A simple and efficient method for the chemoselective 1,1-diacetate protection of aromatic aldehydes with acetic anhydride by using Ni2+ supported on hydroxyapatite-core-shell magnetic γ-Fe2O3 nanoparticles (γ-Fe2O3@HAp-Ni2+) under solvent free conditions. This method has several advantages, including high yield, short reaction time, simple work-up and recyclable property of the catalyst. The ca...

HAVE BEEN USING the method of Pearson, Stern, and McGavack (1) for the determination of cholesterol for some time. It has proved to be a convenient and accurate procedure and the reaction had always gone smoothly. One day recently, however, the tubes were set up for the determination as usual, using a freshly prepared solution of p-toluenesulfonic acid. Solutions made from the same bottle of so...

Plants release volatiles in response to caterpillar feeding that attract natural enemies of the herbivores, a tri-trophic interaction which has been considered an indirect plant defence against herbivores. The caterpillar-induced plant volatiles have been reported to repel or attract conspecific adult herbivores. To date however, no volatile signals that either repel or attract conspecific adul...

An efficient and one-pot procedure is described for the synthesis of a variety derivatives 1,2-dihydrobenzo[f]chromen-3-ones 3,4-dihydrochromen-2-ones under solvent-free conditions via pseudo-four-component domino reaction acetic anhydride, aryl aldehydes, glycine-based dithiocarbamates, phenols/naphthols in presence l-proline H4[Si(W3O10)4].xH2O as green catalysts. All products were made strat...

a simple and efficient method for the chemoselective 1,1-diacetate protection of aromatic aldehydes with acetic anhydride by using ni2+ supported on hydroxyapatite-core-shell magnetic γ-fe2o3 nanoparticles (γ-fe2o3@hap-ni2+) under solvent free conditions. this method has several advantages, including high yield, short reaction time, simple work-up and recyclable property of the catalyst. the ca...

The reaction of 5,6,7,8-tetrahydro-4H-cyclohepta[b]thiophene derivatives 3a,b with acetic anhydride in presence of glacial acetic acid produced the acetamido derivatives 4a,b. Cyclization of the latter compounds gave the annulated products 5a,b. Compounds 3a,b reacted with one of the activated methylene groups of malononitrile (2a) and afforded compounds 7a,b through internal cyclization of the...

The new 1,3,4-oxadiazolylquinoxaline ring system was synthesized by the condensation of the quinoxaline 1,4-dioxide acid hydrazide 6 with acetyl chloride in one-pot synthesis. In which the hydrazide was refluxed in excess of acetyl chloride, acetic anhydride or acetic acid in the presence of phosphorus oxychloride forming the 1,3,4-oxadiazolylquinoxaline ring system. Molecular modeling studies ...