Qiya Zhuang

Synthesis of quinazolin-4(3H)-ones and 1,2-dihydroquinazolin-4(3H)-ones with the aid of a low-valent titanium reagent

Abstract A short and facile synthesis of a series of quinazolin-4(3H)-ones and 1,2-dihydroquinazolin-4(3H)-ones was accomplished in good yields via the novel reductive cyclization of o-nitrobenzamides and triethyl orthoformate, aldehydes or ketones promoted by TiCl4/Zn.

Three‐Component One‐Pot Synthesis of 1,4‐Dihydropyrano[2,3‐c]pyrazole Derivatives in Aqueous Media

Abstract 6‐Amino‐5‐cyano‐4‐aryl‐1,4‐dihydropyrano[2,3‐c]pyrazoles were synthesized by three‐component reaction of aromatic aldehydes, malononitrile, and 3‐methyl‐1‐phenyl‐2‐pyrazolin‐5‐one using triethylbenzylammonium chloride (TEBA) as catalyst in aqueous media. The reaction has the advantages of good yield, less pollution, ease of separation, and of being environment friendly.

One-pot synthesis of 2-amino-4-aryl-5-oxo-5,6,7,8-tetrahydro-4H-1- benzopyran-3-carbonitriles in aqueous media

The reaction of aromatic aldehyde, malononitrile and 1,3-cyclohexanediones in water in the presence of triethylbenzyl-ammonium chloride (TEBA) provides an efficient access to 3-cyano-substituted 2-amino-4-aryl-4,6,7,8-tetrahydro-5H-1-benzopyran-5-ones.

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.

Three-component processes for the synthesis of 4-aryl-7,7-dimethyl- 5-oxo-3,4,5,6,7,8-hexahydrocoumarin in aqueous media

The reaction of an aromatic aldehyde, isopropylidene malonate and 5,5-dimethyl-1,3-cyclohexanedione in water in the presence of triethylbenzylammonium chloride (TEBA) as catalyst affords a one-pot synthesis of 4-aryl-7,7-dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin.

Reaction of Imines with 5,5‐Dimethyl‐1, 3‐cyclohexandione

Abstract The reaction of imines 1 with 5,5‐dimethyl‐1,3‐cyclohexandione 2 in methanol was investigated. When the reaction was carried out without a catalytic amount of molecular iodine, ring‐opening derivatives of xanthenediones 3 were obtained in high yields. On the other hand, when molecular iodine and a catalytic amount of zinc powder were employed as the catalyst, xanthenediones derivatives 4 were obtained with excellent yields.

Synthesis of 4H,5H-pyrano[3,2-c][1]benzopyran-5-ones in aqueous media

The reaction of substituted cinnamonitriles with 4-hydroxycoumarin in water in the presence of triethylbenzyl-ammonium chloride affords 2-amino-4-aryl-4H,5H-pyrano [3,2-c] [1]benzopyran-5-one derivatives.

Facile Synthesis of Substituted Quinazolin‐4‐(3H)‐ones Using Low‐Valence Titanium Reagent

Abstract A short and facile synthesis of a series of 3‐aryl quinazolin‐4‐(3H)‐ones was accomplished in good yields via the intermolecular reductive coupling reaction of N‐aryl‐2‐nitrobenzamide and triethyl orthoformate promoted by TiCl4/Zn.