The thiazolium catalyzed benzoin condensation with mild base does not involve a 'dimer' inermediate

Article abstract of DOI:10.1016/S0040-4039(00)75794-7

Kinetic studies show that the benzoin condensation catalyzed by 3,4,5-trimethylthiazolium iodide and triethylamine in DMSO has a transition state with two benzaldehyde and one thiazolium components, while the conversion of nitrobenzaldehyde to the thiazol