-catalyzed Beckmann rearrangement of ketones under mild reaction conditions using hydroxylamine-O-sulfonic acid as aminating agent. This method provides secondary amides from ketones in good to excellent yields with wide functional group tolerance.”