(2) with a slope of unity over a wide range (108 in reactivity) of substituents from p-MeO to unsubstituted derivatives. The substituent effect on the solvolysis of 1 should be closer to that on the solvolysis of 2, rather than to the σ+ substituent effect. The ρ value for this system was estimated to be identical to the value of −6.3 assigned for 2, and the r value in the LArSR correlation to be comparable