2437-25-4Relevant articles and documents
Fatty acid methyl esters into nitriles: Acid-base properties for enhanced catalysts
Mekki-Berrada,Bennici,Gillet,Couturier,Dubois,Auroux
, p. 30 - 37 (2013)
Fatty nitriles have lately become of interest in the frame of biofuels or for the valorization of the oil part of biomass as fine chemicals such as polymers. The production of long-chain fatty nitriles by direct reaction of esters with ammonia has however not been academically extensively studied, although several catalysts were developed and published in patents. Acid-base features are implicitly considered as leading the catalysis of this reaction, but no direct correlation was investigated with any nature or number of acidic or basic sites. The present study aims at understanding which sites are responsible of this reaction and thus how to design better catalysts. Strong acidity correlates at 300 C for ester conversion and nitrile yield, suggesting a common nature of the reaction among all kinds of catalysts. An upper strength limit, over which undesirable side-products appear, was evaluated, and the factors influencing the production of N-methyl amide were analyzed.
Facile dehydration of primary amides to nitriles catalyzed by lead salts: The anionic ligand matters
Ruan, Shixiang,Ruan, Jiancheng,Chen, Xinzhi,Zhou, Shaodong
, (2020/12/09)
The synthesis of nitrile under mild conditions was achieved via dehydration of primary amide using lead salts as catalyst. The reaction processes were intensified by not only adding surfactant but also continuously removing the only by-product, water from the system. Both aliphatic and aromatic nitriles can be prepared in this manner with moderate to excellent yields. The reaction mechanisms were obtained with high-level quantum chemical calculations, and the crucial role the anionic ligand plays in the transformations were revealed.
A Molecular Iron-Based System for Divergent Bond Activation: Controlling the Reactivity of Aldehydes
Chatterjee, Basujit,Jena, Soumyashree,Chugh, Vishal,Weyhermüller, Thomas,Werlé, Christophe
, p. 7176 - 7185 (2021/06/30)
The direct synthesis of amides and nitriles from readily available aldehyde precursors provides access to functional groups of major synthetic utility. To date, most reliable catalytic methods have typically been optimized to supply one product exclusively. Herein, we describe an approach centered on an operationally simple iron-based system that, depending on the reaction conditions, selectively addresses either the C=O or C-H bond of aldehydes. This way, two divergent reaction pathways can be opened to furnish both products in high yields and selectivities under mild reaction conditions. The catalyst system takes advantage of iron's dual reactivity capable of acting as (1) a Lewis acid and (2) a nitrene transfer platform to govern the aldehyde building block. The present transformation offers a rare control over the selectivity on the basis of the iron system's ionic nature. This approach expands the repertoire of protocols for amide and nitrile synthesis and shows that fine adjustments of the catalyst system's molecular environment can supply control over bond activation processes, thus providing easy access to various products from primary building blocks.
Method for continuous preparation of nitriles by amides (by machine translation)
-
Paragraph 0033-0054; 0061-0066, (2020/12/15)
The method comprises the following steps: preparing a lead salt supported by a molecular sieve by a lead salt and a molecular sieve through an impregnation method; and filling a molecular sieve-loaded lead catalyst into a fixed bed reactor. The amide or amide solution is sent into a fixed bed reactor from the top of the fixed bed to be subjected to catalytic dehydration, and the obtained reaction product is led out from the bottom of the fixed bed. The reaction product is separated to obtain the crude product of the nitrile corresponding to the amide. A fixed bed continuous production process is adopted, the reaction process is simple, the production efficiency is high, the product post-treatment is simple, and industrial production is easy to realize. (by machine translation)
