A simple, green, and efficient approach was used to synthesize 3,4-dihydropyrimidines derivatives. We showed that the application of the planetary ball milling method with a ball-to-reagent weight ratio of 8 for the Biginelli reaction provides 3,4-dihydropyrimidines derivatives with excellent yields (>98%) in a short reaction time from the one-pot, three-component condensation of aldehydes, eth...

The title compound, C(14)H(19)N(3)O(2)S, was obtained from a condensation reaction of N-(p-tol-yl)hydrazinecarbothio-amide and ethyl acetoacetate. The mol-ecule assumes an E configuration; the thio-semicarbazide and ester groups are located on the opposite sides of the C=N bond. The almost planar thio-semicarbazide unit (r.m.s. deviation = 0.0130 Å) is tilted at a dihedral angle of 49.54 (12)° ...

in this study, an efficient and green process for the synthesis of dihydropyrimidin-2(1h)-ones from aromatic benzaldehydes, ethyl acetoacetate and urea using al-mcm-41 as heterogeneous catalyst and microreactor under solvent-free conditions has been developed. the advantages of this method are easy work-up procedure, regeneration of the catalyst, clean and neutral reaction conditions.

Bioreduction of several prochiral carbonylic compounds such as acetophenone (1), ethyl acetoacetate (2) and ethyl phenylpropionate (3) to the corresponding optically active sec-alcohols 1a-3a was performed using wild-type strains of Pichia pastoris UBB 1500, Rhodotorula sp., and Saccharomyces cerevisiae. The reductions showed moderate to excellent conversion and high enantiomeric excess, in an ...

The CuSnO3:SiO2 catalyst was synthesized by hydrothermal method. polycrystalline products were analyzed using various physical investigative techniques including XRD, SEM, TEM and BET surface area. present study deals with one-pot, four component reaction of aldehydes, malononitrile hydrazine hydrate ethyl acetoacetate in the presence catalytic amount Silica grafted CuSnO3 ethanol at 70°C to pr...

A variety of arylhydrazonopyridinones were prepared via heating cyanoacetamides with ethyl acetoacetate in absence of solvent under reflux conventionally or ultrasound irradiation or in a microwave oven. The formed products 5 and 6 could be readily converted to thienopyridones. Attempted addition of the latter to electron poor olefins afforded only arylhydrazonopyridinones.

Two efficient and convenient procedures for the synthesis of 6-amino-3-methyl-1,4-diphenyl-1,4-dihydropyrano[2,3c]pyrazole-5-carbonitrile derivatives based on four-component reaction involving ethyl acetoacetate, phenylhydrazine, malononitrile, and various aromatic aldehydes using trichloroacetic acid or ceric sulfate as heterogeneous catalysts in excellent yields and short reaction times have ...

6-Formyl-7-hydroxy-5-methoxy-2-methylchromone on bromination yields the 8-bromo deriva­ tive or the 8-bromo-6-formyl-5,7-dihydroxy derivative depending on the reaction condition. Cyclization of both leads to the corresponding 3-acetyl-, 3-benzoyl-, 3-carboxamido-, 3-carbethoxybenzodipyran derivatives. The 3-acetylbenzodipyran derivative when treated with ethyl acetoacetate or ethyl cyanoacetate...

In this study, an efficient and green process for the synthesis of dihydropyrimidin-2(1H)-ones from aromatic benzaldehydes, ethyl acetoacetate and urea using Al-MCM-41 as heterogeneous catalyst and microreactor under solvent-free conditions has been developed. The advantages of this method are easy work-up procedure, regeneration of the catalyst, clean and neutral reaction conditions.