A mild, efficient, and environmentally green protocol for the synthesis of 2‐tosyloxyphenylpyran derivatives 3, 4, 5, 6, 7, 8, 9, 10, 11 via reaction of 2‐tosyloxybenzaldehyde (1) with malononitrile and some ketonic reagents in one‐pot, three component reaction within few minutes under stirring in methanol in presence of ammonium hydroxide solution or ultrasonic irradiation. On the other hand, the same products 3, 4, 5, 6, 7, 8, 9, 10, 11 were obtained by traditional method, on treatment of 2‐tosyloxybenzilidinemalononitrile (2) with the same ketonic reagents in refluxing ethanol in presence of TEA. 2‐Tosyloxyphenylpyranopyrazoles 12 and 13 were obtained via treatment of compound 1 with malononitrile, hydrazine hydrate or phenyl hydrazine and ethyl acetoacetate, in one‐pot, multicomponent reaction (MCRs). The structures of the new compounds were elucidated by elemental and spectral analyses. The newly synthesized compounds showed promising anti‐inflammatory activity.

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Condensation of 1-phenylpyrazolidine-3,5-dione 1 with 3-formylchromone afforded 4-(chromenylmethylene)pyrazolidinedione 2, which was reacted with hydrazine or hydroxylamine in different molar ratios and conditions to give the corresponding pyrazole and isoxazole derivatives 3-8, respectively. Compound 2 was subject to react with ammonia, N,S-or S,S-acetals, mercaptoacetic acid, cyanoacetamide or cyanothioacetamide to give the corresponding pyridine, dithiine, thiazine and thiophene, 9-14, respectively. The reaction of compound 2 with thiourea, guanidine, cystamine, o-aminothiophenol, ethylenediamine, o-phenelenediamine or barbituric acid afforded the corresponding thiazine, pyrimidine, thiazepine, diazepine, and pyran derivatives 17-23, respectively. The study of the reaction of compound 2 with nucleophiles via chromene ring opening was investigated.

New series of chromenes 2–4, pyridines 5–8, and pyranopyrazoles 9a,b were synthesized via one‐pot multicomponent reaction of 4‐tosyloxybenzaldehyde (1) and malononitrile with phenols, amines or hydrazines, and ethyl acetoacetate, respectively. Compound 9a was reacted with acetic anhydride, formic acid, or formamide to afford N‐acetyl derivative 10 and pyrazolopyranopyrimidines 11–13, respectively. Imidazole derivatives 14 and 15a–d were obtained by multicomponent reaction between compound 1 with ammonium acetate and benzil or aromatic amines in (1:2:1) or (1:1:1:1) ratio, respectively. The structures of new compounds were elucidated by elemental and spectral analyses.

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