Supported Preyssler Nanoparticles in Synthesis of 1,3‐Diaryl‐5‐Spirohexahydropyrimidines

Silica‐supported Preyssler nanoparticles (H₁₄[NaP₅W₃₀O₁₁₀])/SiO₂ are used as a new and recyclable catalyst for the preparation of 1,3‐diaryl‐5‐spirohexahydropyrimidines via a one‐pot condensation of anilines, formaldehyde, and cyclohexanone.     

Ultrasound-promoted,rapid, green,one-pot synthesis of 2′-aminobenzothiazolomethylnaphthols via a multi-component reaction,catalyzed by heteropolyacid in aqueous media

A one-pot, three-component condensation reaction of 2-aminobenzothiazole, 2-naphthol and appropriate aldehydes catalyzed by heteropolyacid (HPA) in an aqueous medium afforded the Mannich adduct 2′-aminobenzothiazolomethylnaphthols at 45 °C under ultrasound irradiation. This method provides several advantages such as simple work-up procedure, short reaction time and high yields.     

Ferric Nitrate/Molibdatophosphoric Acid as a New and Efficient System in the Oxidative Deprotection of Trimethylsilyl Ethers to Corresponding Carbonyl Compounds under Solvent‐Free Conditions

Oxidative deprotection of a variety of trimethylsilyl ethers were performed by Fe(NO₃)₃.9H₂O in the presence of H₃PMo₁₂O₄₀.xH₂O as catalyst at room temperature in good to high yields under solvent‐free conditions.     

Dawson型磷钼钒杂多酸催化合成1,3-二噁戊烷的研究

考察了Dawson型磷钼钒杂多酸和各种结构反应底物对1，3-二噁戊烷合成催化活性的影响．研究表明：H6P2Mo17VO62的催化效果最好，反应条件温和，环氧化物的转化率接近100％，1，3-二噁戊烷的选择性在90％以上。     

SiO2与Keggin杂多酸相互作用的研究

采用经典酸化与乙醚萃取相结合的方法，制备了Keggin型杂多酸H3PMo12O40，并以SiO2为载体制备了经不同温度焙烧的负载型杂多酸样品，利用TG、DTA、IR、XPS、NH3－TPD等手段，对负载前后的杂多酸样品进行了表征；考察了SiO2与杂多酸之间的相互作用以及载体对杂多酸酸性的影响，研究发现，SiO2载体的引入，可以有效改善杂多酸的热稳定性，焙烧温度的升高，会显著降低杂多酸的酸性，并提出SiO2杂多酸的相互作用方式。     

H3PMo12O40 catalyzed three-component one-pot synthesis of 4,6-diarylpyrimidin-2(1H)-ones under solvent-free conditions

<正>4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amount of H_3PMo_(12)O_(40)under solvent-free conditions.     

Preparation and Characterization of Heteropoly-complex K_11[La(GaW_11O_39H_2)_2]· xH_2O

Heteropoly complexes K11[Ln(CaW 11O39H2)21 · x H2O(Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy ) have been prepared and analysed. Some properties such as thermal behavior, IK and UV spectra, X-ray powder diffraction, magnetic susceptibility and X-ray photoelectron spectrum have been investigated.     

Synthesis of 3-(aryl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one derivatives using heteropolyacids as green,heterogeneous and recyclable catalysts

Reaction of isatoic anhydride with aniline derivatives gave 2-amino-N-(aryl)benzamides.The latters reacted with phenyli-sothiocyanate in the presence of heteropolyacids in various solvents which afforded 3-(aryl)-2-thioxo-2,3-dihydroquinazolin- 4(1H)-one derivatives.The effects of various heteropolyacids including Preyssler and Keggin on the yields and reaction times have been investigated.     

Heteropolyacid as a New,Green and Recyclable Catalyst for the Synthesis of 2‐Aryl Benzoxazole under Solvent‐Free Conditions

A simple, convenient and general method has been developed for the synthesis of 2‐arylbenzoxazole via condensation of o‐aminophenols and benzoyl chloride derivatives under solvent‐free conditions in the presence of a catalytic amount of heteropolyacids in good yields.     

Regioselective Synthesis of 2-Substituted [1,2,4]Triazolo[5,1-b][1,3]thiazin-7-ones by Heteropolyacids

2-Substituted [1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones 3 were synthesized via regioselective cyclization of 4H-[1,2,4]triazol-3-ylsulfanyl-acrylic acids 2 in the presence of catalytic amounts of heteropolyacids at room temperature in very good yields and rates.