75490-38-9Relevant academic research and scientific papers
Enantioselective Copper(I)/Chiral Phosphoric Acid Catalyzed Intramolecular Amination of Allylic and Benzylic C?H Bonds
Ye, Liu,Tian, Yu,Meng, Xiang,Gu, Qiang-Shuai,Liu, Xin-Yuan
supporting information, p. 1129 - 1133 (2019/12/12)
Radical-involved enantioselective oxidative C?H bond functionalization by a hydrogen-atom transfer (HAT) process has emerged as a promising method for accessing functionally diverse enantioenriched products, while asymmetric C(sp3)?H bond amination remains a formidable challenge. To address this problem, described herein is a dual CuI/chiral phosphoric acid (CPA) catalytic system for radical-involved enantioselective intramolecular C(sp3)?H amination of not only allylic positions but also benzylic positions with broad substrate scope. The use of 4-methoxy-NHPI (NHPI=N-hydroxyphthalimide) as a stable and chemoselective HAT mediator precursor is crucial for the fulfillment of this transformation. Preliminary mechanistic studies indicate that a crucial allylic or benzylic radical intermediate resulting from a HAT process is involved.
Remote Directed Isocyanation of Unactivated C(sp3)-H Bonds: Forging Seven-Membered Cyclic Ureas Enabled by Copper Catalysis
Zhang, Hongwei,Tian, Peiyuan,Ma, Lishuang,Zhou, Yulu,Jiang, Cuiyu,Lin, Xufeng,Xiao, Xiao
supporting information, p. 997 - 1002 (2020/02/15)
Reported herein is an unprecedented copper-catalyzed site-selective ?-C(sp3)-H bonds activation of aliphatic sulfonamides for constructing the synthetically useful seven-membered N-heterocycles. A key to success is the use of in-situ-formed amide radicals, to activate the inert C(sp3)-H bond, and inexpensive TMSNCO, as a coupling reagent under mild conditions. To the best of our knowledge, this represents the first use of alkylamine derivatives as a five-membered synthon to prepare a seven-membered N-heterocycles.
Metal-Free-Catalyzed Synthesis of Allyl Nitriles via Csp2-Csp3 Coupling between Olefins and Azobis (Alkyl-carbonitrile)
Cao, Zhong-Zhong,Nie, Zhiwen,Yang, Tonglin,Su, Miaodong,Li, Hui,Luo, Wei-Ping,Liu, Qiang,Guo, Can-Cheng
, p. 3287 - 3296 (2020/03/23)
The metal-free-catalyzed synthesis of allyl nitriles from Csp2-Csp3 coupling between olefins and azobis was carried out. Key on this work was that the synthesis of allyl nitriles directly using olefin as a start
Visible-Light-Mediated Remote γ-C(sp3)-H Functionalization of Alkylimidates: Synthesis of 4-Iodo-3,4-dihydropyrrole Derivatives
Kumar, Yogesh,Jaiswal, Yogesh,Kumar, Amit
supporting information, p. 4964 - 4969 (2018/08/24)
An efficient and environmentally friendly synthetic approach toward functionalized dihydropyrrole derivatives is reported. The developed protocol proceeds via chemoselective intramolecular N-C bond formation of alkylimidates through 1,5-hydrogen atom transfer from in situ generated imidate N-radicals. The major advantage of this designed strategy lies in the choice of starting materials, mild reaction conditions, high chemo- and diastereoselectivity, clean source of energy, and good functional group tolerance. Further, 4-iododihydropyrroles could be easily transformed into a variety of useful derivatives.
Anodic benzylic C(sp3)-H amination: Unified access to pyrrolidines and piperidines
Herold, Sebastian,Bafaluy, Daniel,Mu?iz, Kilian
supporting information, p. 3191 - 3196 (2018/07/29)
An electrochemical aliphatic C-H amination strategy was developed to access the important heterocyclic motifs of pyrrolidines and piperidines within a uniform reaction protocol. The mechanism of this unprecedented C-H amination strategy involves anodic C-H activation to generate a benzylic cation, which is efficiently trapped by a nitrogen nucleophile. The applicability of the process is demonstrated for 40 examples comprising both 5- and 6-membered ring formations.
An Iodine-Catalyzed Hofmann-L?ffler Reaction
Martínez, Claudio,Mu?iz, Kilian
supporting information, p. 8287 - 8291 (2015/07/07)
Iodine reagents have been identified as economically and ecologically benign alternatives to transition metals, although their application as molecular catalysts in challenging C-H oxidation reactions has remained elusive. An attractive iodine oxidation catalysis is now shown to promote the convenient conversion of carbon-hydrogen bonds into carbon-nitrogen bonds with unprecedented complete selectivity. The reaction proceeds by two interlocked catalytic cycles comprising a radical chain reaction, which is initiated by visible light as energy source. This unorthodox synthetic strategy for the direct oxidative amination of alkyl groups has no biosynthetic precedence and provides an efficient and straightforward access to a general class of saturated nitrogenated heterocycles.
Photoinduced, Copper-Catalyzed Carbon-Carbon Bond Formation with Alkyl Electrophiles: Cyanation of Unactivated Secondary Alkyl Chlorides at Room Temperature
Ratani, Tanvi S.,Bachman, Shoshana,Fu, Gregory C.,Peters, Jonas C.
supporting information, p. 13902 - 13907 (2016/01/15)
We have recently reported that, in the presence of light and a copper catalyst, nitrogen nucleophiles such as carbazoles and primary amides undergo C-N coupling with alkyl halides under mild conditions. In the present study, we establish that photoinduced, copper-catalyzed alkylation can also be applied to C-C bond formation, specifically, that the cyanation of unactivated secondary alkyl chlorides can be achieved at room temperature to afford nitriles, an important class of target molecules. Thus, in the presence of an inexpensive copper catalyst (CuI; no ligand coadditive) and a readily available light source (UVC compact fluorescent light bulb), a wide array of alkyl halides undergo cyanation in good yield. Our initial mechanistic studies are consistent with the hypothesis that an excited state of [Cu(CN)2]- may play a role, via single electron transfer, in this process. This investigation provides a rare example of a transition metal-catalyzed cyanation of an alkyl halide, as well as the first illustrations of photoinduced, copper-catalyzed alkylation with either a carbon nucleophile or a secondary alkyl chloride.
Copper catalyzed decarboxylative alkynylation of quaternary α-cyano acetate salts
Feng, Yi-Si,Xu, Zhong-Qiu,Mao, Long,Zhang, Feng-Feng,Xu, Hua-Jian
, p. 1472 - 1475 (2013/06/27)
Cu-catalyzed decarboxylative alkynylation of quaternary α-cyano acetate salts with alkynyl bromides and alkynyl chlorides is described. This new reaction can be used for preparing functionalized butynenitrile derivatives.
Copper-catalyzed benzylic C-H oxygenation under an oxygen atmosphere via N-H imines as an intramolecular directing group
Zhang, Line,Ang, Gim Yean,Chiba, Shunsuke
supporting information; experimental part, p. 1622 - 1625 (2011/05/05)
Copper-catalyzed benzylic C-H oxygenation under an oxygen atmosphere was developed starting from carbonitriles and Grignard reagents via N-H imine intermediates. The present process is characterized by the following two-step sequence in a one-pot manner: (1) addition of Grignard reagents to carbonitriles to form N-H imines and (2) benzylic C-H oxygenation (C=O bond formation) triggered by 1,5-hydrogen atom transfer with transient iminyl copper species.
Novel selective anti-androgens with a diphenylpentane skeleton
Maruyama, Keisuke,Noguchi-Yachide, Tomomi,Sugita, Kazuyuki,Hashimoto, Yuichi,Ishikawa, Minoru
scheme or table, p. 6661 - 6666 (2010/12/19)
We have proposed a multi-template approach for drug development, focusing on similar fold structures of proteins, and have effectively generated lead compounds for several drug targets. Modification of these polypharmacological lead compounds is then needed to generate target-selective compounds. In the work presented here, we aimed at separation of the anti-androgen activity and vitamin D activity of previously identified diphenylpentane lead compounds. Based on the determined X-ray crystal structures of androgen receptor and vitamin D receptor, bulky substituents were introduced at the t-butyl group in the lead compounds 2 and 3. As a result of this structural development, we obtained 16c, which exhibits more potent anti-androgen activity (IC 50: 0.13 μM) than clinically used anti-androgen bicalutamide (IC50: 0.67 μM) with 30-fold selectivity over vitamin D activity. This result indicates that lead compounds obtained via the multi-template approach can indeed be structurally modified to generate target-selective compounds.
