Cyclization of 2-(3-halopropyloxy)phenoxide ions in functionalized surfactants

Article abstract of DOI:10.1016/0040-4020(95)00587-X

Observed rate constants (k(obs)) of cyclization of 2-(3-halopropyloxy)phenoxide (halo = bromo, iodo; PhBr7 and PhI7, respectively) in aqueous micelles of N-hexadecyl-N-(2-hydroxyethyl)-N,N-dimethylammonium bromide (1) depend on [1] and [NaOH]. The rate profiles go through a maximum and, at high [1], the catalytic effect is modest. By contrast, k(obs) in aqueous micelles of N-hexadecyl-N-(2-hydroxyethyl)-N,N-dimethylammonium sulfate (2) increases monotonically with increasing surfactant concentration and becomes constant at high [2]. ¹H, ¹³C, and ¹⁴N NMR spectra of 1 and 2 show that micelles of 1 and 2 do not differ in dimension and shape and that the average conformations of 1 and 2 are similar.