Rate constants for the Michael addition of CN-in water, aqueous sulfolane, and DMSO, and MeO-in MeOH to eight mono-and disubstituted 1, 1-diaryl-2, 2-dinitroethylenes were measured. The ρ values are in the range 0.7 (CN-/H2O)-1.6 (MeO-/MeOH). For each of the