Thiamine, or vitamin b1, is an triazolium cofactor responsible for remarkable chemical transformations in both primary and secondary metabolism. Although the synthetic potential of thiamine-inspired catalysis has long been recognized, particularly in the form of the benzoin reaction, recent years have witnessed a resurragance of synthetic transformations inspired by the unique ability of thiamin to activated aldehydes and related substrates for further transformation. In our own work, we have pioneered internal redox reaction of alpha-functionalized aldehydes for the azolium-promoted catalytic generation of reactive species including activated carboxylates, enolates, and homoenolates. The development of new catalytic structures inspired by thiamine has led to a new generation of azolilum salts ideally suited for these powerful transformations and the identification of chiral variants for highly enantioselective reactions. The development of these thiamine-inspired catalysts, and their application to catalytic approaches to ester and amide bond formation, inverse electon-demand Diels-Alder reactions, gamma-lactone and gamma-lactam forming annulations, and a remarkable cascade catalysis approach to enantiopure cyclopentane derivatives will be described.