<i>gem-</i>Difluoroolefination of Diazo Compounds with TMSCF<sub>3</sub> or TMSCF<sub>2</sub>Br: Transition-Metal-Free Cross-Coupling of Two Carbene Precursors
作者:Mingyou Hu、Chuanfa Ni、Lingchun Li、Yongxin Han、Jinbo Hu
DOI:10.1021/jacs.5b09888
日期:2015.11.18
fragment resulting from a diazocompound 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 diazocompounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cu-catalyzed gem-difluoroolefination of diazocompounds with TMSCF3, which possesses
Preparation of (2,2-difluoroethenylidene)bis(tributylstannane) and arylation reaction: efficient approach to 1,1-diaryl-2,2-difluoroethenes
作者:Seung Yeon Han、Hyo Young Lee、Jong Hee Jeon、In Howa Jeong
DOI:10.1016/j.tetlet.2012.01.127
日期:2012.4
Reaction of 2,2-difluoro-1-tributylstannylethenyl p-toluenesulfonate (1) with bis(tributyltin) in the presence of 5 mol % Pd(PPh3)4 and 30 equiv LiBr in THF at reflux temperature for 7 h afforded (2,2-difluoroethenylidene)bis(tributylstannane) (2) in a 70% yield. Coupling reaction of 2 with aryl iodides in the presence of 5 mol % Pd(PPh3)4 and 5 mol % CuI in DMF at 80 °C for 3–4 h provided the coupled
Synthesis of α-CF<sub>3</sub> and α-CF<sub>2</sub>H amines <i>via</i> the aminofluorination of fluorinated alkenes
作者:Ling Yang、Wen-Xin Fan、E. Lin、Dong-Hang Tan、Qingjiang Li、Honggen Wang
DOI:10.1039/c8cc03364a
日期:——
A novel synthesis of α-CF3 and α-CF2H amines via the aminofluorination of gem-difluoroalkenes and mono-fluoroalkenes, respectively, is reported. The method employsSelectfluor as an electrophilic fluorine source and acetonitrile as a nitrogen source. Mechanistic studies revealed a single-electron oxidation/fluorine-abstraction/Ritter-type amination pathway. The protocol allowed the synthesis of a broad
Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical–Radical Cross‐Coupling
作者:Qiang Wang、Yi Qu、Hao Tian、Yuxiu Liu、Hongjian Song、Qingmin Wang
DOI:10.1002/chem.201901349
日期:——
The first visible‐light‐induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical–radicalcross‐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
Stereoselective synthesis of α-fluoroacrylonitriles <i>via</i> organocatalytic cyanation of <i>gem</i>-difluoroalkenes and TMSCN
作者:Yu-Chuan Ma、Yang Zhang、Cheng-Zhi Gu、Guang-Fen Du、Lin He
DOI:10.1039/c9nj02370d
日期:——
An organocatalytic cyanationreaction of gem-difluoroalkenes was developed. Under the catalysis of 10 mol% DBU, gem-difluoroalkenes undergo a nucleophilic addition-β-elimination reaction with trimethylsilylcyanide to provide α-fluoroacrylonitriles in 50–98% yields with excellent Z/E selectivity.