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A facile one-pot synthesis of 5-(trifluoromethyl)-4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives is described via a three-component reaction of aldehydes with 5-aminotetrazole and ethyl 4,4,4-trifluoro-3-oxobutanoate or 4,4,4-trifluoro-1-phenylbutane-1,3-dione in ionic liquid. This method has the advantages of short synthetic route, operational simplicities, good yields, ecofriendliness, and recyclability of the solvent.

An efficient and facile synthesis of 4,6-diarylpyrimidin-2(1H)-one via a Biginelli-like reaction of aromatic aldehydes, aromatic ketones, and urea in the presence of NaOH under solvent-free conditions using a heating method has been developed. Compared with the classical reaction conditions, this new synthetic method has the advantages of excellent yields, shorter reaction time, and mild reaction conditions.

A series of new pyrazolo[3,4-f]quinoline derivatives were synthesized by multicomponent reactions of equimolar amounts of aromatic aldehydes 1, barbituric acids 2 (barbituric acid or 1,3-dimethyl barbituric acid), and 5-aminoindazole 3 in mixed solvent of glacial acetic acid and ethylene glycol (2:1, v/v) without catalyst under microwave irradiation. This one-pot protocol has the advantage of good yields (91–94%), simple workup procedure, and short reaction times (5–6 min).

A green approach to the synthesis of arylidene-substituted spiro[4,5]decan-8-one derivatives was successfully realized via the mild, base-catalyzed reaction of aromatic aldehydes with 1,4-dioxa-spiro[4.5]decan-8-one in water under microwave irradiation. This protocol has the prominent advantages of environmental friendliness, short reaction time, excellent yields, low cost, easy operation, and broad scope of applicability.

An efficient and convenient method for the preparation of 2,4-diamino-6-arylpyrimidine-5-carbonitrile derivatives by the one-pot reaction of aromatic aldehydes, malononitrile, and guanidine carbonate, in the presence of sodium hydroxide under solvent-free conditions, was reported. This method has the advantages of excellent yields, mild reaction conditions, easy work up, and environmental friendliness over the existing procedures.

An unexpected and green synthesis of azapodophyllotoxin derivatives was realized via microwave-assisted multicomponent reactions of dimedone, tetronic acid, and aromatic aldehydes in ammonia water. This protocol has the advantages of environmental friendliness, short reaction time, good yields, low cost, and easy operation.

A green approach to the synthesis of polyfunctionalized pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidines was successfully realized via multicomponent reactions of aldehydes, 3-methyl-1-phenyl-1H-pyrazol-5-amine, and 1-methylbarbituric acid in water under microwave irradiation without catalyst. This protocol has the prominent advantages of environmental friendliness, short reaction time, excellent yields, low cost, easy operation, and broad scope of applicability.

A versatile and efficient route to 3-amino-1-aryl-9H-fluorene-2,4-dicarbonitrile via multicomponent reactions of 1-indanone, aromatic aldehydes, and malononitrile under solvent-free conditions using NaOH as the catalyst is described. This method provides several advantages over alternative procedures such as mild, solvent-free conditions at ambient temperature and direct isolation of the products in good yields.

A series of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-pyridine-3-carbo-nitriles were synthesized by the one-pot, multicomponent reaction of 3-acetyl-coumarin, aromatic aldehydes, malononitrile, and ammonium acetate in acetic acid under microwave irradiation. The reactions were completed in 10–13 min with 61–86% yields, were environmental benign, and had easy workup. Their structures were confirmed by 1H NMR, IR, and MS spectra and elemental analysis.

A simple KF/Al2O3-catalyzed reaction of 1,3-diaryl-2-propen-1-one and 2,6-diamino-4-hydroxylpyrimidine in ethyl alcohol gave aromatized 5,7-diarylpyrido[2,3-d]pyrimidine derivative by air oxidation. On the other hand, the unaromatized intermediate products were isolated under dry nitrogen successfully. A possible reaction mechanism with two pathways to lose water was proposed based on the further experimental results; one of them was confirmed by 1H NMR spectra of isolated intermediate product.

The uncatalyzed and three‐component reaction of arylaldehyde, malonodinitrile, and 3‐arylamino‐5,5‐dimethylcyclohex‐2‐enone at 160 °C under solvent‐free conditions gave 1,4‐diarylquinoline derivatives in high yields.

A convenient, environmentally friendly, and solvent‐free procedure has been developed for the synthesis of 3‐amino‐2,4‐dicarbonitrile‐5‐methylbiphenyl derivatives. Compared with the classical reaction condition, this new synthetic method has the advantages of excellent yields, easy setup, mild reaction conditions, and environmental friendlines.

An efficient and facile synthesis of 4,6‐diaryl‐2‐oxo‐1,2‐dihydropyridine‐3‐carbonitriles via three‐component cyclocondensation from aromatic aldehydes, aromatic ketones, and 2‐cyanoacetamide under solvent‐free conditions is described. The mild reaction conditions, simple protocol, and clean reaction make this protocol practical and economically attractive.

A facile parallel synthesis of 2‐amino‐4,6‐diarylbenzene‐1,3‐dicarbonitrile derivatives via a one‐pot reaction of aromatic aldehydes, aromatic ketone, and malononitrile under solvent‐free conditions has been developed. This new protocol has the advantages of shorter time, higher yields, lower cost, and environmental friendliness.

A fast and efficient synthetic method for the title compounds is described. By heating aromatic aldehyde and triacetic acid lactone in ethylene glycol under microwave irradiation without catalyst for 3–5 min, 10‐aryl‐2,7‐dimethyl‐4,5‐dioxo‐3,6,9‐trioxa‐3,4,5,6,9,10‐hexahydroanthracenes were afforded with high yields.

A simple, efficient, and general method has been developed for the synthesis of coumarin derivatives through a one‐pot reaction of aromatic aldehydes, 2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione and 5,5‐dimethyl‐1,3‐cyclohexanedione, in the presence of TEBA under solvent‐free conditions using grinding methods. The mild reaction conditions, simple protocol, high yields, and cleaner reaction make this protocol practical and economically attractive.

Knoevenagel condensation of aromatic aldehydes with active methylene compounds under solvent‐free conditions to synthesize arylidene compounds by grinding in the presence of TEBA at room temperature has been described. This method is simple, efficient, and environmentally friendly.

A range of tetrahydrobenzo[b]pyrans have been synthesized in very good yields under solvent‐free conditions by grinding α‐cyanocinnamonitrils or β‐cyano‐β‐carbethoxy styrene and 5,5‐dimethyl‐1,3‐cyclohexanedione in the presence of TEBA as catalyst. The short reaction time, cleaner reaction, and easy workup make this protocol practical and economically attractive.

A short and simple synthesis of chromeno[4,3‐b]benzo[f]quinolin‐6‐one derivatives was accomplished in good to high yields via the reaction of N‐arylidenenaphthalen‐2‐amine with 4‐hydroxycoumarin in aqueous media catalyzed by TEBAC. The structures were established by spectroscopic data and further confirmed by X‐ray analysis. In addition, water was chosen as a green solvent.

A series of pyrido[2,3‐d]pyrimidine derivatives were synthesized by the three‐component reaction of arylaldehyde, cyanoacetate, and 4‐amino‐2,6‐dihydroxylpyrimidine in ethyl alcohol at 80°C catalyzed by KF‐Al2O3. It was interesting that further aromatization took place automatically. Compared with other synthetic methods, this new method has the advantage of easier workup, milder reaction conditions, and good yields.

A series of 2‐aryl‐4,5‐diphenylimidazoles were synthesized by a one‐step condensation reaction of benzil, aromatic aldehyde, and ammonium acetate in acetic acid under microwave irradiation. The reactions were completed in 4–11 min with good yields and easy workup.

A series of 2‐aminochromene derivatives include 2‐aminobenzo‐[h]chromene and naphtha[1,2‐b;6,5‐b′]dipyrans derivatives were synthesized from arylaldehyde, malononitrile or ethyl cyanoacetate with 1‐naphthol or 1,5‐naphthalenediol in refluxing ethyl alcohol catalyzed by KF‐Al2O3. The structure of the products was confirmed by X‐ray analysis.

A series of 5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran derivatives were prepared by the reaction of arylmethylidenemalononitriles or 2-cyano-3-aryl-l-acrylate with 5,5-dimethyl-1,3-cyclohexanedione (dimedone) in DMF at room temperature catalyzed by KF-alumina. The structure of the product was confirmed by X-ray analysis.

A series of 2-amino-5,6,7,8-tetrahydro-5-oxo-4-aryl-7,7-dimethyl-4H-benzo-[b]-pyran-3-ethylcarboxylates were synthesized by reaction of β-cyano-β-carbothoxy styrene and 5,5-dimethyl-1,3-cyclo-hexanedione under microwave irradiation without catalyst and solvent.

A convenient synthetic method for the title compounds are described. Heating 1, 2 and 3 under microwave irradiation for 3–5 min to afford 4. The structure of the compound 4c has been thoroughly studied by X-ray crystallographic analysis.

A series of substituted pyrano[2,3-c]pyrazole derivatives were synthesized by the one pot reaction of aromatic aldehydes, malononitrile and 3-methyl-1-phenyl-2-pyrazolin-5-one under microwave irradiation in good yields.

A convenient synthetic method for substituted 2,5-dioxo-1,2,3,4,5,6,7,8-octahydroquinolines is described. Heating Meldrum's acid, dimedone, ammonium acetate and different aromatic aldehydes without a solvent in a microwave irradiation for 2–5 minutes affords 4 in 72–86% yield. The structure of these compounds has been thoroughly studied by x-ray crystallographic analysis.

A series of (3-oxo-1,3-diaryl) propylpropanedinitriles were synthesized by Michael addition reaction of chalcones and malononitriles in the presence of potassium fluoride on alumina.

A series of 3-aryl-3-(5,5-dimethyl-3-hydroxy-2-cyclohexene-1-one-2-yl) propanic esters were synthesized by reaction of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione and isopropylidene malonate in alcohols catalyzed by KF-Al2O3. The structure of 4a was determined by X-ray analysis.