Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
Chemistry. 2013 Mar 18;19(12):3932-42. doi: 10.1002/chem.201204491. Epub 2013 Feb 11.
A number of enol ether-derived diaurated species were synthesized directly from different alkynols and cationic gold complexes in the presence of a non-nucleophilic base (proton sponge). The reaction can be easily applied for in situ generation of diaurated species from all common types of hydroalkoxylation substrates: 5-endo, 5-exo/6-endo, 6-exo/7-endo and intermolecular types. Six examples were also synthesized in individual state as stable hexafluoroantimonate salts. Whereas diaurated species are obtained reliably from all conventional mononuclear gold catalysts, application of binuclear ones often gave diaurated species with unusual properties. The preliminary results point to complexities of behavior of binuclear gold catalysts and would require more research in future for this subclass. The formation of diaurated species from various gold-oxo compounds (LAu)2 OH(+) , (LAu)3 O(+) , and LAuOH (L=phosphine ligand) was also studied. Of these three types, only (LAu)2 OH(+) is reactive, whereas (LAu)3 O(+) and LAuOH are not reactive alone but require acidic promoters to enable the reaction. These differences in reactivity were explained by ability of these compounds to generate the necessary acetylene π-complex intermediate.
许多烯醚衍生的二芳基化物种直接由不同的炔醇和阳离子金配合物在非亲核碱（质子海绵）的存在下合成。该反应可轻松应用于从所有常见类型的氢烷氧基化底物原位生成二芳基化物种：5-endo、5-exo/6-endo、6-exo/7-endo 和分子间类型。还以六氟锑酸盐盐的稳定单体形式合成了六个实例。尽管二芳基化物种可从所有常规单核金催化剂可靠地获得，但双核催化剂的应用通常会得到具有不寻常性质的二芳基化物种。初步结果表明双核金催化剂的行为复杂，将来需要对此子类进行更多研究。还研究了各种金-氧（LAu）2 OH(+)、(LAu)3 O(+)和 LAuOH（L=膦配体）金-氧化合物形成二芳基化物种的情况。在这三种类型中，只有（LAu）2 OH(+)是反应性的，而（LAu）3 O(+)和 LAuOH 单独不反应，但需要酸性促进剂才能使反应发生。这些反应性差异可通过这些化合物生成必要的乙炔π-配合物中间体的能力来解释。
