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Davis-Beirut reaction: route to thiazolo-, thiazino-, and thiazepino-2H-indazoles.

ABSTRACT: Methods for the construction of thiazolo-, thiazino-, and thiazepino-2H-indazoles from o-nitrobenzaldehydes or o-nitrobenzyl bromides and S-trityl-protected 1°-aminothioalkanes are reported. The process consists of formation of the requisite N-(2-nitrobenzyl)(tritylthio)alkylamine, subsequent deprotection of the trityl moiety with TFA, and immediate treatment with aq. KOH in methanol under Davis-Beirut reaction conditions to deliver the target thiazolo-, thiazino-, or thiazepino-2H-indazole in good overall yield. Subsequent S-oxidation gives the corresponding sulfone.

SUBMITTER: Farber KM

PROVIDER: S-EPMC4120971 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Davis-Beirut reaction: route to thiazolo-, thiazino-, and thiazepino-2H-indazoles.

Farber Kelli M KM Haddadin Makhluf J MJ Kurth Mark J MJ

The Journal of organic chemistry 20140723 15

Methods for the construction of thiazolo-, thiazino-, and thiazepino-2H-indazoles from o-nitrobenzaldehydes or o-nitrobenzyl bromides and S-trityl-protected 1°-aminothioalkanes are reported. The process consists of formation of the requisite N-(2-nitrobenzyl)(tritylthio)alkylamine, subsequent deprotection of the trityl moiety with TFA, and immediate treatment with aq. KOH in methanol under Davis-Beirut reaction conditions to deliver the target thiazolo-, thiazino-, or thiazepino-2H-indazole in g ...[more]

PMID: 25019525

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