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A simple and efficient methodology for the tetrahydropyranylation of alcohols using catalytic amount of copper(II)chloride in dichloromethane is described. The yields obtained are good to excellent.

A simple methodology for the debenzylation of ortho substituted phenol ethers in two phase system with aqueous hydrobromic acid in the presence of tetrabutylammonium bromide as a phase transfer catalyst is described.

A novel tea bag methodology for resolution of methyl esters of N-acetyl-α-amino acids in reverse micellar medium of bis (2-ethylhexyl) sulfosuccinate sodium salt (AOT) in isooctane-chloroform using immobilized enzymes or microbial cells is presented. The methodology effectively solves the problems of substrate solubility, product separation and surfactant recycling and provides products in high yields (80 to 90%) and excellent optical purities (% ee 97 to >99%).

The reaction of different mercapto substituted heterocycles with o,o-dialkyl chlorphosphate or thiophosphates, gave the corresponding S- and N- alkylated derivatives instead of the expected phosphorylated products.

A two step facile synthesis of isoxazoles is described. The synthesis involves copper catalysed bromoform addition to an alkene (1) to afford tribromo derivative (2) which on treatment with sodiumnitrite in DMF gives the corresponding isoxazole (3).

Trialkyl acyl ammonium halides have found to be superior phase transfer catalysts. They were easy to prepare and afford the reactions to be carried out at elevated temperature, owing to their stability.

A simple and effective stereoselective synthesis of Ostopanic acid I using β-chloro vinyl ketone as a key synthon obtained from diethyl pimeliate is described.

Enantiospecificity of the reduction process and product yields in the reduction of ethyl acetoacetate and ethyl benzoylacetate by baker's yeast immobilized in calcium aliginate beads depend strongly on the pH of the medium, and under optimum conditions products with high yields (80-85%) and high optical purity (e.e. 90-99%) can be obtained.

The synthesis of the title pheromones involves solvomer-curation of an olefin and reductive carbon-carbon bond formation with α,β-unsaturated carbonyl compounds to give the key intermediates 3(a & b), which by simple conventional methods offered (1) & (2).

A probable biogenetic type synthesis of coumestans by coupling in-situ generated o-quinones by mushroom tyrosinase oxidation of catechol and 4-hydroxy coumarins is reported.

Pyridine N-Oxide reacts with arenesulfonyl azides under thermal conditions, to form tetrazolo[l,5-a]pyridine. The condensed pyridine N-Oxides also behaved similarly, giving the respective tetrazoloazines. These reaction results indicate a novel azido transfer from arenesulfonyl azides and provide an alternative route to tetrazoloazines.

Reaction of 2-aminothiazoline with aroylisothiocyanate gave 6,7-dihydrothiazolo[3,2-a]-1,3,5-triazine-4-aryl-2-thiones (5) in one step.

A novel conversion of an alkene to a higher homologue αβ-unsaturated aldehyde was achieved in three steps. The aldehydes were used for the synthesis of traumatin, a wound hormone and bombykol, the pheromone of bombyx mori.

The mechanism of the Schmidt rearrangement has been examined in the conversion of chromanones to 1,4- and 1,5-benzoxazepinones. With substituents in the 6-, 7-, or 8-position, only electronic effects prevail resulting in the exclusive formation of 1,4-benzoxazepinones. Steric effects come into play with increasing bulk of substituents in the 5-position of the chromanone. Results now presented favor more than one pathway for the products to arise. Nuclear magnetic resonance spectra have been used to distinguish between the isomeric 1,4- and 1,5-benzoxazepinones.Several new chromanones have been synthesized.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The methyl heptenoate (I) undergoes addition reaction with tribromomethane (II) in the presence of copper to give the tribromo ester (III).

Enzymatic oxidation of catechol (II) generates o‐quinone in situ which reacts with the different cyclic 1,3‐diones (enol form) (I) etc. (see scheme) to give anellated furans in nearly quant.

Dimerization of the benzazoles (I), yielding the bis(benzazoles) (II), is promoted by dichlorocarbene which is generated from chloroform or sodium trichloroacetate in refluxing dioxane.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Reaction of the benzothiazole (I) with dichlorocarbene (generated from chloroform (II)) under phase‐transfer conditions yields the product (IV) which is presumably formed by reaction with the catalyst (III).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

With already studied electron transfer (ET) reactions from Ph‐Se‐Se‐Ph (IVb) to the excited singlet of acceptor 1,4‐dicyanonaphthalene (cat.) in mind, further ET reactions of organo‐selenium compounds are studied.

The N‐(trimethylsilylmethyl)alkenylamines (I) undergo ring‐closure upon photolysis in the presence of dicyanoanthracene to give the cyclic amines (II) or (IV) and (V).

Reaction of the oxazolones (I) with diphenyldiazomethane (II) results in cyclopropanation, forming the spiro compounds (III).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Thiophene is used as a chain extender to construct the intermediates (III).