Pyranopyrazoles. II. Synthesis and reactions of 1H, 6H??pyrano [2, 3??c] pyrazol??6??ones

MA Khan, AG Cosenza, GP Ellis

Index: Khan, Misbahul Ain; Cosenza, Alina Guerra; Ellis, Gwynn Pennant Journal of Heterocyclic Chemistry, 1982 , vol. 19, p. 1077 - 1085

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Citation Number: 25

Abstract

Abstract Various 1H, 6H-pyrano [2, 3-c] pyrazol-6-ones (III-XXIII) were obtained from β-keto esters and 1H-pyrazol-5-ones or hydrazines. Nitrations, chlorinations and brominations of these pyranopyrazoles were also carried out giving the corresponding derivatives (XXIV- LXIV). The pyrone ring is the more reactive one in these reactions and the preferred position of attack is the 5-position. The substitution products are formed by the addition-elimination ...