Direct Synthesis of Nitriles from Carboxylic Acids Using Indium-Catalyzed Transnitrilation: Mechanistic and Kinetic Study

Abstract

Aliphatic and aromatic carboxylic acids can be quantitatively converted to the corresponding nitriles in the presence of catalysts using acetonitrile both as a solvent and reactant at 200 °C. This transformation is based on the acid–nitrile exchange (i.e., transnitrilation) and uses a nontoxic and water resistant catalyst, indium trichloride (InCl3). The mechanism of the transnitrilation was investigated both experimentally and computationally and compared to the previously proposed mechanism. In contrast to the usually assumed formation of amide as an intermediate, transnitrilation is an equilibrium reaction and proceeds via an equilibrated Mumm reaction with the formation of an imide as an intermediate. A simple and reversible mechanism was proposed for this reaction, which was validated by kinetics measurement and by density functional theory calculations of the reaction intermediates and reaction mechanisms.

A copper-catalyzed four-component reaction of arylcyclopropanes, nitriles, carboxylic acids and N-fluorobenzenesulfonimide: facile synthesis of imide derivatives

“…Based on the above experimental results and previously reported researche studies, 5 a – c ,15,18,19 a plausible mechanism is depicted in Scheme 3. A single electron oxidation between arylcyclopropane 1 and the Cu( iii )–N species A or the radical species C occurred to form the radical cation E and the nitrogen anion D , followed by nucleophilic ring-opening and oxidization to generate the benzylic carbocation intermediate G .…”

Programing a cyanide-free transformation of aldehydes to nitriles and one-pot synthesis of amides through tandem chemo-enzymatic cascades

“…Therefore, the cyanide-free synthesis of nitrile has attracted great attention from chemical scientists. 9 A variety of strategies have been recently developed using less toxic cyanide sources from different substrates in the last decade, including alkenes, 10,11 amines, 12,13 carboxylic acids, 14,15 primary alcohols, 16,17 and aldehydes. [18][19][20] However, most of them depended on transition metals (e.g., Cu, Fe, Ru, Pd, etc.)…”

Synthesis of densely substituted pyridine derivatives from nitriles by a non-classical [4+2] cycloaddition/1,5-hydrogen shift strategy

“…As illustrated in Fig. 2B, in the nucleophilic addition of nitriles, the most reported reaction partners have been focused on the highly reactive nitrogen, [44][45][46][47][48][49][50][51][52] oxygen, [53][54][55][56][57][58][59][60][61] and sulfur nucleophiles till now. [62][63][64] For carbon pronucleophiles, the related studies are only limited to sp, sp 2 , and sp 3 with α-electron withdrawing group (i.e.…”