Bulletin of the Chemical Society of Japan p. 1003 - 1007 (1997)
Update date:2022-08-16
Topics:
Nishikawa, Sadakatsu
The ultrasonic absorption coefficients over frequency range from 1.0 to 220 MHz were measured in aqueous β-cyclodextrin solutions with 1-butanol and 2-methyl-2-propanol at 25 °C. A clear single relaxational absorption with a relaxation frequency from 5 to 20 MHz was observed in a solution with 1-butanol, while the relaxational absorption was found in a lower frequency range in a solution with 2-methyl-2-propanol. The cause of the relaxation was attributed to a perturbation of a chemical equilibrium associated with complexation between β-cyclodextrin (host) and alcohol (guest). The rate and equilibrium constants for the complexation were determined from the concentration dependence of the relaxation frequency for the solution with 1-butanol. The standard volume change of the reaction was also obtained from the maximum absorption per wavelength. These results were compared with those for complexation between β-cyclodextrin and 1-propanol, and were considered in relation to the alcohol molecular structure. It was found that the rate of complex formation is almost independent of the guest molecule, and, therefore, the equilibrium constant for the complexation is controlled by the rate of departure of the guest molecule from the host. From this fact, the rate parameters for a solution with 2-methyl-2-propanol were estimated, and the calculated ultrasonic relaxation parameter was compared with the experimental data.
View MoreShanghai Yuking Water Soluble Material Tech Co., Ltd
Contact:86-21-68286299
Address:4F, 13B, No. 600, South Xinyuan Road 201306, Shanghai, China
Shandong Dayi Chemical Co., Ltd.
website:http://www.dayi.com.cn
Contact:+86- 535-7388728. 15306386031
Address:No 1 Danya west road, Laiyang City, Shandong province
Jinan Kaypharm Chemical Co.,Ltd
Contact:86-0531-86986780
Address:Room101,No189-2,Huayuan Road,Jinan City,Shandong Province
Contact:0086-29-89196322
Address:North of the Fifth Keji Road, Hi-Tech Industrial Zone, Xi'an City, Shaanxi Province, China
Shanghai Hanhong Scientific Co.,Ltd.
website:http://www.chemvia.com
Contact:+86-21-64541543,54280654,13918533501
Address:Jiachuan Road 245
Doi:10.1055/s-1997-715
(1997)Doi:10.1007/BF00918614
()Doi:10.1016/0009-2614(95)00501-T
(1995)Doi:10.1021/ic5020972
(2015)Doi:10.1016/j.tca.2011.05.004
(2011)Doi:10.1016/j.ica.2018.11.009
(2019)