An efficient synthesis of quinalone-3-(N-phenylpyrazoles) and quinalone-3-cyclohexadienone derivatives

作者：Darsi S S Praveen Kumar^*; Kumar K Shiva; Devi B Rama; Naidu A; Dubey P K

来源：Indian Journal of Chemistry - Section B: Organic and Medicinal Chemistry , 2013, 52(8): 1146-1151.

• 2-Chloroquinoline-3-carboxaldehyde
• 3-formyl-2(1H)-quinalone
• phenylhydrazine
• acetoacetanilide
• chloranil

An efficient synthesis of quinalone-3-(N-phenylpyrazoles) 5 and quinalone-3-(cyclohexadienones) 8 has been described. 2-Chloroquinoline-3-carboxaldehyde 1, on reaction with 4N HCl gives 3-formyl-2(1H)-quinalone 2. The latter is reacted with acetophenone in the presence of NaOH as base to yield the corresponding quinalone-3-chalcone 3 which on treatment with phenylhydrazine gives 3-(dihydropyrazolo)quinolone 4. Dehydrogenation of 4 with chloranil yields the corresponding 5. Compound 3 on bromination yields the dibromo derivative 6 which on treatment with phenylhydrazine directly yields 5. On the other hand, 3 on treatment with acetoacetanilide in methanol using acetic acid as a catalyst affords the corresponding quinalone-3-(cyclohexenone) derivatives 7 which on dehydrogenation with chloranil, affords the corresponding 8 in excellent yield.

• 出版日期2013-8