The copper-catalyzed conjugate addition-cycloacylation reaction of zinc homoenolatee with acetylenic esters or acetylenic amides is described. The zinc homoenolate is prepared from [ (ethoxycyclopropy1)oxyltrimethylsilane and zinc chloride in ether. Addition of an acetylenic amide or ester provides 2-carboxamidoor 2-carboalkoxy-3-alkylcyclopent-2-en-l-ones ingood to excellent yields. The reacti...

Depending on the substitution pattern and the solvent, the gold-catalyzed cyclization of alk-4-yn-1-ones affords different oxygen heterocycles under mild reaction conditions. Alkynones with one substituent at C-3 undergo a 5-exo-dig cycloisomerization to substituted furans , whereas a 6-endo-dig cyclization to 4H-pyrans is observed with substrates bearing two substituents at C-3. In alcoholic s...

The unique flavor of peanuts that develops during roasting is the primary driving force for consumption peanut products. Although rarely consumed raw, raw state contains precursors involved in transformations lead to distinct development roasted peanuts. Volatile compounds extracted from headspace above and samples runner virginia market types by solid phase microextraction were characterized u...

Cava is a sparkling wine produced using traditional method that must be aged in contact with lees for minimum period of nine months. The between and improves the quality final product, aroma one most important qualitative parameters wine. aim work was to study role ageing Spanish (Cava), by sampling at industrial scale bottles, from 9 30 months ageing, jointly winery real time. volatile profile...

An assisted tandem catalytic transformation of diallyl amines and diallyl ethers into N-aryl pyrroles and furans, respectively, is described. The sequence relies on ring closing metathesis followed by dehydrogenation of the initially formed dihydropyrroles and dihydrofurans. Both steps are Ru-catalyzed, but the sequence requires only one precatalyst, because conversion of the metathesis catalys...

Disposal of plastic waste is a serious concern in India. New technologies have been developed to minimize their adverse effect on the environment. Currently worldwide accepted technology used for the plastic disposal is incineration.However, the incinerators designed poorly, releases extremely toxic compounds (chlorinated dioxins and furans) therefore, facing strong opposition from various non-...

The selective construction of a diverse array of five-membered aromatic heterocycles from common starting materials is an attractive and challenging task. We report here that 5-alkylthio-pyrroles, 4-alkylthiocarbonyl-pyrroles and 2-alkylthio-4-tosyl-furans can be prepared, selectively, in a single operation using the readily available α-formyl ketene dithioacetals as common precursors, through ...

Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational expo...