Chlorodifluoromethyl phenyl sulfone, a previously unknown compound that can be readily prepared from non-ODS-based precursors, was found to act as a robust difluorocarbene reagent for O- and N-difluoromethylations.
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
<i>N</i>-Difluoromethylation of Imidazoles and Benzimidazoles Using the Ruppert–Prakash Reagent under Neutral Conditions
作者:G. K. Surya Prakash、Sankarganesh Krishnamoorthy、Somesh K. Ganesh、Aditya Kulkarni、Ralf Haiges、George A. Olah
DOI:10.1021/ol403007j
日期:2014.1.3
using TMS-CF3 (the Ruppert–Prakash reagent) underneutralconditions. Difluoromethylated products were obtained in good-to-excellent yields. Inexpensive, commercially available starting materials, neutralconditions, and shorter reaction times are advantages of this methodology. Reactions are accessible through conventional as well as microwave irradiation conditions.
Difluoromethylation of the activated X–H bond and aliphatic thiols, and gem-difluorocyclopropenation of alkynes with difluorocarbene generated by decarboxylation are described.