Centrum für Molekulare Materialien, Fakultät für Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany.
Chemistry. 2021 Apr 12;27(21):6465-6478. doi: 10.1002/chem.202005123. Epub 2021 Feb 8.
In this work, the syntheses of non-coordinated electron-rich phenolate anions via deprotonation of the corresponding alcohols with an extremely powerful perethyl tetraphosphazene base (Schwesinger base) are reported. The application of uncharged phosphazenes renders the selective preparation of anionic phenol-phenolate and phenolate hydrates possible, which allows for the investigation of hydrogen bonding in these species. Hydrogen bonding brings about decreased redox potentials relative to the corresponding non-coordinated phenolate anions. The latter show redox potentials of up to -0.72(1) V vs. SCE, which is comparable to that of zinc metal, thus qualifying their application as organic zinc mimics. We utilized phenolates as reducing agents for the generation of radical anions in addition to the corresponding phenoxyl radicals. A tetracyanoethylene radical anion salt was synthesized and fully characterized as a representative example. We also present the activation of sulfur hexafluoride (SF ) with phenolates in a SET reaction, in which the nature of the respective phenolate determines whether simple fluorides or pentafluorosulfanide ([SF ] ) salts are formed.
在这项工作中，通过使用极其强大的全乙基四磷杂环戊二烯基（Schwesinger 碱）将相应醇的去质子化来合成非配位富电子酚盐阴离子。未带电的磷氮杂环戊二烯的应用使得阴离子酚-酚盐和酚盐水合物的选择性制备成为可能，从而可以研究这些物种中的氢键。氢键导致相对于相应的非配位酚盐阴离子的还原电势降低。后者的还原电势高达-0.72(1) V 与 SCE 相比，这与锌金属相当，因此有资格将其用作有机锌模拟物。我们除了相应的苯氧基自由基外，还利用酚盐作为生成自由基阴离子的还原剂。合成了一种四氰乙烯自由基阴离子盐，并作为代表性实例进行了充分表征。我们还展示了酚盐与六氟化硫（SF ）在 SET 反应中的活化作用，其中各自酚盐的性质决定了是形成简单的氟化物还是五氟化硫化物([SF ] )盐。
