Synthesis of five- and six-membered lactams via solvent-free microwave Ugi reaction

Five- and six-membered lactams were synthesized via a 4-center 3-component Ugi reaction by combining amines, isocyanides, and ketoacids under solvent-free microwave conditions. The reaction was carried out in much shorter times and the yields were improved in comparison to classical conditions.     

Yb（OTf）3-catalyzed synthesis of pyrroles under solvent-free conditions

A Yb(OTf)_3-catalyzed approach for the synthesis of pyrroles under solvent-free conditions was achieved,which could afford the desired products with yields ranged from moderate to excellent.     

Catalyst- and solvent-free coupling of 2-methyl quinazolinones and 3-(trifluoroacetyl)coumarins: An environmentally benign access of quinazolinone derivatives

An environmentally benign highly atom-economic protocol for the construction of the CC bond has been developed under catalyst- and solvent-free conditions. This protocol involves the efficient coupling of 2-methyl quinazolinones with 3-(trifluoroacetyl)coumarins for the access of quinazolinone derivatives in excellent yields (up to 90 %). The crystal structure of compound 3di was investigated by X-ray diffraction analysis. The biological activities, such as in vitro antifungal activity of the quinazolinone derivatives against Fusarium graminearum, Fusarium moniliforme, Fusarium oxysporum, Phytophthora parasitica var nicotianae, and Rhizoctonia solani Kuhn, were investigated. The bioassay results indicated that most of the target products exhibited promising fungicidal activities, and compound 3 cl exhibited 95 % fungicidal activity against R. solani, with an EC₅₀ value of 10.6 μg/mL.     

Effect of Vanadium on Phosphomolybdic acid structure and Catalytic evaluation of Solvent-free synthesis of 4-tert-butylphenol

Vanadium-modified phosphomolybdic acid (PMA) with different vanadium-to-phosphorus (V/P) mole ratio materials were synthesised and characterised by various techniques. XRD results established the formation of crystallite Keggin ions. Raman and FT-IR spectra data confirm the Keggin ion of heteropoly acid is retained after V loading into the PMA structure. TPD profile showed higher acidity at a lower V/P ratio than higher loadings. BET analysis showed a higher surface area at a lower V/P mole ratio than higher catalyst loadings. We evaluated the efficacy of the prepared materials as catalysts for the tertiary butylation of phenol. The lower V/P mole ratio material exhibited higher conversion and selectivity towards 4-tert-butyl phenol than other loadings. These findings support that V loading modifies the acidity of PMA, and the material demonstrates enhanced catalytic activity towards the desired product.