2-(Pyridinium-1-yl)-1,1-bis(perfluoroalkylsulfonyl)ethan-1-ide: A Practical Reagent for Synthesis of Strongly Acidic 1,1-Bis(perfluoroalkylsulfonyl)alkanes
作者:Hikaru Yanai、Ryuta Takahashi、Yoichi Takahashi、Akira Kotani、Hideki Hakamata、Takashi Matsumoto
DOI:10.1002/chem.201700515
日期:2017.6.16
By mixing (RfSO2)2CH2 (Rf = perfluoroalkyl), paraformaldehyde, and substituted pyridines, a three-component reaction proceeded smoothly to give unusual zwitterions bearing both pyridinium and stabilized carbanion moieties in good to excellent yields. Of these, 2-fluoropyridinium derivatives rapidly dissociated in acetonitrile to give equilibrium mixtures of the zwitterions and (RfSO2)2C=CH2/2-fluoropyridine
通过混合(RfSO2)2CH2(Rf =全氟烷基),多聚甲醛和取代的吡啶,三组分反应可顺利进行,从而得到具有吡啶鎓和稳定化碳负离子基团的不寻常的两性离子,收率高至优异。其中,2-氟吡啶鎓衍生物在乙腈中迅速解离,得到两性离子和(RfSO2)2C = CH2 / 2-氟吡啶的平衡混合物,这已通过详细的温度可变NMR研究得到证实。这种2-氟吡啶鎓的动力学行为促使我们研究它们作为贮存稳定,易于处理的(RfSO2)2C = CH2源的效用。用这些试剂,我们成功地合成了强酸性碳酸(RfSO2)2CHR,它是一种新型的酸催化剂。而且,