4476-12-4Relevant academic research and scientific papers
Direct Amidation of Esters by Ball Milling**
Barreteau, Fabien,Battilocchio, Claudio,Browne, Duncan L.,Godineau, Edouard,Leitch, Jamie A.,Nicholson, William I.,Payne, Riley,Priestley, Ian
supporting information, p. 21868 - 21874 (2021/09/02)
The direct mechanochemical amidation of esters by ball milling is described. The operationally simple procedure requires an ester, an amine, and substoichiometric KOtBu and was used to prepare a large and diverse library of 78 amide structures with modest to excellent efficiency. Heteroaromatic and heterocyclic components are specifically shown to be amenable to this mechanochemical protocol. This direct synthesis platform has been applied to the synthesis of active pharmaceutical ingredients (APIs) and agrochemicals as well as the gram-scale synthesis of an active pharmaceutical, all in the absence of a reaction solvent.
Metal-free transamidation of benzoylpyrrolidin-2-one and amines under aqueous conditions
Joseph, Devaneyan,Lee, Sunwoo,Park, Myeong Seong
supporting information, p. 6227 - 6232 (2021/07/28)
N-Acyl lactam amides, such as benzoylpyrrolidin-2-one, benzoylpiperidin-2-one, and benzoylazepan-2-one reacted with amines in the presence of DTBP and TBAI to afford the transamidated products in good yields. The reactions were conducted under aqueous conditions and good functional group tolerance was achieved. Both aliphatic and aromatic primary amines displayed good activity under metal-free conditions. A radical reaction pathway is proposed.
Enantiospecific Synthesis of Nepetalactones by One-Step Oxidative NHC Catalysis
Harnying, Wacharee,Neud?rfl, J?rg-M.,Berkessel, Albrecht
supporting information, p. 386 - 390 (2020/02/04)
An efficient oxidative NHC-catalyzed one-step transformation of (S)-or (R)-8-oxocitronellal to nepetalactone (NL) in enantio- A nd diastereomerically pure form has been developed. Several new and "easy to make" N-Mes-or N-Dipp-substituted 1,2,4-triazolium salts carrying nitroaromatic groups on N1 were synthesized and evaluated as precatalysts in combination with base and stoichiometric organic oxidant. Under optimized conditions, NLs are accessible in very good yields and diastereomerically pure under mild conditions. The oxidant used could be recovered and recycled under operationally simple conditions.
Nickel/briphos-catalyzed transamidation of unactivated tertiary amides
Kim, Hyunwoo,Lee, Sunwoo,Shin, Taeil,Yang, Dahyeon
supporting information, p. 6053 - 6057 (2020/10/27)
The transamidation of tertiary amides was achieved via nickel catalysis in combination with briphos ligands. N-Methyl-N-phenylbenzamide derivatives reacted with primary amines in the presence of NiCl2/briphos L4 to provide the transamidated products in moderate to good yields. Primary aromatic amines delivered higher product yields than aliphatic amines.
Overcoming solid handling issues in continuous flow substitution reactions through ionic liquid formation
Kashani, Saeed,Sullivan, Ryan J.,Andersen, Mads,Newman, Stephen G.
supporting information, p. 1748 - 1753 (2018/04/30)
Substitutions such as acylations, arylations, and alkylations are some of the most commonly run reactions for building complex molecules. However, the requirement of a stoichiometric base to scavange acid by-products creates significant challenges when operating in continuous flow due to solid handling issues associated with precipitating base·HX salts. We present a general and simple strategy to overcome these solid handling issues through the use of acid scavenging organic bases that generate low- to moderate-melting ionic liquids upon protonation. The application of these bases towards the most commonly run substitutions are demonstrated, enabling reactions to be run in flow without requiring additional equipment, specific solvents, or dilute reaction conditions to prevent clogging.
Multinuclear Cu(I) Clusters Featuring a New Triply Bridging Coordination Mode of Phosphaamidinate Ligands
Rathnayaka, Suresh C.,Lindeman, Sergey V.,Mankad, Neal P.
, p. 9439 - 9445 (2018/08/17)
Phosphabenzamidine [mes-NH-C(Ph)=P-mes) (1) and phosphaformamidine (mes-NH-CH=P-mes) (4) ligands have been synthesized and characterized. The conjugate bases of 1 and 4 coordinate by each bridging three Cu(I) ions, forming hexa- and tetranuclear clusters Cu6[mes-N=C(Ph)-P-mes]3Cl4Li(THF)2 (3) and Cu4[mes-N=CH-P-mes]4 (5), respectively. Both clusters have been fully characterized using 1H NMR, 31P NMR, and X-ray crystallography. Complexes 3 and 5 exhibit a previously unknown coordination mode of phosphaamidinates, which are far less studied than their well-known amidinate counterparts.
Synthesis of N -Aryl Amides by Ligand-Free Copper-Catalyzed ipso -Amidation of Arylboronic Acids with Nitriles
Qiao, Yan,Li, Gaoqiang,Liu, Sha,Yangkai, Yujie,Tu, Jingxuan,Xu, Feng
supporting information, p. 1834 - 1838 (2017/04/06)
A facile copper-catalyzed ipso-amidation of arylboronic acids with nitriles has been developed. The method provides a highly efficient and economical synthesis of N-aryl amides with a broad substrate scope.
Sulfur–Fluoride Exchange (SuFEx)-Mediated Synthesis of Sterically Hindered and Electron-Deficient Secondary and Tertiary Amides via Acyl Fluoride Intermediates
Smedley, Christopher J.,Barrow, Andrew S.,Spiteri, Christian,Giel, Marie-Claire,Sharma, Pallavi,Moses, John E.
, p. 9990 - 9995 (2017/08/01)
Amide bond formation is one of the most executed reactions in chemistry and biology. This is largely due to the ubiquity of the amide functional group in biological molecules, natural products and pharmaceutically important drugs. We report here the development of “SuFExAmide”: a new sulfur–fluoride exchange (SuFEx) click chemistry based protocol for the efficient amidation of carboxylic acids via acyl fluoride intermediates. We have developed benzene-1,3-disulfonyl fluoride as a cost effective, powerful and versatile coupling agent, which delivers challenging secondary and tertiary amides in excellent yields from sterically hindered and electron-deficient amines. The straightforward method offers significant benefits over existing protocols in terms of substrate scope, efficiency and ease of operation and is demonstrated by the synthesis of 44 amides, including GNF6702, an antiprotozoal drug candidate. In the majority of cases, the amide products are obtained in high yield without the need for excess reagents or chromatographic purification.
Vanadium-Catalyzed Oxidative C(CO)-C(CO) Bond Cleavage for C-N Bond Formation: One-Pot Domino Transformation of 1,2-Diketones and Amidines into Imides and Amides
Digwal, Chander Singh,Yadav, Upasana,Ramya, P. V. Sri,Sana, Sravani,Swain, Baijayantimala,Kamal, Ahmed
, p. 7332 - 7345 (2017/07/26)
A novel vanadium-catalyzed one-pot domino reaction of 1,2-diketones with amidines has been identified that enables their transformation into imides and amides. The reaction proceeds by dual acylation of amidines via oxidative C(CO)-C(CO) bond cleavage of 1,2-diketones to afford N,N′-diaroyl-N-arylbenzamidine intermediates. In the reaction, these intermediates are easily hydrolyzed into imides and amides through vanadium catalysis. This method provides a practical, simple, and mild synthetic approach to access a variety of imides as well as amides in high yields. Moreover, one-step construction of imide and amide bonds with a long-chain alkyl group is an attractive feature of this protocol.
RhIII-Catalyzed C-H Allylation of Amides and Domino Cycling Synthesis of 3,4-Dihydroisoquinolin-1(2H)-ones with N-Bromosuccinimide
Dai, Huimin,Yu, Chao,Lu, Changsheng,Yan, Hong
supporting information, p. 1255 - 1259 (2016/03/16)
A RhIII-catalyzed C-H allylation of electron-deficient arenes, heteroarenes, and alkenes at room temperature was developed with allyl bromide. The reaction was carried out in diethyl ether without dehydration, and C-H activation was assisted by the directing anionic nitrogen of the aniline-derived amide. Following the allylation, a domino cycling synthesis of 3,4-dihydroisoquinolin-1(2H)-ones with N-bromosuccinimide (NBS) through intramolecular aminobromination of the introduced double bond was achieved. A C-H allylation of amides with allyl halides at room temperature and a tandem synthesis of 3,4-dihydroisoquinolin-1(2H)-ones with N-bromosuccinimide (NBS) are reported.
