A catalyst don’t appear in the overall stoichiometry of the reaction it catalyzes, but it must appear in at least one of the elementary reactions in the mechanism for the catalyzed reaction. 58249-61-9, Name is Benzo[d]thiazole-6-carbonitrile, molecular formula is C8H4N2S. In a Article£¬once mentioned of 58249-61-9, Formula: C8H4N2S
Treatment of 4,5-bis(dlbromomethyl)thiazole (1a) with sodium iodide in DMF led to 4,5-bis(bromomethylene)-4,5-dihydrothiazole (2a). Trapping the latter in situ with dienophiles afforded directly the aromatized cycloadducts. Starting with 5-hydroxynaphthoquinone or its 2- and 3-bromo derivatives 6 gave a mixture of the tetracyclic quinones 10 + 11 from which the 1,6-regioisomer 10 predominates. Using acrylate dienophiles gave 6-substituted benzothiazoles 13 as the major products. The regiochemistry of the cycloadditions between 2a and naphthoquinones 6 agrees with the predictions of the frontier molecular orbital theory. In contrast, the regioselectivity observed from 2a and acrylate dienophiles 12, similar to that previously obtained with 5-bromomethylene-4-methylene-4,5-dihydrothiazole (2b), is opposite to that predicted and could be better accomodated by a competitive Michael addition followed by a cyclization-elimination step.
Treatment of 4,5-bis(dlbromomethyl)thiazole (1a) with sodium iodide in DMF led to 4,5-bis(bromomethylene)-4,5-dihydrothiazole (2a). Trapping the latter in situ with dienophiles afforded directly the aromatized cycloadducts. Starting with 5-hydroxynaphthoquinone or its 2- and 3-bromo derivatives 6 gave a mixture of the tetracyclic quinones 10 + 11 from which the 1,6-regioisomer 10 predominates. Using acrylate dienophiles gave 6-substituted benzothiazoles 13 as the major products. The regiochemistry of the cycloadditions between 2a and naphthoquinones 6 agrees with the predictions of the frontier molecular orbital theory. In contrast, the regioselectivity observed from 2a and acrylate dienophiles 12, similar to that previously obtained with 5-bromomethylene-4-methylene-4,5-dihydrothiazole (2b), is opposite to that predicted and could be better accomodated by a competitive Michael addition followed by a cyclization-elimination step.
Sometimes chemists are able to propose two or more mechanisms that are consistent with the available data.Formula: C8H4N2S, If a proposed mechanism predicts the wrong experimental rate law, however, the mechanism must be incorrect.Welcome to check out more blogs about 58249-61-9, in my other articles.
Reference£º
Thiazole | C3H7563NS – PubChem,
Thiazole | chemical compound | Britannica