Synthesis and reactions of heterocyclic azide derivatives. 6. Reactions of benzothiazole azides with 1,3-diketones and iotisch complexes

✍ Scribed by I. A. Ol'shevskaya; M. Yu. Kornilov; M. N. Smirnov

• Publisher: Springer US
• Year: 1990
• Tongue: English
• Weight: 259 KB
• Volume: 26
• Category: Article
• ISSN: 0009-3122
• DOI: 10.1007/bf00480876

✦ Synopsis

Cycloaddition of 5-and 6-azido-2-methylbenzothiazoles to magnesiumbromoacetylenes and 1,3-diketones leads to the formation of 2-methyl-5( 6)- (1,2,3-triazol-l-yl)benzothiazoles. Reaction with benzoylacetone, for instance, results in the formation of two isomeric 4-acyl-l,2,3-triazoles, which differ in the position of the methyl and phenyl substituent radicals.

Dimroth [2, 3] has carried out the synthesis of 1,2,3-triazoles based on the reaction of phenyi azide with acetylene and its derivatives. Our attempts to utilize acetylene and its homologs in reactions with 5-and 6-azido-2-methylbenzothi~oles (I and II) did not produce the desired results, however. In contrast, using more active Iotisch complexes, bromomagnesiummethyland bromomagnesiumphenylacetylenes, in place of acetylenic hydrocarbons in reactions with azides I and II, we were able to obtain the desired 1,5-disubstituted 1,2,3-triazoles III-V.