Photochemical rearrangement of N-chlorolactams: a route to N-heterocycles through concerted ring contraction.
We report a novel ring contraction allowing the direct conversion of N-chlorolactams to their corresponding ring-contraction N-heterocycles upon photolysis. Results show that the rearrangement occurs with a variety of N-chlorolactams and that the greater the substitution at the migrating carbon, the greater the yield of product. Importantly, stereochemistry at the migrating carbon is conserved in the product. Rearranged products were isolated as their methyl carbamates in yields varying from 17% to 58%, with the major side product being the recyclable parent lactam.
Winter
Dana K
DK
Département de Chimie, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1.
Drouin
Alexandre
A
Lessard
Jean
J
Spino
Claude
C
D007769:Lactams / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D055668:Photochemical Processes
D007769:Lactams; D009584:Nitrogen