Bulletin of the Chemical Society of Japan p. 775 - 778 (1996)
Update date:2022-08-02
Topics:
Sakurai, Tadamitsu
Nagaoka, Tohru
Kamiya, Jun
Inoue, Hiroyasu
Substituent and temperature effects on the equilibrium constants for the triethylamine-catalyzed acyl exchange reactions of N-(substituted benzoyl)-O-acetyl-o-aminophenols have been investigated by 1HNMR spectroscopy. It was found that the standard enthalpy change ΔHo in acyl exchange processes, estimated from temperature dependence of the equilibrium constant, correlates well with the standard free energy change ΔGo which was used as a measure of the relative stability of isomer pairs, while the standard entropy change ΔSo is approximately constant (-6±2 J K-1 mol-1) irrespective of the substituems in benzoyl introduced. The finding of enthalpy-controlled acyl exchange reactions confirms that the relative stability of a given isomer pair is determined by the difference in electrostatic force of attraction between the amide nitrogen with a partial positive charge and the ester carbonyl oxygen having a partial negative charge in both isomers.
View MoreSynochem Ingredients Corp., Ltd.
Contact:+86-512-5636 2180
Address:Zhangjiagang Free Trade Zone
SHANGHAI ARCADIA BIOTECHNOLOGY LTD.
Contact:+86-21-61353236
Address:SUITE 901, BUILDING WENSLI, 1378 LU JIA BANG RD, SHANGAHI 200011, P.R.CHINA
Wuhan Yitongtai Science and Technology Co.,Ltd.
Contact:+86-27-88933550
Address:27th Fl. Bldg. 1, Shuian International Mansion, Heping Ave, Wuhan, Hubei, China
Suzhou Sibian Chemical Technology Co., Ltd
website:http://www.sibianpharm.com
Contact:+8618169181984,+8618013186906
Address:Room1404,BuildingA,Jiabao Square No.323 Baodai East Road,Wuzhong District,Suzhou Jiangsu China (215128)
Shanghai united Scientific Co.,Ltd.
Contact:+86-21-53535353
Address:28F No.900 huaihai Road Shanghai China
Doi:10.1016/S0040-4039(00)97572-5
(1990)Doi:10.1021/ol0352862
(2003)Doi:10.1002/jhet.5570140605
(1977)Doi:10.1016/j.bmcl.2004.12.071
(2005)Doi:10.3390/molecules19078725
(2014)Doi:10.1021/jo00427a028
(1977)