776-75-0Relevant academic research and scientific papers
A practical modification of the Barton-McCombie reaction and radical O- to S- rearrangement of xanthates
Quiclet-Sire, Beatrice,Zard, Samir Z.
, p. 9435 - 9438 (1998)
The C-O bond in xanthates derived from carbohydrates can be reductively cleaved by heating in 2-propanol in the presence of equimolar amounts of dilauroyl peroxide, added in small portions; if benzene is used as the solvent, an O- to S- rearrangement of the xanthate occurs.
Microwave assisted, palladium catalyzed aminocarbonylations of heteroaromatic bromides using solid Mo(CO)6 as the carbon monoxide source
Letavic, Michael A.,Ly, Kiev S.
, p. 2339 - 2343 (2007)
The direct conversion of a variety of heteroaromatic bromides into heteroaromatic amides is described. This reaction utilizes Mo(CO)6 as the carbon monoxide source and is performed using microwave heating allowing for very short reaction times. This convenient methodology allows for the preparation of a variety of heteroaromatic amides useful in medicinal chemistry applications.
TBAI-catalyzed C–N bond formation through oxidative coupling of benzyl bromides with amines: a new avenue to the synthesis of amides
Kumar, Dhirendra,Maury, Suresh Kumar,Kumari, Savita,Kamal, Arsala,Singh, Himanshu Kumar,Singh, Sundaram,Srivastava, Vandana
supporting information, p. 424 - 432 (2022/02/09)
A new green approach for the synthesis of amide through TBAI-catalyzed oxidative coupling of benzyl bromides with amine was developed in the presence of tert-butyl hydroperoxide (TBHP) as an oxidant. Various electron-donating and withdrawing groups containing benzyl bromides and various amines, were subjected to the reaction and transformed to the corresponding amide in good to excellent yields.
Catalytic N-Acylation of Cyclic Amines by Arylglyoxylic Acids via Radical-Radical Cross-Coupling
Bhadra, Sukalyan,Gupta, Aniket,Kumar Singh, Anupam,Rahaman, Ajijur
, p. 2198 - 2202 (2021/07/22)
A methodical mechanistic investigation allowed for the catalytic N-acylation of secondary cyclic amine counterparts by arylglyoxylic acids through radical-radical coupling. The reaction proceeds via a twofold SET-promoted Cu(I)/Cu(II) catalytic cycle under mild conditions. An analogous reaction variant allows for the N-acylation in a one-pot fashion directly starting from a secondary cyclic amine even in the presence of a second amine or hydroxy group.
Pd-Catalyst Containing a Hemilabile P,C-Hybrid Ligand in Amino Dicarbonylation of Aryl Halides for Synthesis of α-Ketoamides
Yang, Shu-Qing,Yao, Yin-Qing,Chen, Xiao-Chao,Lu, Yong,Zhao, Xiao-Li,Liu, Ye
, p. 1032 - 1041 (2021/05/07)
The amino dicarbonylation of aryl halides affording α-ketoamides with Pd catalysts is highly dependent on the stereoelectronic properties of the involved ligands. Ionic diphosphine ligand L4 can serve as precursor of a hemilabile P,C (phosphine, carbene)-hybrid ligand to form a stable Pd(II)-complex, Pd-L4. In contrast, analogues L1-L3 with a similar 1-(thiophen-3-yl)-benzimidazolyl skeleton behave as typical (mono/di)phosphines. The catalytic system resulting from the complexation of PdCl2(MeCN)2 and L4 exhibits good catalytic performance in terms of aryl iodides conversion (81-95%) and α-ketoamide selectivity (80-91%), as well as the available recyclability in the RTIL of [Bpy]BF4. The in situ FT-IR analysis reveals that the PdCl2(MeCN)2-L4 catalytic system favors the amino dicarbonylation toward α-ketoamides according to the proposed mechanism of cycle I, which involves two independent CO-insertion steps.
Deoxygenative hydroboration of primary, secondary, and tertiary amides: Catalyst-free synthesis of various substituted amines
An, Duk Keun,Jaladi, Ashok Kumar,Kim, Hyun Tae,Yi, Jaeeun
supporting information, (2021/11/17)
Transformation of relatively less reactive functional groups under catalyst-free conditions is an interesting aspect and requires a typical protocol. Herein, we report the synthesis of various primary, secondary, and tertiary amines through hydroboration of amides using pinacolborane under catalyst-free and solvent-free conditions. The deoxygenative hydroboration of primary and secondary amides proceeded with excellent conversions. The comparatively less reactive tertiary amides were also converted to the corresponding N,N-diamines in moderate yields under catalyst-free conditions, although alcohols were obtained as a minor product.
A practical and sustainable protocol for direct amidation of unactivated esters under transition-metal-free and solvent-free conditions
Chen, Cheng,Cheng, Hua,Du, Min-Chen,Qian, Liang,Qin, Xin,Sang, Wei,Yao, Wei-Zhong,Yuan, Ye,Zhang, Rui
supporting information, p. 3972 - 3982 (2021/06/17)
In this paper, a NaOtBu-mediated synthesis approach was developed for direct amidation of unactivated esters with amines under transition-metal-free and solvent-free conditions, affording a series of amides in good to excellent yields at room temperature. In particular, an environmentally friendly and practical workup procedure, which circumvents the use of organic solvents and chromatography in most cases, was disclosed. Moreover, the gram-scale production of representative products3a,3wand3auwas efficiently realized by applying operationally simple, sustainable and practical procedures. Furthermore, this approach was also applicable to the synthesis of valuable molecules such as moclobemide (a powerful antidepressant), benodanil and fenfuram (two commercial agricultural fungicides). These results demonstrate that this protocol has the potential to streamline amide synthesis in industry. Meanwhile, quantitative green metrics of all the target products were evaluated, implying that the present protocol is advantageous over the reported ones in terms of environmental friendliness and sustainability. Finally, additional experiments and computational calculations were carried out to elucidate the mechanistic insight of this transformation, and one plausible mechanism was provided on the basis of these results and the related literature reports.
Method for preparing amide from carboxylic acid under irradiation of blue light by taking iridium and cobalt complexes as catalysts
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Paragraph 0089-0090, (2021/05/12)
The invention relates to a method for preparing amide from carboxylic acid under the irradiation of blue light by taking iridium and cobalt complexes as catalysts, and belongs to the field of chemistry. The method comprises the following step of: by taking R substituted carboxylic acid and R1' and R2' substituted amines as raw materials, triphenylphosphine as a deoxidizing agent, [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 as a photocatalyst and Co(dmgH)(dmgH2)Cl2 as a metal complex catalyst, reacting in dichloromethane in an inert atmosphere and under the irradiation of blue light to obtain an amide compound, wherein R is an aryl group, a heteroaryl group, a protected amino group, a substituted alkyl group, a substituted aryl group or a substituted protected amino group, R1' is a hydrogen group, a substituted alkyl group, a phenyl group or a substituted phenyl group, and R2' is a hydrogen group, a substituted alkyl group, a phenyl group or a substituted phenyl group.
Ammonia-borane as a Catalyst for the Direct Amidation of Carboxylic Acids
Ramachandran, P. Veeraraghavan,Hamann, Henry J.
supporting information, p. 2938 - 2942 (2021/05/04)
Ammonia-borane serves as an efficient substoichiometric (10%) precatalyst for the direct amidation of both aromatic and aliphatic carboxylic acids. In situ generation of amine-boranes precedes the amidation and, unlike the amidation with stoichiometric amine-boranes, this process is facile with 1 equiv of the acid. This methodology has high functional group tolerance and chromatography-free purification but is not amenable for esterification. The latter feature has been exploited to prepare hydroxyl- and thiol-containing amides.
A Fast and General Route to Ketones from Amides and Organolithium Compounds under Aerobic Conditions: Synthetic and Mechanistic Aspects
Ghinato, Simone,Territo, Davide,Maranzana, Andrea,Capriati, Vito,Blangetti, Marco,Prandi, Cristina
supporting information, p. 2868 - 2874 (2021/01/21)
We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over-addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale-up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre-activated amides, as recommended.
