Pd(ii)-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates under mild conditions

Abstract

A novel Pd-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates has been realized under mild reaction conditions. This method provides an efficient access to N-mono- or N,N-disubstituted benzamides and benzoates.

Palladium-catalyzed C–H bond carboxylation of acetanilides: an efficient usage of N,N-dimethyloxamic acid as the carboxylate source

“…The development of other efficient carboxylate agents has not been reported yet. In continuation of our previous studies, [13][14][15] we report herein that N,N-dimethyloxamic acid, an easily obtained reagent, 16,17 could act as an efficient carboxylate agent in the palladium-catalyzed coupling of acetanilides for obtaining anthranilic acid derivatives (Scheme 1c).…”

“…Inspired by Ge's work which showed that both the a-oxocarboxylic acids and oxamic acids could be involved in the palladium catalyzed cross coupling reaction through a decarboxylation route, 17,18 we envisioned that N-acyl-2-aminobenbenzamides could be generated via a similar mechanism in the palladium catalyzed cross coupling of acetanilides with oxamic acids. To our surprise, when we used the N,N-dialkyloxamic acid in the palladium catalyzed C-H bond activation of acetanilides, we obtained the N-acyl anthranilic acid as the final product, instead of the decarboxylated product.…”

Palladium-Catalyzed Decarboxylative Cross-Coupling of α-Oxocarboxylic Acids and Their Derivatives

“…27 Encouraged by these results, we developed a novel pathway for the synthesis of aryl amides and esters from potassium aryl trifluoroborates and oxamic acids or oxalate monoesters, respectively. 28 During our investigation, we realized that higher temperatures significantly accelerate the decarboxylation of oxamic acids and oxalate monoesters. The reactions of a wide range of oxamic acids 2 with potassium aryl trifluoroborates 20 were investigated under the optimized conditions (Scheme 10).…”

Transition metal-catalyzed decarboxylative cross-coupling reactions

“…Ge et al reported decarboxylative cross-coupling of trifluoro(organo)borates with 2-ketone acids [66], oxalate monoesters [67], and 2-amino-2-oxoacetates [67] (Scheme 53). This reaction affords aryl ketones, esters, and amides as the products.…”