Abstract The rates of solvolysis of some N-phenyl-1-aza-3, 5-dioxa-2, 4, 6-tris (dimethylsily) cyclohexanes, substituted in the benzene ring, have been measured spectrophotometrically in methanol containing a small quantity of water. The reaction is subject to general acid catalysis and is inhibited by weak bases. Electron-donating substituents accelerate the solvolysis. The ϱ-constant, derived from the linear relation between the logarithms of the ...