Tandem 6π-Electrocyclization and Cycloaddition of Nitrodienes to Yield Multicyclic Nitroso Acetals
作者:Gardner S. Creech、Ohyun Kwon
DOI:10.1021/ja1038819
日期:2010.7.7
6pi-electrocyclization to form nitronate intermediates, which can be captured through tandem [3 + 2] dipolar cycloadditions to form highly functionalized nitroso acetals. The one-pot, two-step domino process is highly efficient, proceeding with good facial selectivity and exoselectivity. Dipolarophiles featuring electron-rich, -neutral, and -deficient carbon-carbon double bonds are viable substrates
Synthesis of nitrodienes, nitrostyrenes, and nitrobiaryls through palladium-catalyzed couplings of β-nitrovinyl and o-nitroaryl thioethers
作者:Gardner S. Creech、Ohyun Kwon
DOI:10.1039/c3sc50773d
日期:——
A highly efficient, base-free, mild protocol for the palladium-catalyzed, copper-activated desulfitative couplings of vinyl and aryl β-nitrothioethers generates a wide variety of conjugated nitroorganics. Orthogonality to traditional SuzukiâMiyaura coupling is demonstrated, as well as synthetic utility, through reductive Cadogan cyclization, for the formation of indoles, carbazoles, and pyrroles.
Highly stereoselective preparation of nitro olefins and nitro dienes by the addition-elimination of copper-zinc organometallics to β-alkylthio and β-phenylsulfonyl nitro olefins
作者:Carole Retherford、Paul Knochel
DOI:10.1016/s0040-4039(00)79462-7
日期:1991.1
onyl ethylene 2a gave highly functionalized pure (E) nitroolefins and stereoselectively (1E, 3E) and (1E, 3Z)-1-nitrodienes in excellent yields. β-Alkylthio nitroolefins such as 2-ethylthio-1-nitro-1-cyclohexene 2b and 2,2-dimethylthio-1-nitroethylene 12 were found to have a similar behavior. This methodology allowed an expeditive preparation of the triene 5 which underwent an extremely mild silica
Lewis acid mediated thienium cation diels-alder reaction: A new method for regio- and stereoselective functionalization of 1,3-dienes
作者:Kaoru Fuji、Subhash P. Khanapure、Manabu Node、Takeo Kawabata、Akichika Ito
DOI:10.1016/s0040-4039(00)89135-2
日期:1985.1
aluminum chloride the β-ethylthionitroolefin results in the formation of the thienium cation, which reacts with a variety of 1,3-dienes in the Diels-Alder sense. The cleavage of the resulting ring provides in one pot the 1,4-functionalized olefins in regio- and stereoselective manner.
Preparation of polyfunctional nitro olefins and nitroalkanes using the copper-zinc reagents RCu(CN)ZnI
作者:Carole Jubert、Paul Knochel
DOI:10.1021/jo00046a027
日期:1992.9
The addition of the copper-zinc reagents RCu(CN)ZnX to a variety of nitro olefins produces polyfunctional nitroalkanes in high yields. The intermediate zinc or copper nitronates can be directly submitted to a Nef reaction (O3,-78-degrees-C) and converted to polyfunctional ketones in a one-pot procedure. The addition of RCu(CN)ZnX to nitro olefins bearing a leaving group (RSO2, RS) in the beta-position provides pure (E)-nitro olefins in excellent yields. The reaction has been applied for the stereoselective preparation of 1,3-nitrodienes and for a Diels-Alder reaction precursor.