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REACTIONS OF β-CARBONYL-SUBSTITUTED 4H-CHROMENES AND 1H-BENZO[f]CHROMENES WITH 5-AMINOPYRAZOLES

Виталий А. Осянин, Дмитрий В. Осипов, Кирилл С. Корженко, Олег П. Демидов, Юрий Н. Климочкин
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Abstract


A method for the preparation of pyrazolo[1,5-a]pyrimidines containing a 2-hydroxybenzyl or (2-hydroxynaphthalen-1-yl)methyl group in position 6 based on the reaction of β-carbonyl-substituted 4H-chromenes and their benzo analogs with 5-aminopyrazoles is proposed. A new type of ring-chain tautomerism with the participation of 7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidines was discovered.

Keywords


5-amino-1H-pyrazoles; 1H-benzo[f]chromene; β-carbonyl-substituted chromene; 4H-chromene; pyrazolo[1,5-a]pyrimidines; aza-Michael reaction; (3+3) cyclocondensation; tautomerism.

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