Kewords: Diphenyl methane, Diketone, Hydrazide, Pyrazole, Solvent free.
H2SO4 catalyzed facile synthesis of fourteen new 1-acyl-4-benzhydryl substituted pyrazoles from diketone and acyl hydrazides under solvent free conditions.
The FeCl36H2O-catalyzed benzylation of acetylacetone (1) with diphenyl methanol (2), following the reported procedure , afforded diketone (3) in very good yield (Scheme-1).
The reaction comprises nucleophilic addition of amino groups of acylhydrazides (4a-4n) to carbonyl groups of diketone (3) followed by removal of water molecules.
Morgan's findings provide strong evidence that inhaled diketone vapors can produce airway fibrotic disease and support a causal relationship between workplace exposure to high concentrations of diketones and the development of bronchiolitis obliterans, according to John Morris, a professor of pharmacology and toxicology at the University of Connecticut, Storrs.
Caption: Engineering controls such as ventilated mixing vessels with hinged lids or access ports are the first line of protection against worker exposures to diketones in flavorings.
The vicinal diketones (VDKs), diacetyl and pentanedione, are secondary by-products of the biosynthetic pathway for valine and isoleucine, respectively.
Influence of Wort Amino Acid Levels on Vicinal Diketone Production in Lager Fermentations
This can be associated with modifications in the chemical environment of the carbonyl bonds and also to a possible formation of [Beta] enolized diketone
It was inferred that the substituted [beta]-diketone underwent photolysis during exposure and the diketone structure was broken down.
Content of Molar ratio Reaction Content of diketone MA Acrylate (acrylate/ time acryloyloxy structure oligomer monomer acac) (min) group (mol/g) (mol/g) TMDAC TMPTA 2:1 50 4.