Synthesis, characterization and electrochemical lithium-ion storage properties of sulfonylcalix[4]quinone†
Abstract
Based on the mature synthesis and de-tert-butylation of p-tert-butylthiacalix[4]arene, sulfonylcalix[4]quinone (SC4Q) bearing four sulfonyl-bridged groups was designed and synthesized for the first time. The whole synthetic strategy can be divided into four sections: selective oxidation of thiacalix[4]arene, diazo coupling of sulfonylcalix[4]arene precursors, amination of upper rim azo groups and oxidation of 5,11,17,23-tetraaminosulfonylcalix[4]arene. Nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis were applied to characterize its structural components. The structural optimization and conformational equilibration of SC4Q were performed by density functional theory calculation. Moreover, the presence of 1,4-benzoquinone units confers on the SC4Q molecule considerable potential as a cathode in rechargeable lithium-ion batteries and realizes electrochemically stable performance.