Microwave-promoted tin-free iminyl radical cyclization with TEMPO trapping: a practical synthesis of 2-acylpyrroles

Org Lett. 2015 Feb 6;17(3):488-91. doi: 10.1021/ol5035047. Epub 2015 Jan 16.

Abstract

Microwave-promoted iminyl radical cyclizations can be terminated by trapping with TEMPO, affording functionalized adducts. The use of alkynes as radical acceptors delivers a range of 2-acylpyrroles in good yields. Toxic and hazardous reagents, which are frequently employed in radical reactions, are not required. The O-phenyl oxime ether substrates are constructed in a single step from readily available ketones.