53179-04-7Relevant articles and documents
Olefination via Cu-Mediated Dehydroacylation of Unstrained Ketones
Dong, Guangbin,Xu, Yan,Zhou, Xukai
supporting information, p. 20042 - 20048 (2021/12/03)
The dehydroacylation of ketones to olefins is realized under mild conditions, which exhibits a unique reaction pathway involving aromatization-driven C-C cleavage to remove the acyl moiety, followed by Cu-mediated oxidative elimination to form an alkene between the α and β carbons. The newly adopted N′-methylpicolinohydrazonamide (MPHA) reagent is key to enable efficient cleavage of ketone C-C bonds at room temperature. Diverse alkyl- and aryl-substituted olefins, dienes, and special alkenes are generated with broad functional group tolerance. Strategic applications of this method are also demonstrated.
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.
Nitrile Synthesis by Aerobic Oxidation of Primary Amines and in situ Generated Imines from Aldehydes and Ammonium Salt with Grubbs Catalyst
Utsumi, Tatsuki,Noda, Kenta,Kawauchi, Daichi,Ueda, Hirofumi,Tokuyama, Hidetoshi
supporting information, p. 3583 - 3588 (2020/08/05)
Herein, a Grubbs-catalyzed route for the synthesis of nitriles via the aerobic oxidation of primary amines is reported. This reaction accommodates a variety of substrates, including simple primary amines, sterically hindered β,β-disubstituted amines, allylamine, benzylamines, and α-amino esters. Reaction compatibility with various functionalities is also noted, particularly with alkenes, alkynes, halogens, esters, silyl ethers, and free hydroxyl groups. The nitriles were also synthesized via the oxidation of imines generated from aldehydes and NH4OAc in situ. (Figure presented.).
Catalytic Dehydrosulfurization of Thioamides to Nitriles by Gold Nanoparticles Supported on Carbon Nanotubes
Gopi, Elumalai,Geertsen, Valérie,Gravel, Edmond,Doris, Eric
, p. 5758 - 5761 (2019/05/21)
A gold-carbon nanotube nanohybrid was shown to act as an efficient heterogeneous catalyst in the smooth and selective conversion of thioamides to the corresponding nitriles. The reaction was performed under mild conditions (room temperature, atmospheric pressure of oxygen) using only a gold loading of 0.35 mol %. Substituted aromatic or aliphatic nitriles were produced in very good to excellent yields and the catalyst could be easily recycled and reused over several consecutive cycles with no loss in dehydrosulfurization performances.
Triphenylbismuth Dichloride-Mediated Conversion of Thioamides to Nitriles
Gopi, Elumalai,Gravel, Edmond,Doris, Eric
supporting information, p. 4043 - 4045 (2019/06/24)
Thioamides were efficiently converted to nitriles using the pentavalent triphenylbismuth dichloride in combination with triethylamine. The reaction involved the dehydrosulfurization of primary thioamides to afford substituted aromatic or aliphatic nitriles in good to excellent yields. The process was also successfully extended to the synthesis of cyanamides starting from the corresponding thioureas and of thiocyanates from dithiocarbamates.
Direct Synthesis of Free α-Amino Acids by Telescoping Three-Step Process from 1,2-Diols
Inada, Haruki,Shibuya, Masatoshi,Yamamoto, Yoshihiko
supporting information, p. 709 - 713 (2019/01/25)
A practical telescoping three-step process for the syntheses of α-amino acids from the corresponding 1,2-diols has been developed. This process enables the direct synthesis of free α-amino acids without any protection/deprotection step. This method was also effective for the preparation of a 15N-labeled α-amino acid. 1,2-Diols bearing α,β-unsaturated ester moieties afforded bicyclic α-amino acids through intramolecular [3 + 2] cycloadditions. A preliminary study suggests that the resultant α-amino acids are resolvable by aminoacylases with almost complete selectivity.
Metal-Free Oxidation of Primary Amines to Nitriles through Coupled Catalytic Cycles
Lambert, Kyle M.,Bobbitt, James M.,Eldirany, Sherif A.,Kissane, Liam E.,Sheridan, Rose K.,Stempel, Zachary D.,Sternberg, Francis H.,Bailey, William F.
supporting information, p. 5156 - 5159 (2016/04/09)
Synergism among several intertwined catalytic cycles allows for selective, room temperature oxidation of primary amines to the corresponding nitriles in 85-98 % isolated yield. This metal-free, scalable, operationally simple method employs a catalytic quantity of 4-acetamido-TEMPO (ACT; TEMPO=2,2,6,6-tetramethylpiperidine N-oxide) radical and the inexpensive, environmentally benign triple salt oxone as the terminal oxidant under mild conditions. Simple filtration of the reaction mixture through silica gel affords pure nitrile products.
One-Step Synthesis of Nitriles from Acids, Esters and Amides Using DIBAL-H and Ammonium Chloride
Wojtkielewicz, Agnieszka,?otowski, Zenon,Morzycki, Jacek W.
supporting information, p. 2288 - 2292 (2015/09/28)
A convenient, one-step procedure is presented for the conversion of carboxylic acids or their derivatives (esters, lactones, amides) to nitriles with an aminoalane reagent prepared from diisobutylaluminum hydride (DIBAL-H) and ammonium chloride.
PROCESS FOR THE SYNTHESIS OF C11 AND C12 OMEGA-AMINOALKANOIC ACID ESTERS COMPRISING A NITRILATON STEP
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Paragraph 0064-0066, (2014/07/23)
A process for the synthesis of C11 and C12 ω-amino-alkanoic acid esters including a step of continuous nitrilation in the gas phase or in a mixed gas-liquid phase, a step of metathesis and a step of reduction by hydrogenation, using, as raw material, C10 and C11 ω-alkenoic acid esters.
A mild synthesis of nitriles by von Braun degradation of amides using triphenyl phosphite-halogen-based reagents
Vaccari, Daniele,Davoli, Paolo,Spaggiari, Alberto,Prati, Fabio
experimental part, p. 1317 - 1320 (2009/04/06)
A mild procedure for the synthesis of aromatic and aliphatic nitriles is disclosed. In the presence of bromotriphenoxyphosphonium bromide (TPPBr 2), N-alkyl and N,N-dialkyl amides undergo von Braun degradation to nitriles in good to excellent yields under the mildest conditions ever reported. The reaction proceeds via formation of an iminoyl bromide intermediate at -60°C, which subsequently dealkylate upon refluxing in chloroform or even at room temperature. In the case of N-tert-butyl, N-α-phenylethyl and N-benzhydryl amides, chlorotriphenoxyphosphonium chloride (TPPCl2) generated at -30°C was also effective. Georg Thieme Verlag Stuttgart.
