4695-13-0Relevant academic research and scientific papers
Reactivity of molybdenum-nitride complex bearing pyridine-based PNP-type pincer ligand toward carbon-centered electrophiles
Arashiba, Kazuya,Itabashi, Takayuki,Kuriyama, Shogo,Nishibayashi, Yoshiaki
, p. 1946 - 1954 (2022/02/11)
A molybdenum-nitride complex bearing a pyridine-based PNP-type pincer ligand derived from dinitrogen is reacted with various kinds of carbon-centered electrophiles to functionalize the nitride ligand in the molybdenum complex. Methylation with MeOTf and acylation with diphenylacetyl chloride of the nitride complex afford the corresponding imide complexes via a carbon-nitrogen bond formation. In the case of reactions with phenylisocyanate and diphenylketene, the PNP ligand works as a non-innocent ligand to form the corresponding ureate and acylimide complexes, respectively. These newly synthesized complexes are characterized by X-ray analysis. As a further transformation of the prepared imide complexes, hydrolysis of the molybdenum-acylimide complex proceeds to give the corresponding amide as an organonitrogen compound together with the corresponding molybdenum-oxo complex. This result indicates that the nitrogen molecule is converted into organic amide mediated by the molybdenum-nitride complex.
Bis-Rhodamines Bridged with a Diazoketone Linker: Synthesis, Structure, and Photolysis
Belov, Vladimir N.,Bossi, Mariano L.,Hell, Stefan W.,Shojaei, Heydar
, p. 56 - 65 (2022/01/03)
Two fluorophores bound with a short photoreactive bridge are fascinating structures and remained unexplored. To investigate the synthesis and photolysis of such dyes, we linked two rhodamine dyes via a diazoketone bridge (?COCN2?) attached to p
Hydration of Aliphatic Nitriles Catalyzed by an Osmium Polyhydride: Evidence for an Alternative Mechanism
Babón, Juan C.,Esteruelas, Miguel A.,López, Ana M.,O?ate, Enrique
, p. 7284 - 7296 (2021/05/29)
The hexahydride OsH6(PiPr3)2 competently catalyzes the hydration of aliphatic nitriles to amides. The main metal species under the catalytic conditions are the trihydride osmium(IV) amidate derivatives OsH3{κ2-N,O-[HNC(O)R]}(PiPr3)2, which have been isolated and fully characterized for R = iPr and tBu. The rate of hydration is proportional to the concentrations of the catalyst precursor, nitrile, and water. When these experimental findings and density functional theory calculations are combined, the mechanism of catalysis has been established. Complexes OsH3{κ2-N,O-[HNC(O)R]}(PiPr3)2 dissociate the carbonyl group of the chelate to afford κ1-N-amidate derivatives, which coordinate the nitrile. The subsequent attack of an external water molecule to both the C(sp) atom of the nitrile and the N atom of the amidate affords the amide and regenerates the κ1-N-amidate catalysts. The attack is concerted and takes place through a cyclic six-membered transition state, which involves Cnitrile···O-H···Namidate interactions. Before the attack, the free carbonyl group of the κ1-N-amidate ligand fixes the water molecule in the vicinity of the C(sp) atom of the nitrile.
Direct synthesis of amides from nonactivated carboxylic acids using urea as nitrogen source and Mg(NO3)2or imidazole as catalysts
Blacker, A. John,Chhatwal, A. Rosie,Lomax, Helen V.,Marcé, Patricia,Williams, Jonathan M. J.
, p. 5808 - 5818 (2020/06/21)
A new method for the direct synthesis of primary and secondary amides from carboxylic acids is described using Mg(NO3)2·6H2O or imidazole as a low-cost and readily available catalyst, and urea as a stable, and easy to manipulate nitrogen source. This methodology is particularly useful for the direct synthesis of primary and methyl amides avoiding the use of ammonia and methylamine gas which can be tedious to manipulate. Furthermore, the transformation does not require the employment of coupling or activating agents which are commonly required.
One-pot method for the synthesis of 1-aryl-2-aminoalkanol derivatives from the corresponding amides or nitriles
Bobal, Pavel,Otevrel, Jan,Svestka, David
, p. 25029 - 25045 (2020/07/14)
We have identified a novel one-pot method for the synthesis of β-amino alcohols, which is based on C-H bond hydroxylation at the benzylic α-carbon atom with a subsequent nitrile or amide functional group reduction. This cascade process uses molecular oxygen as an oxidant and sodium bis(2-methoxyethoxy)aluminum hydride as a reductant. The substrate scope was examined on 30 entries and, although the respective products were provided in moderate yields only, the above simple protocol may serve as a direct and powerful entry to the sterically congested 1,2-amino alcohols that are difficult to prepare by other routes. The plausible mechanistic rationale for the observed results is given and the reaction was applied to a synthesis of a potentially bioactive target. This journal is
Catalytic C-C coupling of diazo compounds with arylboronic acids: Using surface modified sewage sludge as catalyst
Huang, Fei,Huang, He,Hughes, Timothy,Xie, Yuxing,Xu, Jun,Yu, Yang,Zhang, Zhipeng
, p. 4165 - 4173 (2020/07/14)
A green, mild and efficient synthesis of diarylmethines using sewage sludge-derived carbonaceous materials (SW) by perchloric acid catalyzed coupling reactions between diazo compounds and arylboronic acids was developed. The reaction shows a high level of functional tolerance and a broad substrate scope. Furthermore, the highly selective 1,2-alkyl shift products were furnished through the sterically demanding R4, R5 migration of diazo compounds (3-diazochromanone). The structures of 1,2-shift products have been further confirmed by single-crystal X-ray analysis. Significantly, the synthesis of the core structures of darifenacin (a clinical drug for overactive bladder syndrome, OAB) and diclofensine (a stimulant drug showing antidepressant and monoamine reuptake inhibitor activity) further demonstrated the efficacy and synthetic potential of this method. This journal is
A continuous-flow synthesis of primary amides from hydrolysis of nitriles using hydrogen peroxide as oxidant
Zhan, Wei,Ji, Ling,Ge, Ze-mei,Wang, Xin,Li, Run-tao
, p. 1527 - 1532 (2018/02/21)
A continuous-flow synthesis of primary amides from hydrolysis of nitriles using hydrogen peroxide as oxidant has been developed. Using this procedure, a variety of nitriles could be smoothly transformed into the desired primary amides in good to excellent yields. The mild reaction conditions and the flowing reaction system greatly improved the safety and make the reaction easy to scale up.
Development and Utilization of a Palladium-Catalyzed Dehydration of Primary Amides to Form Nitriles
Al-Huniti, Mohammed H.,Rivera-Chávez, José,Colón, Katsuya L.,Stanley, Jarrod L.,Burdette, Joanna E.,Pearce, Cedric J.,Oberlies, Nicholas H.,Croatt, Mitchell P.
supporting information, p. 6046 - 6050 (2018/09/27)
A palladium(II) catalyst, in the presence of Selectfluor, enables the efficient and chemoselective transformation of primary amides into nitriles. The amides can be attached to aromatic rings, heteroaromatic rings, or aliphatic side chains, and the reactions tolerate steric bulk and electronic modification. Dehydration of a peptaibol containing three glutamine groups afforded structure-activity relationships for each glutamine residue. Thus, this dehydration can act similarly to an alanine scan for glutamines via synthetic mutation.
Hemilability-Driven Water Activation: A NiII Catalyst for Base-Free Hydration of Nitriles to Amides
Singh, Kuldeep,Sarbajna, Abir,Dutta, Indranil,Pandey, Pragati,Bera, Jitendra K.
, p. 7761 - 7771 (2017/06/06)
The NiII complex 1 containing pyridyl- and hydroxy-functionalized N-heterocyclic carbenes (NHCs) is synthesized and its catalytic utility for the selective nitrile hydration to the corresponding amide under base-free conditions is evaluated. The title compound exploits a hemilabile pyridyl unit to interact with a catalytically relevant water molecule through hydrogen-bonding and promotes a nucleophilic water attack to the nitrile. A wide variety of nitriles is hydrated to the corresponding amides including the pharmaceutical drugs rufinamide, Rifater, and piracetam. Synthetically challenging α-hydroxyamides are accessed from cyanohydrins under neutral conditions. Related catalysts that lack the pyridyl unit (i.e., compounds 2 and 4) are not active whereas those containing both the pyridyl and the hydroxy or only the pyridyl pendant (i.e., compounds 1 and 3) show substantial activity. The linkage isomer 1′ where the hydroxy group is bound to the metal instead of the pyridyl group was isolated under different crystallization conditions insinuating a ligand hemilabile behavior. Additional pKa measurements reveal an accessible pyridyl unit under the catalytic conditions. Kinetic studies support a ligand-promoted nucleophilic water addition to a metal-bound nitrile group. This work reports a Ni-based catalyst that exhibits functional hemilability for hydration chemistry.
Chemoselective hydration of nitriles to amides using hydrated ionic liquid (IL) tetrabutylammonium hydroxide (TBAH) as a green catalyst
Veisi, Hojat,Maleki, Behrooz,Hamelian, Mona,Ashrafi, Samaneh Sedigh
, p. 6365 - 6371 (2015/02/19)
A transition metal-free process, catalyzed by tetrabutylammonium hydroxide (TBAH), has been developed for the convenient and selective hydration of nitriles to the corresponding amides. The present process converts aromatic, aliphatic, and heteroaromatic nitriles with a wide variety of functional groups into amides. The regioselective hydration of one nitrile moiety in the presence of another nitrile group gives the present protocol high impact.
