aldehydes and α-trifluoromethyl alkenes, which provides novel and efficientaccess to diverse gem-difluorohomoallylic alcohols. Remarkably, the high chemoselectivity of this reaction enables the conversion of the formyl moiety in the presence of various easily reducible functionalities including ketone, organohalides, aziridine, sulfone, alkyne, and unactivated alkene. The utility of this method is demonstrated
Synthesis of <i>gem</i>-Difluoroalkenes via Nickel-Catalyzed Allylic Defluorinative Reductive Cross-Coupling
作者:Yun Lan、Feiyan Yang、Chuan Wang
DOI:10.1021/acscatal.8b02784
日期:2018.10.5
ted alkenes was achieved with easily accessible primary, secondary and tertiary alkyl halides as the coupling partners and Zn-powder as reducing agent. This process provides an efficient and convenient entry to gem-difluoroalkenes bearing various sensitive functional groups under mild reaction conditions. Moreover, this method proves to be suitable for late-stage functionalization of multifunctional
Photocatalytic hydroacylation of trifluoromethyl alkenes
作者:Pei Fan、Chang Zhang、Yun Lan、Zhiyang Lin、Linchuan Zhang、Chuan Wang
DOI:10.1039/c9cc07285c
日期:——
Hydrofunctionalization of trifluoromethyl alkenes is highly challenging, because the nucleophilic addition is oftentimes followed by β-F elimination in this case. By the use of tetrabutylammonium decatungstate (TBADT) as a hydrogen-atom-transfer (HAT) photocatalyst for acyl C–H activation, we successfully avoid the β-F elimination in the hydroacylation of trifluoromethyl alkenes with aldehydes. This light (390
Merger of C–F and C–N Bond Cleavage in Cross-Electrophile Coupling for the Synthesis of <i>gem</i>-Difluoroalkenes
作者:Youxiang Jin、Jiaoyang Wu、Zhiyang Lin、Yun Lan、Chuan Wang
DOI:10.1021/acs.orglett.0c01592
日期:2020.7.17
Herein we successfully applied Katritzky salts as the alkyl electrophile in the reductive allylic defluorinative cross-coupling reaction with α-trifluoromethyl alkenes. The merger of C–F and C–Nbondcleavage via the synergistic effect of nickel and zinc allows the efficient synthesis of diverse gem-difluoroalkenes with a good tolerance for various functional groups.
Photoredox Generation of Carbon-Centered Radicals Enables the Construction of 1,1-Difluoroalkene Carbonyl Mimics
作者:Simon B. Lang、Rebecca J. Wiles、Christopher B. Kelly、Gary A. Molander
DOI:10.1002/anie.201709487
日期:2017.11.20
facile, scalable route to access functional‐group‐rich gem‐difluoroalkenes. Using visible‐light‐activated catalysts in conjunction with an arsenal of carbon‐radical precursors, an array of trifluoromethyl‐substituted alkenes undergoes radical defluorinative alkylation. Nonstabilized primary, secondary, and tertiary radicals can be used to install functional groups in a convergent manner, which would otherwise