Radical alkynyltrifluoromethylation of alkenes with actylenic triflones has been achieved. This radical chain reaction is initiated by a catalytic amount of an electron-donor–acceptor complex composed of Togni’s reagent and N-methylmorpholine. This transformation proceeds under exceptionally mild and operationally simple conditions. A variety of alkenes are compatible in this protocol including aliphatic
A silver-initiated free-radical intermolecular hydrophosphinylation of unactivated alkenes
作者:Zejiang Li、Fenghua Fan、Zengyan Zhang、Yingxia Xiao、Dong Liu、Zhong-Quan Liu
DOI:10.1039/c5ra04136h
日期:——
A scalable, operationally easy intermolecular hydrophosphinylation of various unactivated alkenes with H–P(O) compoundsviaan Ag(i)-initiated free radical process was developed. Mechanistic studies suggest that atom transfer processes were involved in this system.
Silver-Catalyzed Trifluoromethylalkynylation of Unactivated Alkenes with Hypervalent Iodine Reagents
作者:Xinkan Yang、Gavin Chit Tsui
DOI:10.1021/acs.orglett.9b03230
日期:2019.11.1
unactivated alkenes is presented. The reaction is catalyzed by silver(I) trifluoroacetate for the simultaneous construction of two C-C bonds (alkyl-alkyne and alkyl-CF3). By employing versatile hypervalentiodinereagents, ethynylbenziodoxolones, useful trifluoromethylalkynylated compounds can be prepared from simple alkenes displaying excellent functional group tolerability. A radical mechanism is proposed
Radical Pentafluoroethylation of Unactivated Alkenes Using CuCF<sub>2</sub>CF<sub>3</sub>
作者:Xinkan Yang、Gavin Chit Tsui
DOI:10.1021/acs.orglett.0c01646
日期:2020.6.5
source for the CF2CF3 radical under aerobic conditions at room temperature. Using this system, readily available unactivatedalkenes can be pentafluoroethylated to provide novel allylic CF2CF3 compounds with excellent E-selectivity and functional group tolerability. Mechanistic studies including TEMPO–CF2CF3 trapping and radical clock experiments provided strong evidence for radical pathways, offering
The first copper and zinc copromoted trifluoromethylation using trifluoromethanesulfonic anhydride (Tf2O) as a trifluoromethylating reagent has been developed. The reaction of alkenes or alkynes with Tf2O in the presence of CuX2 (X = Br, Cl), Zn powder, and 2,2′-bipyridine affords bromo(chloro)trifluoromethylated products in good yields. CuX2 plays a dual role as the catalyst and halide source, whereas