Total Synthesis Without Protecting Groups: Pyrrolidines and Cyclic Carbamates
摘要:
A protecting group free synthesis of 2,3-cis substituted hydroxypyrrolidines is reported. Two novel reaction methodologies allow for the stereoselective formation of cyclic carbamates from olefinic amines, and the formation of primary amines via a Vasella/reductive amination reaction, both performed in aqueous media.
A fast, efficient and stereoselective synthesis of hydroxy-pyrrolidines
摘要:
A five-step, protecting group free synthesis of 2,3-cis substituted hydroxy-pyrrolidines is presented. Key steps in the synthesis are the chemoselective formation of a primary amine via a Vasella reductive amination using ammonia as the nitrogen source, and the stereoselective formation of a cyclic carbamate from an alkenylamine. Improvement of the reductive amination, by way of the use of alpha-picoline borane as a more environmentally benign reducing agent, is also presented. (C) 2010 Elsevier Ltd. All rights reserved.
Total Synthesis Without Protecting Groups: Pyrrolidines and Cyclic Carbamates
作者:Emma M. Dangerfield、Mattie S. M. Timmer、Bridget L. Stocker
DOI:10.1021/ol802484y
日期:2009.2.5
A protecting group free synthesis of 2,3-cis substituted hydroxypyrrolidines is reported. Two novel reaction methodologies allow for the stereoselective formation of cyclic carbamates from olefinic amines, and the formation of primary amines via a Vasella/reductive amination reaction, both performed in aqueous media.
A fast, efficient and stereoselective synthesis of hydroxy-pyrrolidines
作者:Emma M. Dangerfield、Shivali A. Gulab、Catherine H. Plunkett、Mattie S.M. Timmer、Bridget L. Stocker
DOI:10.1016/j.carres.2010.03.016
日期:2010.7
A five-step, protecting group free synthesis of 2,3-cis substituted hydroxy-pyrrolidines is presented. Key steps in the synthesis are the chemoselective formation of a primary amine via a Vasella reductive amination using ammonia as the nitrogen source, and the stereoselective formation of a cyclic carbamate from an alkenylamine. Improvement of the reductive amination, by way of the use of alpha-picoline borane as a more environmentally benign reducing agent, is also presented. (C) 2010 Elsevier Ltd. All rights reserved.