Nitrile reaction in high‐temperature water: Kinetics and mechanism

Green Medium for the Hydrolysis of 5‐Cyanovaleramide

“…The collision probability between reactant molecules and water molecules increases with increasing reactant concentration for a constant batch reactor volume, resulting in the increase of molar conversion. Traditionally, the accumulation of products resulting from the hydrolysis of nitriles has been known to act as the catalytic species to enhance the reaction rate in high-temperature water [16]. This catalytic effect probably exists in the 5-CVAM hydrolysis system, but it is not obvious; the acceleration of the reaction rate due to the accumulation of products is not as great as the collision probability.…”

“…Depending on the pH, the reaction in aqueous solution may follow different pathways: At high pH the system will follow the so-called "base-catalyzed" route, in which a hydroxyl ion performs a nucleophilic attack on the carbonyl carbon atom next to an amide bond; at low pH, protonation of the carbonyl oxygen atom followed by nucleophilic attack carried out by a water molecule is known as the "acidcatalyzed" pathway [28]. Hydrolysis of nitriles in NCW proceeds basically in terms of the base-catalyzed mechanism because of its lower activation energy [16]. Under basic conditions, it is more difficult to hydrolyze an amide because you need to form a dianion intermediate.…”

“…At present, these organic compounds primarily include amines/imines, amides, nitriles, nitro compounds, esters, ethers, acetals, alkyl halides, anhydrides, and silanes [4]. Nitriles command special attention because of their appearance in industrial waste streams and in the product spectra from the reaction of aliphatic -NO 2 -containing compounds in high-temperature water [16]. Most nitriles are industrially produced as intermediates and building blocks in organic synthesis or as organic solvents.…”

Hydrolysis Kinetics of 2-Pyridinecarboxamide, 3-Pyridinecarboxamide and 4-Pyridinecarboxamide in High-Temperature Water

“…It has acid-or base-catalytic ability, good solubility for organic compounds, and wide tunability of physical properties [1][2][3][4][5][6][7]. In recent years, the research on hydrolysis of nitriles in HTW attracts much attention for potential applications in treatment of industrial waste streams [8] and production of carboxylic acids [9][10][11], since HTW provides a green strategy without strong acid or base catalyst. Amide is the intermediate product of nitrile hydrolysis.…”

Hydrolysis of Adiponitrile in Near‐critical Water

“…Nitriles can hydrolyze in supercritical water or NCW without the addition of any catalysts. [9][10][11] Thus far, many investigations have been concentrated on the hydrolysis reactivity and kinetics of aliphatic and aromatic mononitriles, but few studies have been undertaken on dinitriles. We have successfully realized the hydrolysis of iminodiacetonitrile in NCW without the addition of any catalysts and the preparation of iminodiacetic acid salts assisted with additives.…”