Two thiazolium compounds were synthesized specifically labeled at their C2 positions: 3, 4, 5-trimethy1 [2-lsC] thiazOlium nitrate and 3-benzyl-b (B-ethoxyethyl)-4methyl [2-'gC] thiazoliu bromide, with a view to examine their pathways leading to dimerization in strongly basic medium using 19C NMR. On addition of less than 1 equiv of base the N-methyl ion fist formed an unsymmetrical dimer in which the C2 atom of two molecules were bonded to ...
