Organobase-Catalyzed Amidation of Esters with Amino Alcohols

Abstract

A base-mediated procedure for the amidation of unactivated esters with amino alcohols is reported. Optimization and exemplification of the catalytic process are described, furnishing products in 40-100% isolated yield.

Regioselective Functionalization of 3‐Hydroxy‐pyridine Carboxylates by Neighboring Group Assistance

“…The use of stoichiometric amounts of activating reagents in stepwise manipulations generally compromises transformation economy . Therefore, transition‐metal‐mediated or catalyzed transesterification and ester–amide exchange reactions in a homogeneous medium have attracted considerable interest ,. However, regioselective transformations of esters are typically limited to the enzymatic hydrolysis of symmetrical methyl esters…”

Synthesis of β-hydroxyacetamides from unactivated ethyl acetates under base-free conditions and microwave irradiation

“…Thin layer chromatography was carried out on pre-coated TLC sheets of silica gel 60 F254 (E. Merck). NMR spectra were recorded on Varian System instrument (400 MHz for 1 H and 100 MHz for 13 C. The spectra were obtained in CDCl 3 , CD 3 OD, and DMSO-d 6 …”

“…1 Amides bearing chiral 1,2-amino alcohols, which have been used as building blocks in the synthesis of more complex molecules, 2 and as chiral ligands, 3 are usually prepared by the reaction of activated carboxylic acids with chiral 1,2-amino alcohols. Other amides bearing chiral amino alcohols have been obtained by reactions between mildly activated esters and 1,2-amino alcohols without the need of coupling reagents, 4 or in a single-step carbene-catalyzed reaction of esters with chiral 1,2-amino alcohols, 5 catalyzed by 2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine (BEMP), 6 and using K 3 PO 4 as the catalyst. 7 However, these methods suffer from one or more disadvantages such as the use of specialized handling techniques and tedious work-up, long reaction times, vigorous reaction conditions, the requirement of an excess of reagents, the use of solvent, which leads to unsatisfactory yields, and a lack of generality.…”

Chiral separation of aliphatic primary amino alcohols as o‐phthaldialdehyde/mercaptoethanol derivatives on polysaccharide‐based chiral stationary phases

“…2 Hence, their enantiomeric separation is of great significance during the drug development process and during quality control of raw materials and intermediates as well. 2 Hence, their enantiomeric separation is of great significance during the drug development process and during quality control of raw materials and intermediates as well.…”