alumina is found to promote the conjugate addition of indoles to nitroalkenes in solventlessconditions at 60 °C. Nitroalkenes can be replaced by nitro alcohols that are converted into nitroolefins under the reaction conditions. Alternatively, a tandem nitroaldol-dehydration allows the utilization of nitroalkanes and aldehydes as remote precursors of reactive nitroalkenes in a ‘one–pot’ synthesis of 3-substituted