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Cu(OH)2 supported on Fe(OH)3 as a synergistic and highly efficient system for the dehydrogenation of ammonia-borane

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Science Bulletin 2018年第23期63卷 1583-1590页

作者： Cheng-Yun Peng Chun-Chao Hou Qian-Qian Chen Chuan-Jun Wang Xiao-Jun Lv Jun Zhong Wen-Fu Fu Chi-Ming Che Yong Chen Key Laboratory of Photochemical Conversion and Optoelectronic Materials & HKU-CAS Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijmg 100190China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Material Science Shandong Agricultural UniversityTaian 271018China Institute of Functional Nano and Soft Materials Laboratory (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow University Suzhou 215123China State Key Laboratory of Synthetic Chemistry and Department of Chemistry The University of Hong KongHongKongChina

Herein,we first describe the physical mixture of Cu(OH)_2/Fe(OH)_3 as a composite catalyst precursor for the dehydrogenation of ammonia borane(AB)in methanol.During the initial period of catalytic reaction,Cu nanoparticles were formed in-situ.The catalytic activity of Cu nanoparticles can be significantly enhanced with the assistance of Fe species and OH~à.A maximum turnover frequency(TOF)of 50.3 mol_(H2)mol^(à1)_(total metal)min^(à1)(135.6 mol_(H2)mol_(Cu)^(à1)min^(à1))was achieved at ambient temperature,which is superior to those of previously reported Fe or Cu based systems.

关键词： Ammonia borane Dehydrogenation Cu(OH)2 Fe(OH)3

Asymmetric Reduction of Acetophenone O-Methyloxime with Reagents Prepared from L-Proline and borane

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Chinese Journal of Chemistry 2003年第8期21卷 1108-1110页

作者：杜平陈贞亮王琳刘晖陈代谟 Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences

Asymmetric reduction of acetophenone O methyloxime with reagents in situ prepared from L proline and borane has been investigated. A series of conditions optimization were made, including an examination of the effect of the temperature of catalyst pretreatment, the temperature of reduction, the amount of borane, the additive, the solvent, the reducing agent and various chiral auxiliaries on the enantioselectivity. Under the optimal condition, ( S ) α phenylethylamine was obtained in 53% yield with 83 1% ee in the presence of 25 mol% L proline.

关键词： asymmetric reduction chiral auxiliary L proline borane acetophenone O methyloxime

Chemoselective Dual Functionalization of Phenols via Relay Catalysis of borane with Different Forms

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CCS Chemistry 2021年第8期3卷 2248-2261页

作者： Xiaowen Tang Xiang Luo Qiong Su Gaofei Wei Shan-Shui Meng Albert S.C.Chan School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006 School of Pharmacy Qingdao UniversityQingdao 266021 Institute of Medical Research Northwestern Polytechnical UniversityXi’an 710072

A highly efficient and chemoselective dual functionalization of unprotected phenols withα-orβ-hydroxyl acids is presented.A variety of valuable benzofuranones and dihydrocoumarins are delivered in moderate to high yields.Density functional theory(DFT)calculations and control experiments indicate that an untypical Friedel–Crafts alkylation and the subsequent lactonization are catalyzed by the Lewis acid form and the Brønsted acid form of borane,respectively.Gram-scale experiments and late-stage functionalization of complex molecules have been performed to highlight the utility of this reaction.

关键词： relay catalysis Friedel–Crafts alkylation unprotected phenols borane ortho-selectivity

Boron-promoted reductive deoxygenation coupling reaction of sulfonyl chlorides for the C(sp3)-S bond construction

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Chinese Chemical Letters 2022年第12期33卷 5101-5105页

作者： Shuo Chen Qingru Wen Yanqing Zhu Yanru Ji Yu Pu Zhengli Liu Yun He Zhang Feng Chongqing Key Laboratory of Natural Product Synthesis and Drug Research School of Pharmaceutical SciencesChongqing UniversityChongqing 401331China Medical Imaging Key Laboratory of Sichuan Province North Sichuan Medical CollegeNanchong 637000China

Herein,we report a borane-promoted reductive deoxygenation coupling reaction to synthesize sulfides.This reaction features excellent functional group compatibility,high efficiency,broad substrate scope,and application in late-stage functionalization of biomolecules.Preliminary mechanistic studies suggest diaryl sulfides are the intermediates of this reaction.Moreover,the real active aryl sulfide anions may be generated in situ with the aid of B2pin2 and react with alkyl tosylates through a concerted SN2 pathway.

关键词： C-S bond formation Reductive deoxygenation coupling borane Organosulfur compounds Green chemistry

EFFECTS　OF　RATE　OF　ADDITION　AND　TENIPERATURE　ON　THE　ENANTIOSELECTIVITY　IN　borane　REDUCTION　OF　KETONES　CATALYZED　BY　CHIRAL　OXAZABOROLIDINE

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Chinese Chemical Letters 1995年第1期6卷 9-12页

作者： Yao Zhong JIANG Yong QIN snd Ai Qiao MIChengdu Institute of Organic Chemtetry, A cademia Sinica, Chengdu 610041

The exoellent enantioselectivity with o. p. >99% in asymmetrio borane reduction of acetophenone catalyzed by (4S, 5R ) 4, 5-diphenyi-1. 3. 2-oxazaborolidine has been achieved via the important modincation of the rea... 详细信息

关键词： RATE REDUCTION borane BY CATALYZED CHIRAL EFFECTS IN KETONES OF

Activation and Deactivation of Chain-transfer Agent in Controlled Radical Polymerization by Oxygen Initiation and Regulation

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Chinese Journal of Polymer Science 2020年第11期38卷 1178-1184,I0006页

作者： Chun-Na Lv Ning Li Yu-Xuan Du Jia-Hua Li Xiang-Cheng Pan State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China

The activation and deactivation of the chain-transfer agent were achieved by oxygen initiation and regulation with triethylborane under ambient temperature and atmosphere.The autoxidation of triethylborane overcame the oxygen inhilbition and produced initiating radicals that selectively activate the chain-transfer agent for the chain growth or deactivate the active chain-end of polymer in controlled radical polymerization.Both activation and deactivation were highly efficient with broad scope for various polymers with different chain-transfer agents in both organic and aqueous systems.Oxygen molecule was particularly used as an external regulator to initiate and achieve the temporal control of both activation and deactivation by simply feeding the air.

关键词： RAFT Oxygen borane

Dehydrocoupling of boranes with amines using a scandium catalyst

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Chinese Chemical Letters 2021年第12期32卷 4002-4005页

作者： Yang Wang Pengfei Xu Xin Xu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

The scandocene alkyl complex(C_(5)Me_(5))_(2)ScCH_(2)SiMe_(3)was found to be an efficient catalyst for the dehydrocoupling of the non-cyclic boranes, dicyclohexylborane and thexylborane, with amines under mild conditions. The reactions afforded the corresponding aminoboranes in high yields with good functional group tolerance. The stoichiometric reaction of scandium alkyl with amine led to the isolation of a scandium amide complex, which was shown to be an active species during the catalysis. Although a boranecoordinated scandium hydride was also obtained from the stoichiometric experiment, it was not involved in the catalytic cycle. In addition, kinetic studies provided insight into this intermolecular dehydrogenation reaction.

关键词： borane Aminoborane Dehydrocoupling Scandium β-H elimination

Zwitterionic Hydroboranes Stabilized by β-Diimine Framework

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Chinese Journal of Chemistry 2017年第6期35卷 886-888页

作者： Jianfeng Li Hongfan Hu Chunming Cui State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

Reaction of the N-heterocyclic borane [MeCCHC（CHe）（NAr）2]Btt （1, Ar=2,6-Me2C6H3） with B（C6F5）3 af- forded the zwitterionic hydroborane [MeCCHC（CHz）B（C6F5）3（NAr）2]BH, in which the β-methyl group can be d... 详细信息

关键词： borane cation zwitterion diimine deprotonation

ASYMMETRIC　SYNTHESIS　ⅩⅩⅧ:　ENANTIOSELECTIVE　REDUCTION　OF　AROMATIC　KETONES　CATALYZED　BY　NEW　CHIRAL　CATALYST-(4R,8R,9S)-CAMPHANE[8,9-b]-1,3,2-OXATHIOBOROLIDINE

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Chinese Chemical Letters 1996年第5期7卷 415-418页

作者： Yao Zhong Jiang Xiao Ming Feng Liu Zhu Gong Zhi Li Gut Su Yang Ai Qiao Mi (Union Laboratory of Asymmetric Synthesis,Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences. Chengdu 610041.) Union Lab. of Asymmetric Synthesis Chengdu Inst. of Organic Chemistry Chinese Academy of Sciences Chengdu 610041

Abstract: (4R, 8R,9S)-Camphane[8, 9-b]-1,3,2-oxathioborolidine prepared from (1R,2S.3R)-3-mercapto-camphol with borane was used as catalyst in the enantioselective reduction of aromatic ketones: moderate enantioselectivities with e.e. 7.44%-51 04%have been obtained for aromatic ketones with 20% mol catalyst, 73 .78% e.e for ω-bromo acetophenone with 100% mol catalyst.

关键词： borane