Despite prior reports of several really effective catalytic and non-catalytic approaches towards Biginelli's 3,4-dihydropyrimidin-2(1H)-ones, an overwhelming number of new catalysts for the Biginelli reaction have been recently published. Most of the catalysts are somewhat exotic, expensive, harmful and even uneffective in the absence of acidic additives. Herein we reduce the "yet-another-one-catalyst" idea to absurdity by proposing NaCl promotes the reaction that actually requires no catalyst, neither rare nor expensive.

No abstract

Several 5-cinnamoyl-and 5-(ethoxycarbonyl)-6-styryl derivatives of 4-aryl-3,4-dihydropyrimidin-2(1H)-ones were obtained and their physicochemical properties were investigated. The introduction of alkyl substituent in position 1 of dihydropyrimidine ring was shown to promote the Claisen-Schmidt reaction on acetyl group only; without the alkyl both acetyl and 6-methyl groups participate in the reaction.

No abstract

Colloids of elongated γ-Fe 2 O 3 magnetic nanoparticles (NPs) in a ferroelectric liquid crystal (FLC) were studied. Decreasing the dielectric strength of the Goldstone mode and changing the value of Cole-Cole parameter were found in the suspensions. It was also shown that the effect of introducing magnetic particles into a FLC consists of increasing the electric field strength magnitude required for unwinding its helical structure. Effect of magnetic field on dielectric properties of the FLC colloid was also studied. Dielectric constant measured under static magnetic field is different for the FLC host and FLC doped with the NPs.

No abstract

A novel catalyst-free synthetic approach to 1,2,3-triazolobenzodiazepinones has been developed and optimized. The Ugi reaction of 2-azidobenzaldehyde, various amines, isocyanides, and acids followed by microwave-assisted intramolecular azide–alkyne cycloaddition (IAAC) gave a series of target heterocyclic compounds in moderate to excellent yields. Surprisingly, the normally required ruthenium-based catalysts were found to not affect the IAAC, only making isolation of the target compounds harder while the microwave-assisted catalyst-free conditions were effective for both terminal and non-terminal alkynes.

New pyrazolopyrimidines and pyrazoloquinazolines were synthesized through the uncatalyzed reaction of 5-amino-3-arylpyrazole-4-carbonitriles with aldehydes and 1,3-dicarbonyl compounds.