α,α-Difluoro-α-phenylsulfanylmethyl carbanion equivalent: a novel gem-difluoromethylenation of carbonyl compounds
摘要:
alpha,alpha-Difluoro-alpha-phenylsulfanyl-alpha-trimethylsilylmethane (PhSCF2SiMe3) has been demonstrated as an alpha,alpha-difluoro-alpha-plhenylsulfanylmethyl carbanion equivalent. gem-Difluorophenylsulfanylmethylation of carbonyl compounds has been successfully achieved by using PhSCF2SiMe3 in the presence of TBAF in THE The adducts have been converted to the corresponding gem-difluoroalkenes by a novel pyrolytic and/or FVP elimination of the beta-hydroxy-alpha-phenyisufinyl derivatives under reduced pressure. (c) 2006 Elsevier Ltd. All rights reserved.
Deoxygenative <i>gem</i>-difluoroolefination of carbonyl compounds with (chlorodifluoromethyl)trimethylsilane and triphenylphosphine
作者:Fei Wang、Lingchun Li、Chuanfa Ni、Jinbo Hu
DOI:10.3762/bjoc.10.32
日期:——
phosphonium ylide represents one of the most straightforward methods. RESULTS: The combination of (chlorodifluoromethyl)trimethylsilane (TMSCF2Cl) and triphenylphosphine (PPh3) can be used for the synthesis of gem-difluoroolefins from carbonyl compounds. Comparative experiments demonstrate that TMSCF2Cl is superior to (bromodifluoromethyl)trimethylsilane (TMSCF2Br) and (trifluoromethyl)trimethylsilane
Visible-light-promoted<i>E</i>-selective synthesis of α-fluoro-β-arylalkenyl sulfides<i>via</i>the deoxygenation/isomerization process
作者:Yuxiu Li、Xiangqian Li、Xiaowei Li、Dayong Shi
DOI:10.1039/d0cc08254f
日期:——
Regioselective synthesis of α-fluoro-β-arylalkenyl sulfides has been established with gem-difluoroalkenes and sodium sulfinates in a transition-metal-free manner. A series of control experiments were executed to demonstrate thiol radicals and anions as the proposed intermediates. Notably, regioselective Z → E isomerization was achieved under green light irradiation in the absence of a photoinitiator
Highly <i>E</i>-Selective Synthesis of α-Fluoro-β-arylalkenyl Sulfones from <i>gem</i>-Difluoroalkenes with Sodium Sulfinates
作者:Yuxiu Li、Xiangqian Li、Xiaowei Li、Dayong Shi
DOI:10.1021/acs.joc.1c00490
日期:2021.5.7
The straightforward synthesis of α-fluoro-β-arylalkenyl sulfones under transition-metal- and base-free conditions has been described, which displays broad functional group compatibility and high stereoselectivity. In particular, the strategy is also applied to the late-stage modification of complex natural products and drugs.
described. This novel catalytic transformation proceeds in the presence of Pd(acac)2/1,2‐bis((di‐tert‐butylphosphan‐yl)methyl)benzene (btbpx) (L4) and allows for an efficient and straightforward access to a range of difluoromethylated esters in high yields and regioselectivities. The synthetic utility of the protocol is showcased in the practical synthesis of a Cyclandelate analogue using this methodology
which otherwise are essentially reluctant towards F‐nucleoplilic addition, now readily participate in this fluoroallylation reaction. Furthermore, this strategy provides an elegant example for the generation, as well as functionalization, of α‐CF3‐substituted benzylic radical intermediates using cheap and readily available starting materials.