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 catalysts or...

Abstract. Carbonyls are among the most abundant volatile organic compounds in atmosphere. They central to atmospheric photochemistry as absorption of near-UV radiation by C=O chromophore can lead photolysis. If photolysis does not occur on electronic excited states, non-radiative relaxation ground state will form carbonyls with extremely high internal energy. These “hot” molecules access a rang...

This study has used proton transfer reaction-mass spectrometry (PTR-MS) for direct air analyses of volatile products resulting from the reactions of ozone with human skin lipids. An initial series of small-scale in vitro and in vivo experiments were followed by experiments conducted with human subjects in a simulated office. The latter were conducted using realistic ozone mixing ratios (approxi...

Co2(CO)8 has proved a key material for the preparation of a variety of cobalt carbonyl com­ plexes. Although most of its reactions involve oxi­ dation, reduction, disproportionation or substitu­ tion [2], addition reactions are scarce. Moreover, Co2(CO)8 is one of the few compounds to form ad­ dition products with strong Lewis acids such as AlBr3 [3]. The acid adds to the oxygen atom of a bridg...

A novel approach to the synthesis of pyrazole derivatives from tosylhydrazones of alpha,beta-unsaturated carbonyl compounds possessing a beta-hydrogen is proposed, exploiting microwave (MW) activation coupled with solvent free reaction conditions. The cycloaddition was studied on three ketones (trans-4-phenyl-3-buten-2-one, beta-ionone and trans-chalcone). The corresponding 3,5-disubstituted-1H...

The compound chalcone is very common which can available by synthetic means and naturally occurring from plant sources. These compounds have predominant value for their abundant properties with less adverse impacts on biological systems. belongs to the flavonoid family. Chalcones are structural two aromatic rings connected three carbon ? & unsaturated carbonyl They possess many pharmacologi...

This review is devoted to relatively new and promising approach the synthesis of novel organic compounds polymer materials, based on “click chemistry” concept. Several types reactions” (cycloaddition, nucleophilic ring opening, non-aldol carbonyl chemistry, addition multiple carbon-carbon bonds) have been described, relevant examples provided. The “thiol-ene” reactions thiol unsaturated functio...

A sensitive liquid chromatograph/tandem mass spectrometric technique (LC/MS/MS) was applied to determine aliphatic and aromatic carbonyl compounds in ambient air. Traces of the carbonyl compounds were sampled by passing through a Sep-Pak DNPH-silica cartridge. Their derivatives were thus eluted with acetonitrile, separated by reversed-phase liquid chromatography and determined by quadrupole tan...

In the title compound, C(21)H(30)N(2)O(5)S, the plane of the dimeth-yl-thio-carbamic group makes a dihedral angle of 78.41 (7)° with the central benzene ring. One of the carbonyl groups in the α,β-unsaturated malonate side chain makes a dihedral angle of 8.73 (10)° with the central benzene ring, while the other carbonyl group makes a dihedral angle of 81.52 (8)°.