n of alkenes with anilines has been developed for the atom-economical synthesis of 2-substituted propanamides bearing an α-stereocenter. A novel phosphoramidite ligand L16 was discovered which exhibited very high reactivity and selectivity in the reaction. This asymmetric Markovnikov hydroaminocarbonylation employs readily available starting materials and tolerates a wide range of functional groups
TCFH–NMI: Direct Access to <i>N</i>-Acyl Imidazoliums for Challenging Amide Bond Formations
作者:Gregory L. Beutner、Ian S. Young、Merrill L. Davies、Matthew R. Hickey、Hyunsoo Park、Jason M. Stevens、Qingmei Ye
DOI:10.1021/acs.orglett.8b01591
日期:2018.7.20
Challenging couplings of hindered carboxylic acids with non-nucleophilic amines to form amide bonds can be accomplished in high yields, and in many cases, with complete retention of the adjacent stereogenic centers using the combination of N,N,N′,N′-tetramethylchloroformamidinium hexafluorophosphate (TCFH) and N-methylimidazole (NMI). This method allows for in situ generation of highly reactive acyl imidazolium
Synthesis of Dipeptide, Amide, and Ester without Racemization by Oxalyl Chloride and Catalytic Triphenylphosphine Oxide
作者:Ji-Wei Ren、Meng-Nan Tong、Yu-Fen Zhao、Feng Ni
DOI:10.1021/acs.orglett.1c02614
日期:2021.10.1
An efficient triphenylphosphine oxide-catalyzed amidation and esterification for the rapid synthesis of a series of dipeptides, amides, and esters is described. This reaction is applicable to challenging couplings of hindered carboxylic acids with weakly nucleophilic amines or alcohols, giving the products in good yields (67–90%) without racemization. This system employs the highly reactive intermediate