A convenient method for the preparation of nitro olefins by nitration of olefins with nitrogen monoxide

Olefins with a terminal double bond or conjugated with aromatic nucleus are successfully nitrated into nitro olefins in good-to-high yields on treatment with nitrogen monoxide (NO) in 1,2-dichloroethane. Nitro alcohols formed as by-products are dehydrated to yield nitro olefins by the subsequent treatment with acidic activated alumina. By GC analysis, it was confirmed that an equimolar amount of nitrogen gas was evolved during the present nitration. A possible reaction pathway including the formation of nitro nitroso compounds, key intermediates, is described. The key intermediates are transformed into nitro olefins by reaction with nitrogen monoxide.