34058-62-3Relevant articles and documents
Nickel-catalyzed aromatic C-H alkylation with secondary or tertiary alkyl-bromine bonds for the construction of indolones
Liu, Chao,Liu, Dong,Zhang, Wei,Zhou, Liangliang,Lei, Aiwen
, p. 6166 - 6169 (2013)
A nickel-catalyzed aromatic C-H alkylation with tertiary or secondary alkyl-Br bonds for the construction of indolones was demonstrated. Various functional groups were well tolerated. Moreover, the challenging secondary alkyl bromides were well introduced in this transformation. Radical trapping and photocatalysis conditions exhibited that it is most likely to be a radical process for this aromatic C-H alkylation.
Hydroarylation of Activated Alkenes Enabled by Proton-Coupled Electron Transfer
Liu, Zhaosheng,Zhong, Shuai,Ji, Xiaochen,Deng, Guo-Jun,Huang, Huawen
, p. 4422 - 4429 (2021/05/06)
Hydroarylation of alkenes has been demonstrated to be an atom-economic approach to access functionalized arenes from easily accessible raw materials. Herein, we report a visible light-induced photocatalytic system that enables intramolecular hydroarylation of N-arylacrylamides with high 5-exo-trig selectivity through robust proton-coupled electron transfer (PCET). This mild hydroarylation protocol provides a straightforward entry to structurally valuable oxindoles and complements previously established 6-endo-trig cyclization by photochemical triplet energy transfer (TET).
Enantioselective Synthesis of C?N Axially Chiral N-Aryloxindoles by Asymmetric Rhodium-Catalyzed Dual C?H Activation
Li, Honghe,Yan, Xiaoqiang,Zhang, Jitan,Guo, Weicong,Jiang, Jijun,Wang, Jun
, p. 6732 - 6736 (2019/04/17)
The first enantioselective Satoh–Miura-type reaction is reported. A variety of C?N axially chiral N-aryloxindoles have been enantioselectively synthesized by an asymmetric rhodium-catalyzed dual C?H activation reaction of N-aryloxindoles and alkynes. High yields and enantioselectivities were obtained (up to 99 % yield and up to 99 % ee). To date, it is also the first example of the asymmetric synthesis of C?N axially chiral compounds by such a C?H activation strategy.
Iron-Enhanced Reactivity of Radicals Enables C-H Tertiary Alkylations for Construction of Functionalized Quaternary Carbons
Yamane, Yu,Yoshinaga, Kohei,Sumimoto, Michinori,Nishikata, Takashi
, p. 1757 - 1762 (2019/02/14)
Iron is one of the most attractive catalysts, especially for aromatic C-H functionalizations. However, stoichiometric amounts of oxidants and strong carbanions are required, and C-H tertiary alkylation, especially with electron-deficient alkyl groups, is unexplored. In this paper, we describe the development of iron-catalyzed selective C-H tertiary alkylations with heteroaromatics, in which an iron salt acts as a single-electron source and enhances the reactivity of a tertiary alkyl radical generated from α-bromocarbonyl compounds. Our established methodology was demonstrated in the efficient synthesis of various quaternary carbon atoms under very simple conditions.
A tethering directing group strategy for ruthenium-catalyzed intramolecular alkene hydroarylation
Kilaru, Praveen,Acharya, Sunil P.,Zhao, Pinjing
supporting information, p. 924 - 927 (2018/02/07)
We report a new catalyst design for N-heterocycle synthesis that utilizes an alkene-tethered amide moiety as a directing group for aromatic C-H activation. This tethering directing group strategy is demonstrated in a ruthenium-catalyzed intramolecular alk
DMF-Promoted Redox-Neutral Ni-Catalyzed Intramolecular Hydroarylation of Alkene with Simple Arene
Lu, Ke,Han, Xing-Wang,Yao, Wei-Wei,Luan, Yu-Xin,Wang, Yin-Xia,Chen, Hao,Xu, Xue-Tao,Zhang, Kun,Ye, Mengchun
, p. 3913 - 3917 (2018/05/22)
A redox-neutral Ni-catalyzed intramolecular hydroarylation of alkene with simple arene has been developed, in which DMF played a proton shuttle role in facilitating the intramolecular coupling, avoiding the use of additional reductants and oxidants. A series of oxindoles with a quaternary center were obtained in up to 99% yield.
Copper-catalyzed direct alkylation of heteroarenes
Theunissen, Cédric,Wang, Jianjun,Evano, Gwilherm
, p. 3465 - 3470 (2017/07/11)
An efficient and broadly applicable process is reported for the direct alkylation of C-H bonds in heteroarenes, privileged scaffolds in many areas of science. This reaction is based on the copper-catalyzed addition of alkyl radicals generated from activated secondary and tertiary alkyl bromides to a wide range of arenes, including furans, thiophenes, pyrroles, and their benzo-fused derivatives, as well as coumarins and quinolinones.
Copper-Salt-Promoted Carbocyclization Reactions of α-Bromo- N -arylacylamides
Chuang, Che-Ping,Chen, Ying-Yu,Chuang, Tsung-Han,Yang, Cheng-Hao
, p. 1273 - 1284 (2017/03/11)
A mild and convenient synthetic method for oxindoles and α-arylacylamides bearing an all carbon quaternary stereocenter from the readily available α-bromo-N-arylacylamides has been developed. This Cu(acac)2/Phen-promoted radical cyclization rea
Synthesis of indolones via radical cyclization of N-(2-halogenoalkanoyl)- substituted anilines
Nishio, Takehiko,Iseki, Kyoko,Araki, Norihito,Miyazaki, Takenori
, p. 35 - 41 (2007/10/03)
The radical reactions of N-(2-halogenoalkanoyl)-substituted anilines (anilides) of type 1 have been investigated under various conditions. Treatment of compounds 1a-1o with Bu3SnH in the presence of (2,2′-azobis(isobutyronitrile) (AIBN) afforded a mixture of the indolones (oxindoles) 2a-2o and the reduction products 5a-5o (Table 1). In contrast, the N-unsubstituted anilides 1p-1s, 1u, and 1v gave the corresponding reduction products exclusively (Table 1). Similar results were obtained by treatment of 1 with Ni powder (Table 2) or wth Et3B (Table 3). Anilides with longer N-(phenylalkyl) chains such as 6 and 7 were inert towards radical cyclization, with the exception of N-benzyl-2-bromo-N,2-dimethylpropanamide (6b), which, upon treatment with Ni powder in i-PrOH, afforded the cyclized product 9b in low yield (Table 4). Upon irradiation, the extended anilides 6, 7, 10, and 11 yielded the corresponding dehydrobromination products exclusively (Table 5).
