Broadly Applicable Ytterbium-Catalyzed Esterification, Hydrolysis, and Amidation of Imides
作者:Céline Guissart、Andre Barros、Luis Rosa Barata、Gwilherm Evano
DOI:10.1021/acs.orglett.8b01896
日期:2018.9.7
An efficient, broadlyapplicable, operationally simple, and divergent process for the transformation of imides into a range of carboxylic acid derivatives under mild conditions is reported. By simply using catalytic amounts of ytterbium(III) triflate as a Lewis acid promoter in the presence of alcohols, water, amines, or N,O-dimethylhydroxylamine, a broad range of imides is smoothly and readily converted
Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
作者:P. Veeraraghavan Ramachandran、Henry J. Hamann、Shivani Choudhary
DOI:10.1021/acs.orglett.0c03184
日期:2020.11.6
Amine-boranes serve as dual-purpose reagents for direct amidation, activating aliphatic and aromatic carboxylicacids and, subsequently, delivering amines to provide the corresponding amides in up to 99% yields. Delivery of gaseous or low-boiling amines as their borane complexes provides a major advantage over existing methodologies. Utilizing amine-boranes containing borane incompatible functionalities
The versatile conversion of propargylic amides to the respective 2-substituted 5-methyloxazoles was efficiently catalyzed by Zn(OTf)2 (5 mol%) under microwave irradiation in toluene. The method was applicable to a wide range of aliphatic, aromatic and heteroaromatic propargylic amides and thus represents a useful method which is complementary to the existing metal-catalyzed protocols, considering the
decarboxylative amidation of α-ketoacids by using inexpensive tert-butyl hydroperoxide (TBHP), which is characterized by high yields, a broad substrate scope, mild reaction conditions, and a unique chemoselectivity. These features enable the synthesis of peptides from amino acid derived α-ketoacids under preservation of the stereochemical information.
d ligands (MTDL) design. New propargylamine substituted derivatives combined with salicylic and cinnamic scaffolds were designed and synthesized as potentialcholinesterases and monoamine oxidases (MAOs) inhibitors. They were evaluated in vitro for inhibition of acetyl- (AChE) and butyrylcholinesterase (BuChE) using Ellman’s method. All the compounds act as dual inhibitors. Most of the derivatives