ChemInform Abstract: Radical Cyclizations Promoted by Dimanganese Decacarbonyl: A New and Flexible Approach to 5‐Membered N‐Heterocycles.

Abstract

Radical Cyclizations Promoted by Dimanganese Decacarbonyl: A New and Flexible Approach to 5-Membered N-Heterocycles. -Irradiation of dimanganese decacarbonyl generates a manganese carbonyl radical, which causes cyclization of haloethanamides such as (I) to give the pyrrolidinone (II). The radical produced by cyclization can be trapped by isopropanol to give the pyrrolidinone (III). Interestingly, the presence of TEMPO (V) gives the trapping product (VI) of the initial carbamoyl radical, whereas slow addition of (V) leads to trapping of the cyclized radical. -(GILBERT, BRUCE C.; KALZ, WILHELM; LINDSAY, CHRIS I.; MCGRAIL, TERRY P.; PARSONS, ANDREW F.; WHITTAKER, DAVID T. E.; Tetrahedron Lett. 40 (1999) 33, 6095-6098; Dep. Chem., Univ. York, Heslington, York YO10 5DD, UK; EN)