Cs2CO3 in pyrrolidinone promoted hydration of functionalized (hetero)aryl nitriles under metal-free conditions

Magnetic N-doped CNT stabilized Cu2O as a catalyst for N-arylation of nitriles and aryl halides in a biocompatible deep eutectic solvent

This study documented the hydrolysis of nitriles by copper(i) oxide immobilized on nitrogen-doped carbon nanotubes (N-CNT/Fe3O4-Cu2O) to yield corresponding amides in the presence of a deep eutectic solvent (ChOH/Gly). Furthermore, the aforementioned catalyst can facilitate the coupling reaction between aryl halides and amides derived by nitrile hydrolysis. Consequently, the integration of two copper-catalyzed processes can efficiently provide N-aryl amides. Choline hydroxide in a deep eutectic solvent serves as a cost-effective organic catalyst in nitrie hydrolysis by forming hydrogen bonds with nitrile, thereby activating it. The catalyst generated higher to satisfactory product yields. One of the special benefits of the catalyst is that it can be restored through the addition of an external magnetic field.

Transition metal-free NaOH-catalyzed hydration of nitriles to primary amides in NH3·H2O-DMSO mixture

In this paper, we reported an efficient protocol for hydration of aryl(hetero) and alkyl nitriles toward primary amides with 0.1 equiv. NaOH in NH₃·H₂O-DMSO under mild conditions. Various substituted nitriles are smoothly converted to the corresponding amides with good to excellent isolated yields. Gram-scale reactions were also performed to produce the desired products in high yields. In addition, the excessive hydrolysis of the nitrile to form the corresponding carboxylic acid was also achieved with increasing the amount of NaOH and prolonging the reaction time.

Copper-catalyzed tandem oxidative synthesis of quinazolinones from 2-aminobenzonitriles and benzyl alcohols

A highly efficient, one-pot Cu(OAc)₂/Cs₂CO₃-catalyzed protocol for the aerobic oxidative synthesis of quinazolinones from readily available benzyl alcohols and 2-aminobenzonitriles with molecular oxygen as the terminal oxidant has been successfully developed.

"On-Water" Synthesis of Quinazolinones and Dihydroquinazolinones Starting from o-Bromobenzonitrile

A versatile and practical “on-water” protocol was newly developed to synthesize quinazolinones using o-bromobenzonitrile as a novel starting material. Studies have found that air as well as water plays an important role in synthesis of quinazolinones. Further investigation indicated that dihydroquinazolinones can be prepared with this protocol under the protection of N₂. The protocol can be extended to other substrates and various quinazolinones and dihydroquinazolinones were obtained. o-Bromobenzamide, o-aminobenzonitrile, and o-aminobenzamide were also evaluated as starting materials, and the results further proved the versatility of this protocol, especially towards dihydroquinazolinones.

Sodium Azide as a Catalyst for the Hydration of Nitriles to Primary Amides in Water

The selective conversion of aromatic nitriles to primary amides has been accomplished using sodium azide. The corresponding amides were obtained efficiently in excellent yields. This reaction was carried out under eco-friendly conditions using water in the absence of organic solvents.

Transition-metal-free hydration of nitriles using potassium tert-butoxide under anhydrous conditions

Potassium tert-butoxide acts as a nucleophilic oxygen source during the hydration of nitriles to give the corresponding amides under anhydrous conditions. The reaction proceeds smoothly for a broad range of substrates under mild conditions, providing an efficient and economically affordable synthetic route to the amides in excellent yields. This protocol does not need any transition-metal catalyst or any special experimental setup and is easily scalable to bulk scale synthesis. A single-electron-transfer radical mechanism as well as an ionic mechanism have been proposed for the hydration process.

Selective NaOH-catalysed hydration of aromatic nitriles to amides

The selective synthesis of aromatic and heteroaromatic amides through base-catalysed hydration of nitriles was achieved using inexpensive and commercially available NaOH as the only catalyst.