The Experts below are selected from a list of 117534 Experts worldwide ranked by ideXlab platform
Chungu Xia - One of the best experts on this subject based on the ideXlab platform.
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metal free regioselective c 3 nitration of quinoline n oxides with tert butyl nitrite
ChemInform, 2015Co-Authors: Jingjing Zhao, Chungu XiaAbstract:Various 3-nitroquinoline N-oxides are directly, eco-friendly, and regioselectively obtained using tert-butyl nitrite as both the nitro source and oxidant via a free Radical Process.
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metal free regioselective c 3 nitration of quinoline n oxides with tert butyl nitrite
RSC Advances, 2015Co-Authors: Jingjing Zhao, Chungu XiaAbstract:A direct and eco-friendly nitration methodology to synthesize 3-nitroquinoline N-oxides from quinoline N-oxides using tert-butyl nitrite as both the nitro source and oxidant has been developed. Although this reaction undergoes a free Radical Process, it exhibits high regioselectivity and can be smoothly scaled up to gram scale.
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merging the ring opening of benzoxazoles with secondary amines and an iron catalyzed oxidative cyclization towards the environmentally friendly synthesis of 2 aminobenzoxazoles
ChemInform, 2014Co-Authors: Wenfang Wang, Chengxia Miao, Qiaohong Zhang, Chungu Xia, Wei SunAbstract:A feasible Radical Process is proposed for the oxidative cyclization on the basis of mechanistic studies.
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Merging the ring opening of benzoxazoles with secondary amines and an iron-catalyzed oxidative cyclization towards the environmentally friendly synthesis of 2-aminobenzoxazoles
Green Chemistry, 2013Co-Authors: Wenfang Wang, Chengxia Miao, Qiaohong Zhang, Chungu Xia, Wei SunAbstract:A facile and environmentally friendly method was developed through merging the ring opening of benzoxazoles with secondary amines and an iron-catalyzed oxidative cyclization towards the synthesis of 2-aminobenzoxazoles. In the oxidative cyclization step, with catalytic amounts of FeCl and aqueous H2O2 as a green oxidant, highly desirable 2-aminobenzoxazoles were isolated in excellent yields of up to 97%. A plausible Radical Process is proposed for the oxidative cyclization on the basis of mechanistic studies.
Zhongquan Liu - One of the best experts on this subject based on the ideXlab platform.
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copper catalyzed decarboxylative alkenylation of sp3 c h bonds with cinnamic acids via a Radical Process
ChemInform, 2013Co-Authors: Zili Cui, Xiaojie Shang, Xiangfeng Shao, Zhongquan LiuAbstract:The coupling of aryl-substituted acrylic acids with alcohols, ethers, and hydrocarbons provides a useful method for the stereospecific synthesis of substituted (E)-alkenes (33 examples).
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copper and iron catalyzed decarboxylative tri and difluoromethylation of α β unsaturated carboxylic acids with cf3so2na and cf2hso2 2zn via a Radical Process
Organic Letters, 2013Co-Authors: Zili Cui, Zhongquan LiuAbstract:A copper-catalyzed decarboxylative trifluoromethylation of various α,β-unsaturated carboxylic acids by using a stable and inexpensive solid, sodium trifluoromethanesulfinate (CF3SO2Na, Langlois reagent), was developed. In addition, an iron-catalyzed difluoromethylation of aryl-substituted acrylic acids by using zinc difluoromethanesulfinate (DFMS, (CF2HSO2)2Zn, Baran reagent) via a similar Radical Process was also achieved.
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copper catalyzed decarboxylative alkenylation of sp3 c h bonds with cinnamic acids via a Radical Process
Chemical Science, 2012Co-Authors: Zili Cui, Xiaojie Shang, Xiangfeng Shao, Zhongquan LiuAbstract:A copper-catalyzed decarboxylative coupling of vinylic carboxylic acids with simple alcohols, ethers, and hydrocarbons was achieved. In the past decades, most of the sp3 α-C–H activation/C–C bond formation reactions proceeded via an addition of a α-hydroxy carbon-centered Radical to heterocycles, alkenes, and alkynes. The present system exhibits a novel pathway for the functionalization of various sp3 C–H bonds via Radical addition–elimination of aryl-substituted vinyl carboxylic acids. This strategy allows for rapid and selective access to a variety of (E)-alkenes such as allylic alcohols, allylic ethers, and substituted styrenes. In addition, this procedure could be scaled up to gram level, which would be useful to prepare natural products and pharmaceuticals that contain chromene and its derivatives.
Xiaobing Wan - One of the best experts on this subject based on the ideXlab platform.
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Interception of Radicals by Molecular Oxygen and Diazo Compounds: Direct Synthesis of Oxalate Esters Using Visible-Light Catalysis
Organic letters, 2018Co-Authors: Weiwei Hao, Yonggao Zheng, Pengcheng Lian, Xiaobing WanAbstract:The synthesis of oxalate esters through a Radical Process, rather than the traditional ionic reaction, has been well developed in which the Radicals induced by visible light are trapped by molecular oxygen and diazo compounds under room temperature. This reaction is operationally simple, mild, and shows broad substrate scopes in α-bromo ketones and diazo compounds.
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bu4ni catalyzed cross coupling between sulfonyl hydrazides and diazo compounds to construct β carbonyl sulfones using molecular oxygen
Organic Letters, 2016Co-Authors: Yaxiong Wang, Ying Shao, Hao Zheng, Xiaobing WanAbstract:A new cross-coupling reaction between sulfonyl hydrazides and diazo compounds has been established, leading to a variety of β-carbonyl sulfones in good yields. This methodology was distinguished by simple manipulation, easily available starting materials, and wide substrate scope. A plausible mechanism involving a Radical Process was proposed based upon the experimental observations and literature.
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cu based carbene involved in a Radical Process a new crossover reaction to construct γ peroxy esters and 1 4 dicarbonyl compounds
Chemical Communications, 2015Co-Authors: Jiewen Jiang, Jiajun Liu, Ling Yang, Ying Shao, Jiang Cheng, Xiaoguang Bao, Xiaobing WanAbstract:Through merging Cu-based carbenes in a Radical Process, a novel crossover reaction has been successfully established, leading to the facile and efficient syntheses of various γ-peroxy esters and 1,4-dicarbonyl compounds. Considering that both Cu-based carbene complexes and Radicals are extremely reactive, and therefore exist only in extraordinarily low concentrations, the high selectivity of this coupling reaction is unusual.
Guosheng Liu - One of the best experts on this subject based on the ideXlab platform.
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Enantioselective Copper-Catalyzed Intermolecular Amino- and Azidocyanation of Alkenes in a Radical Process
Angewandte Chemie (International ed. in English), 2017Co-Authors: Dinghai Wang, Fei Wang, Pinghong Chen, Zhenyang Lin, Guosheng LiuAbstract:Asymmetric copper-catalyzed intermolecular amino- and azidocyanation reactions of alkenes have been developed that proceed via a Radical Process in which a key benzylic Radical intermediate is enantioselectively trapped by a chiral Box/CuII cyanide complex. A variety of enantiomerically enriched β-amino/azido alkylnitriles were efficiently synthesized. The β-azido alkylnitriles could be converted into a series of highly valuable optically active amine-based building blocks and bioactive compounds.
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Enantioselective Copper-Catalyzed Intermolecular Cyanotrifluoromethylation of Alkenes via Radical Process.
Journal of the American Chemical Society, 2016Co-Authors: Fei Wang, Dinghai Wang, Xiaolong Wan, Pinhong Chen, Guosheng LiuAbstract:A novel enantioselective copper-catalyzed intermolecular cyanotrifluoromethylation of alkenes has been developed, in which a variety of CF3-containing alkylnitriles are furnished with excellent enantiomeric excess. Preliminary mechanistic studies revealed (1) the reaction was initiated by a SET Process between activated Togni’s CF3+ reagent and a Cu(I) catalyst; (2) the released CF3 Radical readily added to styrene to provide a benzylic Radical, which was then trapped by a chiral Cu(II) cyanide species to deliver the desired alkylnitriles; (3) a low concentration of the CN anion was crucial to obtain high enantioselectivity.
Kaida Zhou - One of the best experts on this subject based on the ideXlab platform.
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recent advances in the functionalization of allenes via Radical Process
Tetrahedron, 2018Co-Authors: Guanyinsheng Qiu, Jun Zhang, Kaida ZhouAbstract:Abstract This review is focused on the recent advances in the functionalization of allenes via Radical Process. Different Radical partners including carbon Radicals and heteroatom Radicals are discussed in the reactions of allenes. Generally, the Radical formed in situ would attack the allene at the central carbon leading to allyl Radical intermediate. However, the formation of alkenyl Radical intermediate from allene could be observed as well in some cases with high regioselectivity and stereoselectivity.
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recent advances in the sulfonylation of c h bonds with the insertion of sulfur dioxide
Chemical Communications, 2018Co-Authors: Guanyinsheng Qiu, Kaida ZhouAbstract:Recent advances in the sulfonylation of C-H bonds with the insertion of sulfur dioxide are summarized. Usually, a sulfur dioxide surrogate, DABCO·(SO2)2, is used, which avoids the utilization of gaseous sulfur dioxide in the transformation. Inorganic sulfites such as sodium metabisulfite are also effective in C(sp3)-H bond sulfonylation. C-H bond sulfonylation under transition metal catalysis or through a Radical Process has been developed. In some cases, the sulfonylation can be performed under catalyst- and additive-free conditions, or can be facilitated by visible light irradiation. The efficiency is also investigated by merging the Radical Process and metal catalysis.
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insertion of sulfur dioxide via a Radical Process an efficient route to sulfonyl compounds
Organic chemistry frontiers, 2018Co-Authors: Guanyinsheng Qiu, Kaida Zhou, Liang GaoAbstract:This review is focused on the recent advances in the chemistry of sulfur dioxide fixation through a Radical Process. Diverse sulfonyl compounds can be obtained efficiently under mild conditions. In general, aryl Radicals, vinyl Radicals, alkyl Radicals, and nitrogen-centered Radicals can react with sulfur dioxide, giving rise to sulfonyl Radical intermediates. The resulting sulfonyl Radicals can be captured by nucleophiles, olefins, and alkynes. The sources of aryl Radicals from aryldiazonium salts, aryl halides, and diaryliodonium salts are demonstrated. It is believed that more amazing SO2-based achievements will be developed in the near future.
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generation of benzosultams via a Radical Process with the insertion of sulfur dioxide
Organic chemistry frontiers, 2017Co-Authors: Kaida Zhou, Hongguang XiaAbstract:An efficient route to diverse 3-sulfonated-2,3-dihydrobenzo[d]isothiazole 1,1-dioxides is achieved through a three-component reaction of 2-ethynylbenzenesulfonamides, DABCO-bis(sulfur dioxide), and aryldiazonium tetrafluoroborates. The corresponding sulfonated benzosultams are produced in moderate to good yields. During the reaction Process, the in situ generated arylsulfonyl Radical via addition of an aryl Radical to sulfur dioxide and the subsequent single electron transfer would be the key steps for the final outcome. DABCO acts as the carrier for single electron transfer, as well as a base to promote the C–N bond formation.
