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Copper catalysed oxidative coupling reaction of formamides with β-keto esters and 2-carbonyl-substituted phenols successfully proceeded through direct C–H bond activation of formamides. The corresponding carbamates were formed with high stereoselectivity under mild reaction conditions. This protocol was successfully applied to the synthesis of three novel halogenated carbamates and a carbaryl insecticide derivative. Our results suggest the use of 6.0 equiv. TBHP is crucial for this type of reaction.

Polyaniline (Pani) and Polyaniline-silver nanocomposites (Pani-Ag) were prepared by employing interfacial polymerization using ammonium persulphate as an oxidizing agent. During the polymerization, the Ag+ is reduced to Ag0, and the formations of regular nanocomposite materials were studied by Fourier transform infrared spectroscopy and UV–visible spectroscopy techniques. Scanning electron microscopy and transmission electron microscopy images were conducted to characterize the morphology. Thermogravimetric and differential thermal analysis were carried out to study the thermal stability of the resulting composites. Formation of conducting emeraldine salt form was concluded by electrical conductivity. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

A diverse library of novel carbamates was synthesized utilizing copper-catalyzed oxidative C–O coupling of formamides and salicylaldehydes. Sensitive aldehyde groups remained intact in the presence of an oxidant and a transition-metal salt. Salicylaldehydes bearing electron-donating, electron-withdrawing, and halogen groups as well as 1-hydroxy-2-naphthaldehydes provided the desired carbamates in good to excellent yields.

A simple iron carbonyl catalyzed method for the α-selective aryloxylation of cyclic ethers is developed using a variety of salicylic aldehydes as phenol derivative and tBuOOH as the oxidant.

1,5-Diphenylpent-3-en-1-yne derivatives were isolated in minor quantities from terrestrial plants and exhibited strong anti-inflammatory activity. A cross coupling reaction between B -benzyl-9-BBN and chloroenynes under mild condition was developed resulting in the formation of different 1,5-diphenylpent-3-en-1-yne derivatives with a full control on the E / Z selectivity. Several substrates bearing electron-donating and electron-withdrawing substituents were tolerable under the reaction conditions affording the corresponding products in good yields. This is the first study to report the synthesis of a vast array of novel 1,5-diphenylpent-3-en-1-yne derivatives paving the way for the preparation of tailored derivatives on mass scale necessary for biological studies and drug development.

A facile, mild, and selective method for the synthesis of benzopyran derivatives is reported.

IT HAS LONG been known that Saccharomyces cerevisiae ferments galactose by an adaptive enzyme produced in the cell during the course of a few hours in the absence of cell division. Winge and Roberts (1948) have studied a culture of S. Chevalieri which ferments galactose by "long-term" adaptation which occurs after cells have grown from 3-14 days in a medium containing galactose. After the adaptation, the fermentation itself occurs at a rapid rate. They state that "long-term" adaptation of S. Chevalieri to galactose does not involve a shift in the population (mutation followed by selection) but is an adaptation of the entire original population. They consider the delay an indication of the time required by the cells to build up galactozymase to a sufficiently high concentration to make it demonstrable. They made hybrids between these two species and found a regular segregation of rapidly fermenting (1-2 days) to "long-term" adapting (3-14 days) clones from each ascus, provided the ascospores were isolated in beer wort, a medium containing considerable amounts of maltose, but lacking galactose. If the ascospores were isolated in galactose broth, all four spores from each ascus fermented galactose immediately (1-2 days). However, they used only asci in which all four spores germinated and the possibility exists that some nonutilizers of galactose may have failed to grow in maltose. They described a series of experiments in which they deadapted and readapted galactose fermenting cultures and denied the significance of mutation as a factor in this process. Extended genetical analyses bv Lindegren (1949) have established the allelism of a single pair of galactose genes (G/g) in Saccharomyces. One of these alleles (G) controls the rapid fermentation of galactose while cells carrying the other (g) do not effect detectable fermentation of galactose under the conditions of the Durham tube fermentation test. (Occasional irregularities in which an excess of fermenter (G G G g) or an excess of nonfermenter (g g g G) alleles were obtained from single asci have been interpreted as the result of conversion of alleles in the heterozygote.) We have discovered occasional cultures in our pedigrees which resemble the cultures of S. Chevalieri described by Winge and Roberts, by fermenting galactose after a long exposure involving growth; the present paper deals with the behavior of these unusual "slow" fermenters of galactose. We have concluded that this involves mutation from the g to the G allele followed by selection of the mutant G population in the presence of galactose.