18370-11-1Relevant academic research and scientific papers
The Pd-catalyzed synthesis of difluoroethyl and difluorovinyl compounds with a chlorodifluoroethyl iodonium salt (CDFI)
Cao, Chengyao Kimmy,Chen, Chao,Ge, Chenxin,Niu, Yaru,Qu, Hongmei
supporting information, (2021/10/01)
Herein, we report a simple and efficient method for the direct installation of chlorodifluoroethyl group onto aromatic molecules of various aromatic amides with a new 2-chloro,2,2-difluoroethyl(mesityl)iodonium salt (CDFI). Moreover, the chlorodifluoroeth
Visible light-mediated synthesis of amides from carboxylic acids and amine-boranes
Chen, Xuenian,Kang, Jia-Xin,Ma, Yan-Na,Miao, Yu-Qi
supporting information, p. 3595 - 3599 (2021/06/06)
Here, a photocatalytic deoxygenative amidation protocol using readily available amine-boranes and carboxylic acids is described. This approach features mild conditions, moderate-to-good yields, easy scale-up, and up to 62 examples of functionalized amides with diverse substituents. The synthetic robustness of this method was also demonstrated by its application in the late-stage functionalization of several pharmaceutical molecules.
Trifluoroacetic Acid Hydroxylamine System as Organocatalyst Reagent in a One-Pot Salt Free Process for the Synthesis of Caprolactam and Amides of Industrial Interest
Manente,Pietrobon,Ronchin,Vavasori
, p. 3543 - 3549 (2021/03/30)
In this work we studied the reactivity of the Trifluoroacetic acid hydroxylamine system in the one step salt free synthesis of amides from ketones. A particular regards was paid to the caprolactam synthesis because of its industrial relevance. Synthesis, reactivity and characterization of the hydroxylamine trifluoroacetate is given. Fast oximation reaction of several ketones was gained at room temperature (1?h of reaction quantitative conversion for several ketones). In the same reactor, by raising the temperature at 383?K, the Beckmann rearrangement of the so obtained oximes is easily accomplished in the presence of three equivalent of TFA. The possibility of obtaining the trifluoroacetate of the hydroxylamine with a modified nitric acid hydrogenation reactions was verified, too. Reuse of solvent and trifluoroacetic acid is easily achieved by distillation. Graphical abstract: Salt free one-pot caprolactam and amides process catalyzed by CF3COOH, in the presence of NH2OH TFA as the oximation agent.[Figure not available: see fulltext.].
Catalytic asymmetric [3+2] cycloaddition of isomünchnones with methyleneindolinones
Feng, Xiaoming,Hu, Xinyue,Lin, Lili,Wang, Kaixuan,Xu, Chaoran,Zhou, Yuqiao
supporting information, p. 8917 - 8920 (2021/09/10)
An efficient enantioselective [3+2] cycloaddition of isomünchnones with methyleneindolinones that are generated by anin situintramolecular addition of the carbonyl group to rhodium carbenes is realized with a chiralN,N′-dioxide/Zn(ii) complex as a Lewis acid. A series of chiral oxa-bridged 3-spiropiperidines are obtained in high yields with excellent dr and excellent ee values.
Assemblies of 1,4-Bis(diarylamino)naphthalenes and Aromatic Amphiphiles: Highly Reducing Photoredox Catalysis in Water
Abe, Manabu,Akita, Munetaka,Chitose, Youhei,Hyodo, Yuki,Koike, Takashi,Takahashi, Keigo,Yoshizawa, Michito
supporting information, (2021/10/21)
Host-guest assemblies of a designed 1,4-bis(diarylamino)naphthalene and V-shaped aromatic amphiphiles consisting of two pentamethylbenzene moieties bridged by an m -phenylene unit bearing two hydrophilic side chains emerged as highly reducing photoredox catalysis systems in water. An efficient demethoxylative hydrogen transfer of Weinreb amides has been developed. The present supramolecular strategy permits facile tuning of visible-light photoredox catalysis in water.
Copper-Catalyzed Radical N-Demethylation of Amides Using N-Fluorobenzenesulfonimide as an Oxidant
Yi, Xuewen,Yi, Xuewen,Lei, Siyu,Liu, Wangsheng,Che, Fengrui,Yu, Chunzheng,Liu, Xuesong,Wang, Zonghua,Zhou, Xin,Zhang, Yuexia
supporting information, p. 4583 - 4587 (2020/05/05)
An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.
Rhodium-Catalyzed Electrooxidative C?H Olefination of Benzamides
Ackermann, Lutz,Struwe, Julia,Zhang, Yan
supporting information, p. 15076 - 15080 (2020/06/20)
Metal-catalyzed chelation-assisted C?H olefinations have emerged as powerful tools for the construction of functionalized alkenes. Herein, we describe the rhoda-electrocatalyzed C?H activation/alkenylation of arenes. The olefinations of challenging electron-poor benzamides were thus accomplished in a fully dehydrogenative fashion under electrochemical conditions, avoiding stoichiometric chemical oxidants, and with H2 as the only byproduct. This versatile alkenylation reaction also features broad substrate scope and used electricity as a green oxidant.
Dealkoxylation ofN-alkoxyamides without an external reductant driven by Pd/Al cooperative catalysis
Suzuki, Hirotsugu,Shiomi, Takahiro,Yoneoka, Kenji,Matsuda, Takanori
supporting information, p. 7545 - 7548 (2020/10/15)
Lewis acid-assisted palladium-catalysed dealkoxylation ofN-alkoxyamides has been developed. This reaction proceeded smoothly with a range ofN-alkoxyamides in the absence of an external reductant, thereby establishing a convenient and reductant-free protocol. In addition, a gram-scale reaction could be achieved. Preliminary mechanistic investigations indicated that β-hydrogen elimination from a palladium alkoxide intermediate generated an intramolecular hydride source.
Chemoselective Synthesis of Aryl Ketones from Amides and Grignard Reagents via C(O)-N Bond Cleavage under Catalyst-Free Conditions
Sureshbabu, Popuri,Azeez, Sadaf,Muniyappan, Nalluchamy,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
, p. 11823 - 11838 (2019/10/02)
Conversion of a wide range of N-Boc amides to aryl ketones was achieved with Grignard reagents via chemoselective C(O)-N bond cleavage. The reactions proceeded under catalyst-free conditions with different aryl, alkyl, and alkynyl Grignard reagents. α-Ketoamide was successfully converted to aryl diketones, while α,β-unsaturated amide underwent 1,4-addition followed by C(O)-N bond cleavage to provide diaryl propiophenones. N-Boc amides displayed higher reactivity than Weinreb amides with Grignard reagents. A broad substrate scope, excellent yields, and quick conversion are important features of this methodology.
Hydrogen Bond Directed ortho-Selective C?H Borylation of Secondary Aromatic Amides
Bai, Shao-Tao,Bheeter, Charles B.,Reek, Joost N. H.
supporting information, p. 13039 - 13043 (2019/07/31)
Reported is an iridium catalyst for ortho-selective C?H borylation of challenging secondary aromatic amide substrates, and the regioselectivity is controlled by hydrogen-bond interactions. The BAIPy-Ir catalyst forms three hydrogen bonds with the substrate during the crucial activation step, and allows ortho-C?H borylation with high selectivity. The catalyst displays unprecedented ortho selectivities for a wide variety of substrates that differ in electronic and steric properties, and the catalyst tolerates various functional groups. The regioselective C?H borylation catalyst is readily accessible and converts substrates on gram scale with high selectivity and conversion.
