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A series of triazolyl methoxyphenyl 1,8-dioxo-decahydroacridine derivatives has been prepared in a one-pot, pseudo-five-component reaction of aromatic propargylated aldehydes, various azides, dimedone, and a variety of amines in the presence of Cu(OAc)2/sodium ascorbate and 1-methylimidazolium trifluoroacetate ([Hmim]TFA) as the catalyst in good yields. [ABSTRACT FROM AUTHOR]

SBA-15 mesoporous silicas modified with proline and aminopropyl functional groups were employed for synthesis of tetrahydrobenzo[b]pyrane derivatives by simply mixing the precursors with surface-modified catalyst in a mortar. The mesoporous catalysts were characterized by Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), small-angle x-ray diffractometry (SAXS), thermogravimetric/differential thermal analyzer (TG/DTA), Barrett–Joiner–Halenda (BJH) pore size and volume analysis, and Brunauer–Emmett–Teller (BET) surface area measurement methods. The results indicate that SBA-15 mesoporous silica modified with proline and aminopropyl functional groups can be effectively utilized for synthesis of tetrahydrobenzo[b]pyrane derivatives. [ABSTRACT FROM AUTHOR]

Diazabicyclo[2.2.2]octane (DABCO) has been used as a mild and efficient catalyst for synthesis of 2-amino-3-cyano naphthopyran derivatives via a one-pot three-component reaction of aromatic aldehydes, naphthols, and malononitrile at room temperature. The short reaction times, easy workup, good to excellent yields, and mild reaction conditions make this domino Knoevenagel-Michael reaction both practical and attractive. [ABSTRACT FROM AUTHOR]

Diammonium hydrogen phosphate was used as a mild, efficient, neutral, and cheap catalyst for the synthesis of various 4H-benzo[b]pyran derivatives via a one-pot, three-component condensation of aromatic aldehydes, active methylene compounds, and dimedone in aqueous media. [ABSTRACT FROM AUTHOR]

Knoevenagel condensation of various aromatic and heteroaromatic aldehydes with active methylene compounds such as methyl and ethyl cyanoacetate, malononitrile, and cyanoacetamide proceeds smoothly with stirring in water in the presence of 4 mol% of diammonium hydrogen phosphate. The reactions were carried out at room temperature in short periods with a very simple workup procedure and good to high yields. [ABSTRACT FROM AUTHOR]

Tetra- n -butylammonium hydroxide (TBAH) has been utilized as a novel and efficient catalyst for the Knoevenagel condensation of aldehydes with acidic methylene compounds such as methyl- and ethylcyanoacetate, malononitrile, and cyanoacetamide to afford substituted olefins. [ABSTRACT FROM AUTHOR]