A. Boto, R. Hernández, Y. D. de Leon
Oct 18, 2001
Citations
0
Influential Citations
34
Citations
Journal
The Journal of organic chemistry
Abstract
A new synthesis of 2,3-disubstituted pyrrolidines and piperidines is described. This mild procedure is based on the one-pot oxidative decarboxylation-beta-iodination of alpha-amino acid carbamates or amides. The iodine is introduced at the previously unfunctionalized 3-position. Different substituents can be introduced at C-2, e.g., hydroxy, alkoxy, allyl, alkyl, etc. A trans relationship between the C-2 and C-3 substituents is exclusively obtained. The influence of the solvent and the ring size of the starting amino acid are studied, as well as the nature of the protecting group on the nitrogen. The stereoselectivity of the reaction was also studied using chiral methyl (2S,4S)-4-acetyloxyproline-1-carboxylate (8). The products obtained can be manipulated to give bicyclic systems present in many natural products. By using the tandem decarboxylation-iodination-alkylation reaction, 2-substituted-3-iodopyrrolidines are formed, which are precursors of 2-substituted-2,5-dihydropyrrols.