No neutral silicon Lewis super acids are known to date. We report on the synthesis of bis(perchlorocatecholato)silane and verify its Lewis super acidity by computation (DLPNO-CCSD(T)) and experiment (fluoride abstraction from SbF ). The exceptional affinity towards donors is further demonstrated by, for example, the characterization of an unprecedented SiO F dianion and applied in the first hydrodefluorination reaction catalyzed by a neutral silicon Lewis acid. Given the strength and convenient access to this new Lewis acid, versatile applications might be foreseen.

The Lewis acidity of bis(catecholato)silanes is scaled and rationalized. Perbromination of the catechols provides the strongest silicon Lewis superacid.

Bisher sind noch keine neutralen Silicium-Lewis-Supersäuren bekannt. Wirberichtenhier über die Synthese des Bis(perchlorocatecholato)silans und bestätigen dessen Lewis-Superaziditätd urchB erechnungen (DLPNO-CCSD(T)) und Experimente (Fluoridabstraktion von SbF 6 À