作者:Lanny S. Liebeskind、Marvin S. Yu、Richard H. Yu、Jianying Wang、Karl S. Hagen
DOI:10.1021/ja00073a021
日期:1993.10
oxidative dimerization of (tri-n-butylstannyl)cyclobutene-1,2-diones (providing symmetrically substituted bisquaryls) or by a palladium-copper cocatalyzed cross-coupling of 3-substituted-4-(tri-n-butylstannyl)-3-cyclobutene-1,2-diones with 3-halo-4-substituted-3-cyclobutene-1,2-diones (providing a route to unsymmetrically substituted bisquaryls). The novel parent bisquaric acid is a very strong BrOnsted acid
4,4'-Bi(cyclobutene-1,2-diones),一种衍生自方酸的新型化合物,此处命名为双方芳基,首次通过钯催化的(三正丁基甲锡烷基)环丁烯氧化二聚反应制备-1,2-二酮(提供对称取代的双四芳基)或通过钯-铜共催化的 3-取代-4-(三正丁基甲锡烷基)-3-环丁烯-1,2-二酮与 3-卤素的交叉偶联-4-取代-3-环丁烯-1,2-二酮(提供不对称取代双四芳基的途径)。新的母体双方酸是一种非常强的布朗斯台德酸,显然在溶解时完全电离;仅观察到一个 pK a 值 (pK a = -4.49)