Efficient preparation of chiral diamines via Red-Al reduction of N-Boc-protected amino acid-derived secondary amides
作者:Eric A. Voight、Matthew S. Bodenstein、Norihiro Ikemoto、Michael H. Kress
DOI:10.1016/j.tetlet.2006.01.056
日期:2006.3
reduction of N-Boc-protected amino acid-derived secondary amides, avoiding the formation of overreduction and cyclic urea byproducts. The method is showcased by the efficient formal synthesis of NK-1antagonistLY303870.
Direct Amidation of Amino Acid Derivatives Catalyzed by Arylboronic Acids: Applications in Dipeptide Synthesis
作者:Shouxin Liu、Yihua Yang、Xinwei Liu、Farhana K. Ferdousi、Andrei S. Batsanov、Andrew Whiting
DOI:10.1002/ejoc.201300560
日期:2013.9
The direct amidation of aminoacidderivatives catalyzed by arylboronic acids has been examined. The reaction was generally slow relative to simple amine-carboxylic acid combinations though proceeded at 65–68 °C generally avoiding racemization. 3,4,5-Trifluorophenylboronic and o-nitrophenylboronic acids were found to be the best catalysts, though for slower dipeptide formations, high catalyst loadings
Preparation of polymer-bound pyrazolone active esters for combinatorial chemistry
作者:Jang-Woong Byun、Dong-Hoon Lee、Yoon-Sik Lee
DOI:10.1016/j.tetlet.2003.09.044
日期:2003.10
The preparation of solid-phase active esters from a new pyrazolone linker resin is described. N-Acylation using this resin provides various amide products with a high conversion rate and good purity under mild conditions. The polymer-bound pyrazolone linkers are stable in the reaction conditions and are resistant to hydrolysis. Moreover, this resin can also be reused repeatedly without a loss of reactivity. (C) 2003 Published by Elsevier Ltd.