Absorptance spectrum methanol production from

The electronic absorption spectrum of the cation-radical of thiophene itself has been observed following low-temperature y-radiolysis of the heterocycle in a Freon matrix.The radical has also been implicated in the oxidation of thiophene by dibenzoyl peroxide it is believed to be formed at the contact of certain transition metal layer-silicates with thiophene.The anodic oxidation of 2,5-dimethylthiophene has been studied by Japanese workers who found strong evidence for the formation of the cation-radical as the primary oxidation product.In the presence of strong nucleophiles such as cyanide ion, the cation-radical undergoes nucleophilic attack before further oxidation. In the presence of more basic species such as acetate ion, the cation-radical is deprotonated to give a thienylmethyl radical which undergoes further reaction. The results were compared with similar observations for the oxidation of 2,5-dimethylfuran. Czech workers have also studied the anodic oxidation of substituted thiophenes. This work has focused on the preparative value of anodic oxidations in acidified methanol. Cation-radical formation is implied for the primary step, but the value of the method lies in the fact that sulfur is ultimately eliminated from the substrate and functionalized y-dicarbonyl compounds result. 

Once laid, the polystyrene films were further purified by exhaustive extraction with methanol or n-heptane the progress of extraction was followed by the ultraviolet spectra of the extracts. These preirradiation extractions showed considerable variation in purity among the three polystyrenes in spite of reprecipitation measures. The degree to which solvents can remain with a 20/ film is suggested by the need of seven days of continuous methanol or n-heptane extraction to remove all of the extractable benzene from a film laid from that solvent and dried in vacuum at 65°C. for 24 hours. For film laid from methylene chloride, an optically clean n-heptane extract was obtained from the AIBN-ini-tiated sample within a few hours, but up to 48 hours were required for the benzoyl peroxide-initiated samples. The extracted 20/ polystyrene films were essentially non-absorbing above 285 m/, no absorption attributable to material other than polystyrene could be observed, and only one peak (337 m/ ) was seen in the fluorescence spectrum in methylene chloride. Once the films were purified by extraction, the products and wettability changes resulting from irradiation were the same for all polystyrene samples and were independent of the solvent from which the films were laid. 

Support for the partial structure C comes from the reduction of caracurine II with zinc and concentrated sulfuric acid in methanol, which affords a diol (XCIX) showing strong hydroxyl absorption in the IR -spectrum. The basic strength of the Na nitrogen atoms in this product... 

An anhydride reacts with an alcohol to produce an ester and a carboxylic acid. So when succinic anhydride is heated in methanol it produces the monomethyl ester of succinic acid. This Is apparent from the presence of an OH band and two carbonyl bands in the IR spectrum and the signal at 10.25 5 in the NMR spectrum of the product. However, in the presence of a catalytic amount of sulfuric acid, the carboxylic acid group of the initial product reacts with methanol to form a diester. This is consistent with the IR spectrum of this product and the fact that it shows only three absorptions in its C-NMR spectrum. 

Isolation and full characterization of each component of EL-499 has been elusive. However, isomer pure (1) was prepared by several methods including fractional recrystallization. (8) Cyclohexyl isomer enrichment was also achieved with EL-499 by selective hydrolysis. When EL-499 was refluxed in aqueous methanol with triethylamine for 16 hours, the appearance of 2-bromo-4-nitroaniline was observed by thin layer chromatography. Isolation of the carboxanilide products as a single band from column chromatography gave >99% (1) as evidenced from its FI9 NMR spectrum (Figure 3), which exhibited no detectable trifluoromethyl absorption and indicated that under these conditions the carboxanilides (2) were more reactive than (1). ... 

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