A facile and efficient method for the preparation of 1,1-diacetates of aldehydes is improved. The acidified kaolin with sulfuric acid (2 % w/w) catalyzed 1,1-diacetates formation from aldehydes in solvent-free conditions. Both aromatic and aliphatic aldehydes gave high yields (85-95 %) of the corresponding 1, 1-diacetates. Advantages of this method are the use of inexpensive and selective catal...

the present study aimed to use a method for the synthesis of some 3, 4-dihydropyrimidin-2-(1h) - ones/thiones. the study tried to answer the question whether this reaction can be performed without solvent and with new catalyst or not. to find answer to the question, we described a novel protocol for the efficient synthesis of 3, 4-dihydropyrimidin-2-(1h)-one derivatives using aromatic aldehyde,...

Effective methodologies for efficient preparation of semicarbazones from aldehydes or ketones via milling and the subsequent regeneration of the parent carbonyls by gaseous nitrogen dioxide are described under solid-solid and gas-solid reaction conditions, respectively. These methods are fast, simple and environmentally benign which do not require the use of any auxiliaries such as catalyst...

3-methyl-1-sulfonic acid imidazolium tetrachloroferrate {[Msim]FeCl4} as an efficient sulfur catalyst was prepared and applied, as an efficient catalyst, for the cross-aldol condensation reaction between cycloalkanones and arylaldehydes to give α,αʹ- bis(arylidene)cycloalkanones in high yields and short reaction times at 75 °C under solvent-free conditions. 3-methyl-1-sulfonic acid imidazolium...

phthalocyanine complexes of cu, co, ni, fe, zn, pd, pt and ru have been synthesized from reaction between phthalonitrile and proper metal salts upon exposure to microwave irradiation under solvent-free conditions and considerably reduced reaction times.

Phthalocyanine complexes of Cu, Co, Ni, Fe, Zn, Pd, Pt and Ru have been synthesized from reaction between phthalonitrile and proper metal salts upon exposure to microwave irradiation under solvent-free conditions and considerably reduced reaction times.

a practical and green method for the synthesis of 5h-dibenzo[b,i]xanthene-tetraones and spiro[dibenzo[b,i]xanthene-13,3'-indoline]-pentaones by the condensation of 2-hydroxynaphthalene-1,4-dione with aldehydes or isatins, respectively, in the presence of a catalytic amount of cellulose sulfuric acid (csa) under solvent-free conditions at 100 °c is described. the significant features of this pro...

a green and efficient one pot, three component protocol for synthesis of naphthopyranopyrimidines by cyclocondensation of β-naphthol, aldehyde, and 6-amino-1,3-dimethyluracil using l-proline as a beneficial catalyst with high catalytic activity under solvent-free conditions at 100 °c is described. in this study, several types of aromatic aldehyde, containing electron-withdrawing groups as well ...

protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and acetylenic esters, by nh-acids such as azathioprine, imidazole or theophylline leads to the formation of vinyltriphenylphosphonium salts, which undergo a michael addition reaction with a conjugate base to produce phosphorus ylides. silica nanoparticles (silica nps were prepared by therm...

An efficient sodium bismuthate (NaBiO3) synthesis of biologically active spiro[4H-pyran]derivatives has been accomplished via one-pot three-condensation of isatin/acenaphthequinone, malononitrile and different reagents including 1,3-dicrbonyl compounds, α-naphthol and 4-hydroxycumarin under solvent-free conditions. The notable advantages of the present procedure are: eco-friendly, environmental...