A metal-free approach for the synthesis of amides/esters with pyridinium salts of phenacyl bromides via oxidative C–C bond cleavage

Abstract

An efficient, simple, and metal-free synthetic approach for the N- and O-benzoylation of various amines/benzyl alcohols with pyridinium salts of phenacyl bromides is demonstrated to generate the corresponding amides and esters. This protocol facilitates the oxidative cleavage of a C–C bond followed by formation of a new C–N/C–O bond in the presence of K2CO3. Various pyridinium salts of phenacyl bromides can be readily transformed into a variety of amides and esters which is an alternative method for the conventional amidation and esterification in organic synthesis. High functional group tolerance, broad substrate scope and operational simplicity are the prominent advantages of the current protocol.

Electrochemical Oxidative C–C Bond Cleavage of Ketones for C–N Bond Formation: A Route to Amides

“…The amide functional group is ubiquitous in organic chemistry and is a significant structural module in polymers, natural compounds, and pharmaceuticals. − Therefore, many chemical approaches have been developed to access amide-containing molecules. − Amines have shown a wide spectrum of chemical reactivity among the various nitrogen sources utilized for amide synthesis. For example, the condensation of carboxylic acids or activated carboxylic acid derivatives (acid anhydrides and acid halides) with amines is a powerful method used to construct amide bonds .…”

Tandem oxidative amidation of benzylic alcohols by copper(II) supported on metformin-graphitic carbon nitride nanosheets as an efficient catalyst

“… Entry Alcohol Amine salt Product Yield (%) a Mp. (°C) Found Reported 1 90 105 104–105 52 2 95 111 110–111 53 3 95 120 120–122 54 4 80 163 162–164 55 5 80 140 140–142 56 6 80 97 95–97 49 ...…”

Cobalt catalysed aminocarbonylation of thiols in batch and flow for the preparation of amides

“…1 4-Methoxy-N-(4-methoxybenzyl)benzamide, (7). 22 White solid, 84.5 mg, 26% (method A), 117.1 mg, 36% (method B) and 101.0 mg, 32% (method D). 1 4-Methoxy-N-phenethylbenzamide, (8).…”