Nitrenium ions from hydroxylamine derivatives. A comparison of the transition state for heterolytic cleavage of the N–O versus C–O bond
Abstract
A ρ-value of + 0·68 has been determined for the methanolysis of a series of piperidin-1-yl benzoates, in comparison with value of ca.+ 1·35 for ρ determined for methanolysis of a series of 1-phenylcyclohexyl benzoates, indicating that the transition state for heterolytic cleavage of an N–O bond to generate a nitrenium ion occurs earlier in the bond breaking process than for heterolytic cleavage of a C–O bond to produce a tertiary carbonium ion.