Dirhodium catalyzed reactions of aryl-substituted tetrahydropyranone diazoacetoacetates produce ylide intermediates that unexpectedly yield two oxabicyclo[4.2.1]-nonane diastereoisomers, but a single diastereoisomer is formed by increasing the steric bulk of the aryl substituent.

A new total synthesis of the alkaloid variolin B is achieved by a selective and sequential palladium-mediated functionalization of a trihalo-substituted pyrido[30,20:4,5]pyrrolo[1,2-c]pyrimidine. This intermediate is obtained by a new heterocyclization reaction between an appropriate bromomethyl azaindole and N-tosylmethyl dichloroformimide. The methodology may be effective for the synthesis of...

A 2-diethanolamine boronyl substituted 1,3-diene has been synthesized in high yield and characterized spectroscopically as well as by X-ray crystallography. This diene has then subsequently been used in a number of fast, high yielding Diels-Alder/cross coupling reactions.

A strategy for synthesizing highly functionalized cyclohepta[b]indoles through a concise (4 + 3) cycloaddition-cyclization-elimination sequence is described. The cycloaddition features nitrogen-stabilized oxyallyl cations derived from epoxidations of N-aryl-N-sulfonyl-substituted allenamides, while the cyclization and elimination employed an intramolecular Grignard addition and a one-step Chuga...

indandione 1 was brominated to yield 2-bromoindandione 2 which on further reacted with substituted thiocarbamides, carbamides, 2-aminothiophenols, 2-aminophenol and triazoles to furnished 3-substituted aniline-2-thia-4-aza-6,7-benzo-8-oxo-bicyclo [3.3.0]-1(5),3-octadiene 3, 3-substituted aniline-2-oxa-4-aza-6,7-benzo-8-oxo-bicyclo [3.3.0]-1(5),3-octadiene 4, 2-thia-5-aza-9-oxo-3,4-(3’-substitut...

Indandione 1 was brominated to yield 2-bromoIndandione 2 which on further reacted with substituted thiocarbamides, carbamides, 2-aminothiophenols, 2-aminophenol and triazoles to furnished 3-substituted aniline-2-thia-4-aza-6,7-benzo-8-oxo-bicyclo [3.3.0]-1(5),3-octadiene 3, 3-substituted aniline-2-oxa-4-aza-6,7-benzo-8-oxo-bicyclo [3.3.0]-1(5),3-octadiene 4, 2-Thia-5-aza-9-oxo-3,4-(3’-substitut...

the degree of aromaticity of mono-substituted derivatives of benzene has beeninvestigated using a new index based on electric field gradient index, by using two mechanicalquantum methods with gaussian 03. two different basis sets have applied to study and theresults compared. this strategy has demonstrated that, due to violation of symmetry in have pisystems,how the degree of aromaticity can ha...

stability of the π-π stacking interactions in the ben||substituted-coronene and hfben||substituted-coronene complexes was studied using the computational quantum chemistry methods (where ben and hfben are benzene and hexaflourobenzene, || denotes π-π stacking interaction, substituted-coronene is coronene molecule which substituted with four x groups, and x= nh2, ch3, oh, h, f, cf3, cn and no). ...

Stability of the π-π stacking interactions in the Ben||N-substituted-coronene complexes was studied using the computational quantum chemistry methods (where Ben is benzene and || denotes π-π stacking interaction, and N-substituted-coronene is coronene molecule which substituted with different number of N atoms). The results reveal simultaneous effects of structure and number of Heteroatom on th...

nano tio2 supported on sio2 (nano tio2@sio2) as a solid lewis acid, was described to be an effective and reusable catalyst for one-pot three-component reaction of benzil, aryl aldehydes and ammonium acetate for the synthesis 2-aryl-4,5-diphenyl-1h-imdazoles synthesis. to explore the high efficacy of the catalytic system the four-component cyclization of benzil, aryl aldehydes, ammonium acetate ...