CsOH-promoted chemoselective mono-N-alkylation of diamines and polyamines
摘要:
Selective N-alkylation of diamines and polyamines was carried out using cesium hydroxide, 4 Angstrom molecular sieves, and DMF. This protocol was highly chemoselective, favoring mono-N-alkylation over overalkylations. (C) 2000 Published by Elsevier Science Ltd.
beta-Aminoalcohols were smoothly converted to beta-amino bromides using thionyl bromide and DME which were easily isolated without any further purification. Participation by the beta-amino group in brominations not only enhanced reaction rates but also promoted stereo- and regioselectivities. (C) 2000 Elsevier Science Ltd. All rights reserved.
Efficient Cs2CO3-promoted solution and solid phase synthesis of carbonates and carbamates in the presence of TBAI
作者:Ralph N Salvatore、Feixia Chu、Advait S Nagle、Elona A Kapxhiu、Richard M Cross、Kyung Woon Jung
DOI:10.1016/s0040-4020(02)00286-7
日期:2002.4
Novel solution and solid-phase methods for the synthesis of carbonates and carbamates were developed using cesium bases and TBAI via a three-component coupling. Cesium carbonate not only promoted successful carbonylations of alcohols and carbamations of amines, but also suppressed common side reactions traditionally seen using existing protocols. Various alcohols and amines were examined, using a wide
Efficient Carbamate Synthesis via a Three-Component Coupling of an Amine, CO<sub>2</sub>, and Alkyl Halides in the Presence of Cs<sub>2</sub>CO<sub>3</sub> and Tetrabutylammonium Iodide
作者:Ralph N. Salvatore、Seung Il Shin、Advait S. Nagle、Kyung Woon Jung