612-98-6Relevant academic research and scientific papers
One-Pot Tandem ortho-Naphthoquinone-Catalyzed Aerobic Nitrosation of N-Alkylanilines and Rh(III)-Catalyzed C-H Functionalization Sequence to Indole and Aniline Derivatives
Si, Tengda,Kim, Hun Young,Oh, Kyungsoo
, p. 1152 - 1163 (2021/01/14)
The nitroso group served as a traceless directing group for the C-H functionalization of N-alkylanilines, ultimately removed after functioning either as an internal oxidant or under subsequent reducing conditions. The unique ability of o-NQ catalysts to aerobically oxidize the N-alkylanilines without using solvents and stoichiometric amounts of oxidants has rendered the new opportunity to develop the telescoped catalyst systems without a need for directly handling the hazardous N-nitroso compounds.
Three-Component Couplings among Heteroarenes, Difluorocyclopropenes, and Water via C-H Activation
Liu, Xuexin,Chen, Jian,Yang, Chunyan,Wu, Zhouping,Li, Zhiyang,Shi, Yuesen,Huang, Tianle,Yang, Zhongzhen,Wu, Yong
supporting information, p. 6831 - 6835 (2021/09/08)
Three-component couplings have been realized for efficiently constructing various nitrogen-containing skeletons via C-H activation, where difluorocyclopropenes have been first identified as coupling partners. Many substrates including sp2 and sp3 C-H substrates were well tolerated, furnishing the corresponding products in good yields. Furthermore, a catalyst-dependent reaction was also developed, enabling divergent construction of two different frameworks. The application value of these reactions was demonstrated in gram-scale experiments with as little as 1 mol % catalyst.
Rhodium-catalyzed tandem acylmethylation/annulation ofN-nitrosoanilines with sulfoxonium ylides for the synthesis of substituted indazoleN-oxides
Cui, Xin-F,Huang, Guo-Sh
supporting information, p. 4014 - 4018 (2020/06/09)
An atom-economical protocol for synthesizing indazoleN-oxides from readily availableN-nitrosoanilines and sulfoxonium ylides through the rhodium(iii)-catalyzed C-H activation and cyclization reaction is described here. This protocol employs nitroso as a traceless directing group. The transformation features powerful reactivity, tolerates various functional groups, and proceeds with moderate to good yields under an ambient atmosphere, providing a straightforward approach to access structurally diverse and valuable indazoleN-oxide derivatives. Importantly, this new annulation process represents a hitherto unobserved reactivity pattern for theN-nitroso group.
Rh(iii)-catalyzed, hydrazine-directed C-H functionalization with 1-alkynylcyclobutanols: A new strategy for 1: H -indazoles
Zhang, Lei,Chen, Junyu,Chen, Xiahe,Zheng, Xiangyun,Zhou, Jian,Zhong, Tianshuo,Chen, Zhiwei,Yang, Yun-Fang,Jiang, Xinpeng,She, Yuan-Bin,Yu, Chuanming
supporting information, p. 7415 - 7418 (2020/07/15)
Rh(iii)-catalyzed coupling of phenylhydrazines with 1-alkynylcyclobutanols was realized through a hydrazine-directed C-H functionalization pathway. This [4+1] annulation, based on the cleavage of a Csp-Csp triple bond in alkynylcyclobutanol, provides a new pathway to prepare diverse 1H-indazoles under mild reaction conditions. This journal is
Substrate promiscuity of ortho-naphthoquinone catalyst: Catalytic aerobic amine oxidation protocols to deaminative cross-coupling and n-nitrosation
Kim, Hun Young,Oh, Kyungsoo,Si, Tengda
, p. 9216 - 9221 (2019/10/08)
ortho-Naphthoquinone-based organocatalysts have been identified as versatile aerobic oxidation catalysts. Primary amines were readily cross-coupled with primary nitroalkanes via deaminative pathway to give nitroalkene derivatives in good to excellent yields. Secondary and tertiary amines were inert to ortho-naphthoquinone catalysts; however, secondary nitroalkanes were readily converted by ortho-naphthoquinone catalysts to the corresponding nitrite species that in situ oxidized the amines to the corresponding N-nitroso compounds. Without using harsh oxidants in a stoichiometric amount, the present catalytic aerobic oxidation protocol utilizes the substrate promiscuity feature to provide a facile access to amine oxidation products under mild reaction conditions.
Rhodium(iii)-catalyzed indole synthesis at room temperature using the transient oxidizing directing group strategy
Shang, Yaping,Jonnada, Krishna,Yedage, Subhash Laxman,Tu, Hua,Zhang, Xiaofeng,Lou, Xin,Huang, Shijun,Su, Weiping
supporting information, p. 9547 - 9550 (2019/08/15)
Rh-catalyzed reactions of N-alkyl anilines with internal alkynes at room temperature have been developed using an in situ generated N-nitroso group as a transient oxidizing directing group. Due to mild reaction conditions, this method enabled synthesis of a broad range of N-alkyl indoles, including even two indole-based medicinal compounds. Our work disclosed the feasibility of the transient oxidizing directing group strategy in C-H functionalization reactions, which possesses the potential to enhance overall step-economy and impart new reactivity patterns to substrates.
Cp?Rh(iii) catalyzed: Ortho -halogenation of N -nitrosoanilines by solvent-controlled regioselective C-H functionalization
Peng, Qiujun,Hu, Jian,Huo, Jiyou,Yuan, Hongshun,Xu, Lanting,Pan, Xianhua
supporting information, p. 4471 - 4481 (2018/06/29)
We present a novel, efficient, and regioselective method for the rhodium-catalyzed direct C-H ortho-halogenation of anilines that involves a removable N-nitroso directing group. This method featured mild reaction conditions, wide substrate scope, good functional group tolerance and satisfactory yields. To maintain the high ortho-regioselectivity and conversion, increasing the steric hindrance of the solvent was critical. Preliminary mechanistic studies suggest that C-H activation may be involved in the rate-determining step.
Rhodium-catalyzed oxidative C-H/C-H cross-coupling of aniline with heteroarene: N-nitroso group enabled mild conditions
He, Shuang,Tan, Guangying,Luo, Anping,You, Jingsong
supporting information, p. 7794 - 7797 (2018/07/25)
The development of transition metal-catalyzed oxidative C-H/C-H cross-coupling between two (hetero)arenes to forge aryl-heteroaryl motifs under mild conditions is an appealing yet challenging task. Herein, we disclose a rhodium-catalyzed oxidative C-H/C-H cross-coupling reaction of an N-nitrosoaniline with a heteroarene under mild conditions. The judicious choice of the N-nitroso group as a directing group enables heightened reactivity. The coupled products could be transformed expediently to (2-aminophenyl)heteroaryl skeletons.
Rhodium(III)-Catalyzed Directed C?H Amidation of N-Nitrosoanilines and Subsequent Formation of 1,2-Disubstituted Benzimidazoles
Chen, Yanyu,Zhang, Rong,Peng, Qiujun,Xu, Lanting,Pan, XianHua
supporting information, p. 2804 - 2808 (2017/10/20)
An efficient rhodium-catalyzed direct C?H amidation of N-nitrosoanilines with 1,4,2-dioxazol-5-ones as amidating agents has been developed. This method featured mild reaction conditions, a wide substrate scope and satisfactory yields. Besides, the amidated products could be readily converted to pharmaceutically valuable 1,2-disubstituted benzimidazoles via an HCl-mediated deprotection/cyclization process in one pot.
An efficient synthesis of: N -nitrosamines under solvent, metal and acid free conditions using tert -butyl nitrite
Chaudhary, Priyanka,Gupta, Surabhi,Muniyappan, Nalluchamy,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
supporting information, p. 2323 - 2330 (2016/05/19)
Synthesis of various N-nitroso compounds from secondary amines is reported using tert-butyl nitrite (TBN) under solvent free conditions. Broad substrate scope, metal and acid free conditions, easy isolation procedure and excellent yields are few important features of this methodology. The acid labile protecting groups such as tert-butyldimethylsilyl (TBDMS) and tert-butyloxycarbonyl (Boc) as well as sensitive functional groups such as phenols, olefins and alkynes are found to be stable under the standard reaction conditions. Besides N-nitrosation, TBN is also found to be an efficient reagent in few other transformations including aryl hydrazines to aryl azides and primary amides to carboxylic acids under mild conditions.
