97637-73-5Relevant articles and documents
Direct Synthesis of α-Amino Nitriles from Sulfonamides via Base-Mediated C-H Cyanation
Shi, Shasha,Yang, Xianyu,Tang, Man,Hu, Jiefeng,Loh, Teck-Peng
, p. 4018 - 4022 (2021/05/26)
Herein, we disclose a transition-metal-free reaction system that enables α-cyanation of sulfonamides through C-H bond cleavage for the preparation of α-amino nitriles, including difficult-to-access all-alkyl α-tertiary scaffolds. More than 50 substrate examples prove a wide functional group tolerance. Additionally, its synthetic practicality is highlighted by gram-scalability and the late-stage modification of natural compounds. Mechanistic experiments suggest that this process involves in situ formation of an imine intermediate via base-promoted elimination of HF.
Development of a CuCl/phosphine system to catalyze phenylation and methylation of N-tosyl aldimines with phenylboronic andmethylboronic acids
Ashouri, Akram,Nasiri, Behzad,Pourian, Somayeh,Samadi, Saadi,Zamani, Hossein
, p. 575 - 581 (2021/01/13)
The addition of phenylboronic and methylboronic acids to activated aromatic aldimines was demonstrated in the presence of copper(I)-phosphine complexes. The desired products were obtained using copper chloride/phosphine, and potassium fluoride in under toluene reflux, in moderate-to-good yield and a suitable reaction time.
Site-Selective Electrochemical Benzylic C?H Amination
Hou, Zhong-Wei,Liu, Ding-Jin,Xiong, Peng,Lai, Xiao-Li,Song, Jinshuai,Xu, Hai-Chao
supporting information, p. 2943 - 2947 (2020/12/11)
C?H/N-H cross-coupling is an ideal strategy to synthesize various amines but remains challenging owing to the requirement for sacrificial chemical oxidants and the difficulty in controlling the regio- and chemo-selectivity. Herein we report a site-selective electrochemical amination reaction that can convert benzylic C?H bonds into C-N linkages via H2 evolution without need for external oxidants or metal catalysts. The synthetic strategy involves anodic cleavage of benzylic C?H to form a carbocation intermediate, which is then trapped with an amine nucleophile leading to C?N bond formation. Key to the success is to include HFIP as a co-solvent to modulate the oxidation potentials of the alkylbenzene substrate and the aminated product to avoid overoxidation of the latter.
Halogen-Bond-Induced Consecutive Csp3-H Aminations via Hydrogen Atom Transfer Relay Strategy
Alom, Nur-E,Ariyarathna, Jeewani P.,Bassiouni, Omar H.,Kaur, Navdeep,Kennell, Maureen L.,Li, Wei,Wu, Fan
, p. 2135 - 2140 (2020/04/09)
The utilization of a halogen bond in a number of chemical fields is well-known. Surprisingly, the incorporation of this useful noncovalent interaction in chemical reaction engineering is rare. We disclose here an uncommon use of halogen bonding to induce intermolecular Csp3-H amination while enabling a hydrogen atom transfer relay strategy to access privileged pyrrolidine structures directly from alkanes. Mechanistic studies support the presence of multiple halogen bond interactions at distinct reaction stages.
Redox Self-Adaptation of a Nitrene Transfer Catalyst to the Substrate Needs
Gouré, Eric,Senthilnathan, Dhurairajan,Coin, Guillaume,Albrieux, Florian,Avenier, Frédéric,Dubourdeaux, Patrick,Lebrun, Colette,Maldivi, Pascale,Latour, Jean-Marc
supporting information, p. 4305 - 4309 (2017/04/04)
The development of iron catalysts for carbon–heteroatom bond formation, which has attracted strong interest in the context of green chemistry and nitrene transfer, has emerged as the most promising way to versatile amine synthetic processes. A diiron system was previously developed that proved efficient in catalytic sulfimidations and aziridinations thanks to an FeIIIFeIV active species. To deal with more demanding benzylic and aliphatic substrates, the catalyst was found to activate itself to a FeIIIFeIVL. active species able to catalyze aliphatic amination. Extensive DFT calculations show that this activation event drastically enhances the electron affinity of the active species to match the substrates requirements. Overall this process consists in a redox self-adaptation of the catalyst to the substrate needs.
Iron-catalyzed efficient intermolecular amination of C(sp3)-H bonds with bromamine-T as nitrene source
Wang, Haiyu,Li, Yuxi,Wang, Zhiming,Lou, Jun,Xiao, Yuling,Qiu, Guofu,Hu, Xianming,Altenbach, Hans-Josef,Liu, Peng
, p. 25287 - 25290 (2014/07/07)
[Fe(N4Py)(CH3CN)](ClO4)2 can efficiently catalyze intermolecular nitrene insertion of sp3 C-H bonds with bromamine-T as the nitrene source, forming the desired tosylprotected amines with NaBr as the by-product.
Fe2(SO4)3·xH2O on silica: An efficient and low-cost catalyst for the direct nucleophilic substitution of alcohols in solvent-free conditions
Li, Lingjun,Zhu, Anlian,Zhang, Yuqin,Fan, Xincui,Zhang, Guisheng
, p. 4286 - 4291 (2014/01/17)
Fe2(SO4)3·xH2O on silica has been found to be a novel efficient catalyst for the direct nucleophilic substitution of alcohols in solvent-free conditions. In this reaction system, the alcohols can react with various nucleophilic reagents for the convenient construction of C-C bonds and C-N bonds with the benefits of high conversion, no requirement to use excessive amounts of the nucleophile, only a catalytic amount of iron catalyst required, solvent-free and benign reaction conditions, and the feasible reusability of the catalyst.
Nonheme iron-mediated amination of C(sp3)-H bonds. Quinquepyridine-supported iron-imide/nitrene intermediates by experimental studies and DFT calculations
Liu, Yungen,Guan, Xiangguo,Wong, Ella Lai-Ming,Liu, Peng,Huang, Jie-Sheng,Che, Chi-Ming
supporting information, p. 7194 - 7204 (2013/06/27)
The 7-coordinate complex [Fe(qpy)(MeCN)2](ClO4) 2 (1, qpy = 2,2′:6′,2″:6″, 2′′′:6′′′,2′′′′- quinquepyridine) is a highly active nonheme iron catalyst for intra- and intermolecular amination of C(sp3)-H bonds. This complex effectively catalyzes the amination of limiting amounts of not only benzylic and allylic C(sp3)-H bonds of hydrocarbons but also the C(sp3)-H bonds of cyclic alkanes and cycloalkane/linear alkane moieties in sulfamate esters, such as those derived from menthane and steroids cholane and androstane, using PhI=NR or "PhI(OAc)2 + H2NR" [R = Ts (p-toluenesulfonyl), Ns (p-nitrobenzenesulfonyl)] as nitrogen source, with the amination products isolated in up to 93% yield. Iron imide/nitrene intermediates [Fe(qpy)(NR)(X)]n+ (CX, X = NR, solvent, or anion) are proposed in these amination reactions on the basis of experimental studies including ESI-MS analysis, crossover experiments, Hammett plots, and correlation with C-H bond dissociation energies and with support by DFT calculations. Species consistent with the formulations of [Fe(qpy)(NTs)2] 2+ (CNTs) and [Fe(qpy)(NTs)]2+ (C) were detected by high-resolution ESI-MS analysis of the reaction mixture of 1 with PhI=NTs (4 equiv). DFT calculations revealed that the reaction barriers for H-atom abstraction of cyclohexane by the ground state of 7-coordinate C NTs and ground state of C are 15.3 and 14.2 kcal/mol, respectively, in line with the observed high activity of 1 in catalyzing the C-H amination of alkanes under mild conditions.
Reduction of sulfonylimines with raney nickel
Ruano, Jose Luis Garca,Fernandez-Salas, Jose A.,Maestro, M. Carmen,Parra, Alejandro
, p. 198 - 207,10 (2020/09/02)
Raney-Ni/EtOH reduction of different N-sulfonylimines provides a new entry for synthesizing sulfonamides in good yields under mild conditions. This protocol, which does not require additional hydrogen, constitutes a cheap, safe, and easy-to-handle alterna
Transition-metal-free benzylic C-H bond intermolecular amination utilizing chloramine-T and I2
Takeda, Youhei,Hayakawa, Junpei,Yano, Kazuki,Minakata, Satoshi
supporting information, p. 1672 - 1674 (2013/02/23)
An intermolecular benzylic C-H bond amination utilizing the combination of chloramine-T and I2 without the aid of transition-metal catalysts has been developed. The reaction was found applicable to a variety of benzene-substituted alkanes, as w
