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.
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