Rate studies of the acid-catalyzed solvolysis of eight-membered cyclosilazoxanes

Article abstract of DOI:10.1016/0022-328X(91)80098-5

The solvolysis of N-phenyl-1,1,3,3,5,5,7,7-octamethyl-1,3,5,7-tetrasila-2-aza-4,6,8-trioxacyclooctane (1) and N,N'-diphenyl-1,1,3,3,5,5,7,7-octamethyl-1,3,5,7-tetrasila-2,6-diaza-4,8-dioxacyclooctane (II) in methanol/water in the presence of an acetate buffer is a pseudo-first-order process, subject to general acid-catalysis.The catalytic rate constants have been determined spectrophotometrically for the solvolysis of I.The ring cleavage is slower than that of analogous six-membered cyclosilazoxanes, but the catalytic mode and the solvent isotope effect indicate a close mechanistic similarity between the solvolyses of six- and eight-membered rings.