Asymmetric Double Activation Catalysis by Multicatalyst System

This chapter deals with asymmetric double activation catalysis realized reactions, with one of the reaction partners (or one functionality of a multifunctional substrate for an intramolecular reaction) being simultaneously activated by two or more distinct catalysts. To date, several efficient types of double activation catalysis have been reported, based on the authors' proposals, including (1) amino catalysis and Lewis base catalysis, (2) iminium and Brønsted acid catalysis, (3) Lewis acid and Brønsted base catalysis, (4) H-bond donor and Lewis base catalysis, and miscellaneous models. For better understanding of double activation catalysis, the chapter focuses on representative types of double activation catalysis and their application, and introduces control experiments if possible. The merging of H-bond donors with Lewis bases is an alternative strategy to develop multicatalyst systems.