<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
Copper-Mediated Deuterotrifluoromethylation of <i>α</i>
?Diazo Esters
作者:Mingyou Hu、Qiqiang Xie、Xinjin Li、Chuanfa Ni、Jinbo Hu
DOI:10.1002/cjoc.201600004
日期:2016.5
ation of α?diazo esters under the promotion of deuterium oxide (D2O) has been developed for the synthesis of deuterium‐labeled trifluoromethyl compounds. This deuterotrifluoromethylation reaction is of broad scope and can afford the deuterated products with higher than 99% isotopic purity. Moreover, the results of this investigation also provide some experimental evidences to support our previously
Stereoselective Synthesis of Difluorinated 1,3-Dienes via Palladium-Catalyzed C–F Bond Activation of Tetrasubstituted <i>gem</i>-Difluoroalkenes
作者:Yanhui Wang、Qiao Ma、Gavin Chit Tsui
DOI:10.1021/acs.orglett.1c01768
日期:2021.7.2
Pd(0)-catalyzed synthesis of difluorinated 1,3-dienes is described. Symmetrical 1,3-dienes containing a vicinal difluoro moiety can be obtained as single diastereomers from tetrasubstituted gem-difluoroalkenes. The reaction presumably proceeds through a stereoselective twofold Pd-catalyzed Miyaura borylation/Suzuki–Miyaura cross-coupling of the C–F bond. Moreover, modular synthesis of unsymmetrical
Highly Selective C–F Bond Functionalization of Tetrasubstituted <i>gem</i>-Difluoroalkenes and Trisubstituted Monofluoroalkenes Using Grignard Reagents
metal catalyst. β,β-Difluoroacrylates react with Grignard reagents under mild conditions to afford tetrasubstituted (E)-β-monofluoroacrylates. Experimental and computational studies revealed that the selectivity stems from the intrinsic reactivitydifference between the (E)- and (Z)-isomers toward excess Grignard reagent, which leads to the resolution of the two products.
我们在此描述了在没有过渡金属催化剂的情况下使用格氏试剂对四取代偕二氟烯烃和三取代单氟烯烃进行选择性 C-F 键官能化。β,β-二氟丙烯酸酯与格氏试剂在温和条件下反应生成四取代 ( E )-β-单氟丙烯酸酯。实验和计算研究表明,选择性源于 ( E )- 和 ( Z )-异构体对过量格氏试剂的内在反应性差异,这导致两种产物的分离。
Palladium-Catalyzed Stereoselective Defluorosilylation of <i>gem</i>-Difluoroalkenes for the Synthesis of Tetrasubstituted Monofluorinated Vinylsilanes
作者:Yuwei Zong、Ziwei Luo、Gavin Chit Tsui
DOI:10.1021/acs.orglett.3c00718
日期:——
Stereoselectivesynthesis of tetrasubstituted vinylsilanes is a challenging task. We herein report a novel palladium(0)-catalyzed defluorosilylation of β,β-difluoroacrylates to access tetrasubstituted vinylsilanes containing the monofluoroalkene motif in excellent diastereoselectivities (>99:1). This is our first example of C–heteroatom bond formation from the C–F bond under such a Pd catalytic manifold