Journal of the Chemical Society. Perkin transactions II p. 73 - 78 (1990)
Update date:2022-08-11
Topics:
Goto, Ayako
Kishimoto, Hiroshi
The bimolecular reaction of cyanide (CN-) ion with N-methyl-3-carbamoylpyridinium (S+) ion, in the water pool of the reversed-micellar system water/ hexadecyltrimethylammonium bromide (HTAB)/ chloroform-isooctane (3:2, v/v) has been studied at various temperatures (15-40 deg C) by measuring spectrophotometrically the decrease of the absorption due to S+ (265 nm) and the increase of the absorption due to the addition product (340 nm).The results of the reaction series were examined throughout with respect to the molar ratio of water to HTAB, R.Since the rate and equilibrium constants of the bimolecular reaction are affected by the method in which the concentrations of reactants are defined or by fixing the extent of reaction space, the water pool is assumed to be the sole reaction space and the rate and equilibrium constants in the water pool, k2w and Kw, which are based on the modified concentrations of the reaction species, have been evaluated.It is found that terms of k2w and Kw, the smaller the value of R, the more the addition reaction is enhanced.From the relationships between Kw and k2w vs. temperature, the standard and activation enthalpies of reaction, ΔH<*> and ΔH<*>, respectively, have been calculated.The behavior of ΔH<*> and ΔH<*> as well as Kw and k2w is found to differ in reactions which have R below and above ca.3.To explain the enhancement of the reaction due to the specific field effect of the water pool and the retardation of the reaction due to electrostatic interactions among S+ ions, the involvement of CN- and HTAB ions is proposed.The differing behaviour in the reactions is more clearly manifested in the thermodynamic and kinetic diagrams of enthalpy vs. entropy, which give separate plots corresponding to R both below and above ca.3.In addition, the effect of varying the CN- ion concentration is discussed and is found to be consistent with the situation described above.
View Moresuzhou chukai pharmateach co,.ltd
Contact:86-512-88812511
Address:Building 3, Wujiang Scientific Innovation Park, 2358 Changan Rd, Wujiang 215200, Jiangsu Province, P. R. China
Shanghai Bocimed Pharmaceutical Co., Ltd.
website:http://www.bocimed.com
Contact:+86-21-68861632
Address:Building 1, Lane 647, Songtao Road, Zhangjiang High-Tech Park, Shanghai
Contact:0833-5590788/5590338/5590055
Address:Victory in the town of Red Star Village,Mount Emei City,industrial concentration area storage processing logistics parkpark
Suzhou BEC Fine Chemicals Co., Ltd.
website:http://www.bek.com.cn
Contact:0512-68095917 18913193865
Address:6, Jin Shan Road, Suzhou New District, 215011 China Suzhou Nations Pharmaceutical Innovation Center Inside
Jinan Trio PharmaTech Co., Ltd
Contact:86-531-88811783;+(0)13153010282
Address:2766 Yingxiu Road, Jinan High-Tech Zone, China
Doi:10.1016/0040-4020(70)80030-8
(1970)Doi:10.1246/bcsj.13.482
(1938)Doi:10.1016/S0925-8388(00)01124-5
(2000)Doi:10.1016/S0022-4596(02)00081-6
(2003)Doi:10.1039/c9nj05948b
(2020)Doi:10.1055/s-1999-2994
(1999)