4,5-Dioxo-imidazolinium Cation Activation of 1-Acyl-1-carbamoyl Oximes: Access to Cyanoformamides Using Dichloroimidazolidinedione.

Cyanoformamides are prevalent as versatile building blocks for accessing synthetically useful intermediates and biologically active compounds. The development of a milder, simpler, and more efficient approach to cyanoformamides is nontrivial. Herein, we demonstrate the effectiveness of 4,5-dioxo-imidazolinium cation activation for transforming 1-acyl-1-carbamoyl oximes to cyanoformamides.

Dichloroimidazolidinedione-Activated Beckmann Rearrangement of Ketoximes for Accessing Amides and Lactams.

A novel protocol for the activation of the Beckmann rearrangement utilizing the readily available and economical geminal dichloroimidazolidinediones (DCIDs) on a substoichiometric scale (10 mol %) has been developed. A unique self-propagating mechanism for the substoichiometric dichloroimidazolidinedione-activated transformation was proposed and validated. The substrate scope of the developed protocol has been demonstrated by 23 examples with good to excellent yields (mostly 90-98%) in a short time (mostly 10-30 min), including a substrate for synthesizing the monomer of nylon-12 and a complicated steroidal substrate on a preparative scale.