135-00-2Relevant academic research and scientific papers
THE NAFION-H-CATALYZED ACYLATION OF THIOPHENE WITH ACID ANHYDRIDES
Konishi, Hisatoshi,Suetsugu, Kazuhiro,Okano, Tamon,Kiji, Jitsuo
, p. 957 - 958 (1982)
The reaction of thiophene with acyclic acid anhydrides in the presence of Nafion-H (fluorocarbon resin sulfonic acid) afforded the corresponding 2-acylthiophenes in moderate yields.Acylation with cyclic acid anhydrides gave only low yields, however.The Nafion-H catalyst could be reused for the acylation with a little loss of activity.
Heteroaryl manganese reagents: Direct preparation and reactivity studies
Rieke, Reuben D.,Suh, YoungSung,Kim, Seung-Hoi
, p. 5961 - 5964 (2005)
Direct preparation of various heteroaryl manganese reagents was performed by using highly active manganese (Mn*) and heteroaryl halides. The resulting organomanganese reagents were coupled with electrophiles such as aryl halides, vinyl halides, and benzoyl chlorides under mild reaction conditions. The corresponding coupling products were obtained in good yields.
Mechanochemical Solvent-Free Suzuki–Miyaura Cross-Coupling of Amides via Highly Chemoselective N?C Cleavage
Ma, Yangmin,Shao, Lei,Szostak, Michal,Wang, Ruihong,Zhang, Jin,Zhang, Pei
supporting information, (2022/01/04)
Although cross-coupling reactions of amides by selective N?C cleavage are one of the most powerful and burgeoning areas in organic synthesis due to the ubiquity of amide bonds, the development of mechanochemical, solid-state methods remains a major challe
Pd-Catalysed carbonylative Suzuki-Miyaura cross-couplings using Fe(CO)5under mild conditions: generation of a highly active, recyclable and scalable ‘Pd-Fe’ nanocatalyst
Zhu, Zhuangli,Wang, Zhenhua,Jian, Yajun,Sun, Huaming,Zhang, Guofang,Lynam, Jason M.,McElroy, C. Robert,Burden, Thomas J.,Inight, Rebecca L.,Fairlamb, Ian J. S.,Zhang, Weiqiang,Gao, Ziwei
supporting information, p. 920 - 926 (2021/02/09)
The dual function and role of iron(0) pentacarbonyl [Fe(CO)5] has been identified in gaseous CO-free carbonylative Suzuki-Miyaura cross-couplings, in which Fe(CO)5supplied COin situ, leading to the propagation of catalytically active Pd-Fe nanoparticles. Compared with typical carbonylative reaction conditions, CO gas (at high pressures), specialised exogenous ligands and inert reaction conditions were avoided. Our developed reaction conditions are mild, do not require specialised CO high pressure equipment, and exhibit wide functional group tolerance, giving a library of biaryl ketones in good yields.
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.
Organotellurium-catalyzed oxidative deoximation reactions using visible-light as the precise driving energy
Deng, Xin,Qian, Rongrong,Zhou, Hongwei,Yu, Lei
supporting information, p. 1029 - 1032 (2020/10/23)
Irradiated by visible light, the recyclable (PhTe)2-catalyzed oxidative deoximation reaction could occur under mild conditions. In comparison with the thermo reaction, the method employed reduced catalyst loading (1 mol% vs. 2.5 mol%), but afforded elevated product yields with expanded substrate scope. This work demonstrated that for the organotellurium-catalyzed reactions, visible light might be an even more precise driving energy than heating because it could break the Te–Te bond accurately to generate the active free radical catalytic intermediates without damaging the fragile substituents (e.g., heterocycles) of substrates. The use of O2 instead of explosive H2O2 as oxidant affords safer reaction conditions from the large-scale application viewpoint.
PhSe(O)OH/NHPI-catalyzed oxidative deoximation reaction using air as oxidant
Shi, Yaocheng,Wang, Feng,Yang, Chenggen,Yu, Lei
, (2021/09/06)
A novel oxidative deoximation method was developed in this article. Compared with the reported organoselenium-catalyzed oxidative deoximation reaction, this reaction employed N-hydroxyphthalimide (NHPI) as the co-catalyst, so that the oxidative deoximation reaction could utilize air as oxidant in the green DMC solvent under mild reaction conditions. Control experiments and X-ray photoelectron spectroscopy (XPS) analysis results indicated that NHPI was essential for activating the catalytic organoselenium species. It could accelerate the activation of molecular oxygen in air to promote the reaction process. The reaction can avoid metal residues in product and is of potential application values in pharmaceutical industry due to the transition metal-free process.
Novelmeta-benzothiazole and benzimidazole functionalised POCOP-Ni(ii) pincer complexes as efficient catalysts in the production of diarylketones
Castillo-García, Antonio A.,González-Sebastián, Lucero,Lomas-Romero, Leticia,Hernandez-Ortega, Simon,Toscano, Ruben A.,Morales-Morales, David
, p. 10204 - 10216 (2021/06/18)
The synthesis of four novel non-symmetric Ni(ii)-POCOP pincer complexesmeta-functionalized with either benzothiazole or benzimidazole at the central aryl ring is described. All complexes were fully characterised in solution by various analytical techniques and the molecular structures in the solid state of complexes1b,2aand2bwere unequivocally determined by single crystal X-ray diffraction analysis. In addition, the Ni(ii)-POCOP pincer complexes were efficiently used as catalysts in the synthesis of diarylketones by cross-coupling reactions of functionalized benzaldehydes and boronic acid derivatives under relatively mild conditions. An important aspect of this transformation is the dependence on the steric properties of the donor groups (OPR2) of the pincer ligands, the more active compounds having the phosphinitos bearing isopropyl groups (1aand2a) than those containingtert-butyl substituents (1band2b).
Visible light-driven direct synthesis of ketones from aldehydes via C[sbnd]H bond activation using NiCu nanoparticles adorned on carbon nano onions
Heydari, Akbar,Khorsandi, Zahra,Metkazini, S. Fatemeh Mohammadi,Varma, Rajender S.
, (2021/11/09)
An efficient, straightforward and high yield synthetic approach is described for the direct synthesis of diaryl ketones via the C[sbnd]H bond activation of aldehydes using NiCu nanoparticles adorned on carbon nano onions as an efficient heterogeneous catalyst under the irradiation of a mercury-vapor lamp (400 w) via simple workup. This C[sbnd]H bond activation reaction appears simple and convenient with a wide substrate scope in view of its excellent synthesis prowess as illustrated in the preparation of new-approved anti-Alzheimer and anti-HIV medicinal compounds under greener and mild reaction conditions; catalyst could be recycled and reused five times without any loss of catalytic activity.
Asymmetric Transfer Hydrogenation of Aryl Heteroaryl Ketones using Noyori-Ikariya Catalysts
Zheng, Ye,Martinez-Acosta, Jaime A.,Khimji, Mohammed,Barbosa, Luiz C. A.,Clarkson, Guy J.,Wills, Martin
, p. 4384 - 4391 (2021/08/23)
A range of ketones flanked by a combination of an aromatic and a heterocyclic ring (furan, thiophene, N-methylimidazole) were reduced under asymmetric transfer hydrogenation (ATH) conditions. Using a range of [(arene)Ru(TsDPEN)Cl] precatalysts, including tethered derivatives, the reduction enantioselectivity was high (up to 99 % ee) in cases where the aromatic ring contained an ortho-substituent. The enantioselectivity is influenced by a combination of steric and electronic factors which for the furan and thiophene series, follow literature precedents. In the case of the N-methylimidazole-containing ketones, an unexpected switch in enantioselectivity took place upon variation of the opposing aromatic group. Pyrrole- containing ketones were resistant to reduction. This study demonstrates the asymmetric transfer hydrogenation (ATH) of a range of hindered heterocyclic ketones, in high conversion and ee, using Noyori-Ikariya catalysts.
