1143-92-6Relevant academic research and scientific papers
Copper-Mediated Cross-Coupling of Diazo Compounds with Sulfinates
Wang, Qian,Liu, An,Wang, Yan,Ni, Chuanfa,Hu, Jinbo
supporting information, p. 6919 - 6924 (2021/09/11)
A copper-mediated cross-coupling reaction between a diazo compound and a sodium alkane(arene)sulfinate gives a sulfone as the product. This reaction proceeds under mild conditions and features excellent functional group compatibility. A wide range of sodium alkane(arene)sulfinates were successfully applied in this chemistry. Mechanistic studies revealed that the overall reaction efficiency of the sulfinates was in line with their nucleophilicity in this reaction.
Dehalogenative Cross-Coupling of gem-Difluoroalkenes with Alkyl Halides via a Silyl Radical-Mediated Process
Tian, Hao,Yang, Shaoxiang,Wang, Xiaochen,Xu, Wentao,Liu, Yuxiu,Li, Yongqiang,Wang, Qingmin
supporting information, p. 12772 - 12782 (2021/09/13)
Herein, we describe a convenient general protocol for monofluoroalkenylation reactions of alkyl bromides involving cooperative visible-light photoredox catalysis and halogen abstraction. Mechanistic experiments showed that the products were generated by selective cross-coupling of aliphatic radicals with fluoroalkenyl radicals. Silyl radical-mediated halogen abstraction enabled the protocol to be used for the monofluoroalkenylation of a broad range of alkyl and heteroaryl halides. The protocol could be carried out on a gram scale and was applied to cholesterol, indicating its utility for late-stage monofluoroalkenylation reactions.
Direct α-Monofluoroalkenylation of Heteroatomic Alkanes via a Combination of Photoredox Catalysis and Hydrogen-Atom-Transfer Catalysis
Tian, Hao,Xia, Qing,Wang, Qiang,Dong, Jianyang,Liu, Yuxiu,Wang, Qingmin
supporting information, p. 4585 - 4589 (2019/06/17)
In this study, a new C(sp3)-H monofluoroalkenylation reaction involving cooperative visible-light photoredox catalysis and hydrogen-atom-transfer catalysis to afford products generated by selective hydrogen abstraction and radical-radical cross-coupling was described. This mild, efficient reaction shows high regioselectivity for the α-carbon atoms of amines, ethers, and thioethers and thus allows the preparation of monofluoroalkenes bearing various substituents. The reaction was applied to two bioactive molecules, indicating its utility for late-stage monofluoroalkenylation of compounds with inert C(sp3)-H bonds.
Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical–Radical Cross-Coupling
Wang, Qiang,Qu, Yi,Tian, Hao,Liu, Yuxiu,Song, Hongjian,Wang, Qingmin
supporting information, p. 8686 - 8690 (2019/06/17)
The first visible-light-induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical–radical cross-coupling step was achieved. This method provided a mild, step-economical and redox-neutral route to privileged two different fluorinated difunctionalized allyl compounds. The utility of this method is illustrated by late-stage modification of medically important molecules.
Visible light photocatalytic decarboxylative monofluoroalkenylation of α-amino acids with: Gem -difluoroalkenes
Li, Jingjing,Lefebvre, Quentin,Yang, Haijun,Zhao, Yufen,Fu, Hua
supporting information, p. 10299 - 10302 (2017/09/25)
α-Amino acids are among the most common biologically active molecules in nature, and their functionalization has attracted much attention. In this communication, a novel, efficient and general visible-light photocatalytic decarboxylative monofluoroalkenylation of N-protected α-amino acids with gem-difluoroalkenes is reported, affording the corresponding α-amino monofluoroalkenes which might find applications in medical chemistry and materials science. The reaction proceeded at room temperature with high efficiency and tolerance of various functional groups.
Continuous Flow Synthesis and Purification of Aryldiazomethanes through Hydrazone Fragmentation
Lévesque, éric,Laporte, Simon T.,Charette, André B.
, p. 837 - 841 (2017/01/14)
Electron-rich diazo compounds, such as aryldiazomethanes, are powerful reagents for the synthesis of complex structures, but the risks associated with their toxicity and instability often limit their use. Flow chemistry techniques make these issues avoidable, as the hazardous intermediate can be used as it is produced, avoiding accumulation and handling. Unfortunately, the produced stream is often contaminated with other reagents and by-products, making it incompatible with many applications, especially in catalysis. Herein is reported a metal-free continuous flow method for the production of aryldiazomethane solutions in a non-coordinating solvent from easily prepared, bench-stable sulfonylhydrazones. All by-products are removed by an in-line aqueous wash, leaving a clean, base-free diazo stream. Three successful sensitive metal-catalyzed transformations demonstrated the value of the method.
gem-Difluoroolefination of Diazo Compounds with TMSCF3 or TMSCF2Br: Transition-Metal-Free Cross-Coupling of Two Carbene Precursors
Hu, Mingyou,Ni, Chuanfa,Li, Lingchun,Han, Yongxin,Hu, Jinbo
supporting information, p. 14496 - 14501 (2015/11/27)
A new olefination protocol for transition-metal-free cross-coupling of two carbene fragments arising from two different sources, namely, a nonfluorinated carbene fragment resulting from a diazo compound and a difluorocarbene fragment derived from Ruppert-Prakash reagent (TMSCF3) or TMSCF2Br, has been developed. This gem-difluoroolefination proceeds through the direct nucleophilic addition of diazo compounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cu-catalyzed gem-difluoroolefination of diazo compounds with TMSCF3, which possesses a narrow substrate scope due to a demanding requirement on the reactivity of diazo compounds and in-situ-generated CuCF3, this transition-metal-free protocol affords a general and efficient approach to various disubstituted 1,1-difluoroalkenes, including difluoroacrylates, diaryldifluoroolefins, as well as arylalkyldifluoroolefins. In view of the ready availability of diazo compounds and difluorocarbene reagents and versatile transformations of 1,1-difluoroalkenes, this new gem-difluoroolefination method is expected to find wide applications in organic synthesis.
Cu(I)-catalyzed coupling of diaryldiazomethanes with terminal alkynes: An efficient synthesis of tri-aryl-substituted allenes
Wu, Chenggui,Hu, Fangdong,Liu, Zhenxing,Deng, Guisheng,Ye, Fei,Zhang, Yan,Wang, Jianbo
, p. 9196 - 9201 (2015/11/27)
A highly efficient method for the synthesis of tri-aryl-substituted allenes has been developed through Cu(I)-catalyzed coupling of diaryldiazomethanes with terminal alkynes. The reaction is under mild conditions and uses simple and inexpensive CuI as the catalyst. Mechanistically, the reaction follows a pathway involving Cu(I) carbene migratory insertion.
Substituted diaryldiazomethanes and diazofluorenes: Structure, reactivity and stability
Davis, Philip J.,Harris, Lawrence,Karim, Aman,Thompson, Amber L.,Gilpin, Martin,Moloney, Mark G.,Pound, Matthew J.,Thompson, Claire
supporting information; experimental part, p. 1553 - 1556 (2011/04/26)
The synthesis of several substituted diaryldiazomethanes and diazofluorenes, and an assessment of their structure, reactivity and stability, is reported.
