Voltammetric study of the facilitated halide-ion transfer by macrotricyclic quaternary ammonium-ion across the oil-water interface

Ohnuki, H Ito, N Ichikawa, K Kataoka, M

H. Ohnuki et al., Voltammetric study of the facilitated halide-ion transfer by macrotricyclic quaternary ammonium-ion across the oil-water interface, ELECTROCH, 69(3), 2001, pp. 187-192

25

GIAPPONESE

Article

Physical Chemistry/Chemical Physics","Chemical Engineering

ELECTROCHEMISTRY

1344-3542 → ACNP

69

3

2001

187 - 192

ISI

1344-3542(200103)69:3<187:VSOTFH>2.0.ZU;2-D

The facilitated transfer of chloride./bromide ion encapsulated into macrotr icyclic quaternary ammonium ion NtMQA(4+) (Nt = - CH2C10H7) through the wat er(aq)/nitrobenzene(nb) interface was revealed using cyclic voltammetry. Th e observed anodic-peak current i(p,a) between 100 and 400 mV vs. Hg. Hg2SO4 /SO42- resulted from the transfer of NtMQA(4+) as well as Cl(-)subset of Nt MQA(4+) from (aq) to (nb) : the cathodic-peak current i(p,c) was also obser ved as a result of their transfer from (nb) to tag). However, benzyl (= Bn) derivative BnMBA(4+) showed no clear anodic peak because of its own less h ydrophobicity, compared with NtMQA(4+). The order of I(-)greater than or eq ual to Cl- >Br in the magnitude of the observed i(p,a) resulted from the or der, Cl- >Br- >I-, for i(p,a) controlled by the order, Cl <Br-<I-, for stab ility constants of the ion-pair of halide ion with NtMQA(4+) as well as fro m the order, Cl- <similar to> Br- < I-, for i(p,a) controlled by the inclus ion of each halide ion into NtMQA(4+). The plots of i(p,a) and - i(p,c) as a function of log [X-] became linear for Cl- and hyperbola for Br- between 10(-6) M and 10(-3) M X-. The chloride-ion transfer across tag) (nb) interf ace may be more selectively facilitated using an advanced NtMQA(4+), the el ectrolytic cell may be developed for its own application to efficient chlor ide-ion prove.