Shu-Jiang Tu

A Convenient Synthesis of 5-Oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran Derivatives Catalyzed by KF-Alumina

Abstract 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.

Synthesis of 2-aminochromene derivatives catalyzed by KF/Al2O3

Abstract 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.

Efficient Green Procedure for the Knoevenagel Condensation under Solvent‐Free Conditions

Abstract 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.

Efficient Synthesis of Tetrahydrobenzo[b]pyrans under Solvent‐Free Conditions at Room Temperature

Abstract 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 facile synthesis of 1,2-dihydroquinazolin-4(3H)-ones with the aid of a low-valent titanium reagent

A short and facile synthesis of a series of 1,2-dihydroquiazolin-4(3H)-ones was accomplished in good yields via the novel reductive cyclisation of o-nitrobenzamides with aldehydes or ketones promoted by the TiCl4/Sm system. Structures were established on the basis of elemental analysis, IR, 1H NMR and confirmed by a single-crystal X-ray diffraction analysis. The advantages of our method are easily accessible starting materials, convenient manipulation and moderate to high yields.

A CONVENIENT SYNTHESIS OF 2,4-DIARYLPOLYHYDROQUINOLINE DERIVATIONS IN THE PRESENCE OF AMMONIUM ACETATE

ABSTRACT A series of substituted 5-oxo-1,2,3,4,5,6,7,8-octahydroquinoline derivatives have been synthesized from 5,5-dimethyl-1,3-cyclohexane-dione (dimedone) and 1,3-diaryl-2-propen-1-one in DMF at 80°C in the presence of ammonium acetate with high yields (64–98%), the structure of the product was confirmed by X-ray analysis.

Three‐Component, One‐Pot Synthesis of Pyrido[2,3‐d]pyrimidine Derivatives Catalyzed by KF‐alumina

Abstract 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.

Simple Procedure for the Synthesis of Arylmethylenemalononitrile Without Catalyst

Abstract Knoevenagel condensation of malononitrile with aromatic aldehydes can be achieved at room temperature in the absence of catalysts in short time, and the products of arylmethylenemalononitriles were isolated in a practically pure form without further purification.

One‐Pot Synthesis of 4,6‐Diaryl‐2‐oxo‐1,2‐dihydropyridine‐3‐carbonitriles via Three‐Component Cyclocondensation under Solvent‐Free Conditions

Abstract 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.

EFFICIENT SYNTHESIS OF 6-AMINO-8-ARYL-2-METHYL-1,2,3,4-TETRAHYDROISOQUINOLINE-5,7-DICARBONITRILE UNDER SOLVENT-FREE CONDITIONS

A series of 6-amino-8-aryl-2-methyl-1,2,3,4-tetrahydroisoquinoline-5,7-dicarbonitriles were prepared in good yields under solvent-free conditions by multicomponent reactions of aromatic aldehyde, malononitrile, and 1-methylpiperidin-4-one in the presence of sodium hydroxide (NaOH). The structures of the products were characterized by infrared, 1H NMR spectra, elemental analysis, and high-resolution mass spectrometery (HRMS).