Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases p. 3223 - 3232 (1988)
Update date:2022-09-26
Topics:
Pedersen, Jens A.
Electron spin resonance spectra have been obtained from series of 2-substituted anthrasemiquinones and of 3-substituted 1,8-dihydroxyanthrasemiquinones.The proton splittings are consistently assigned by means of linear correlation plots between splitting constants and a substituent-dependent paramater.All lines in the plots of he two series of compounds obey the following linear equation aRi = AixR + aHi where aHi and aRi are the splitting constants at position i before and after the substituent has been added.Ai is the slope of the line for the splittings from position i and xR is a constant characteristic of the substituent R. xR is comparable to the Hammett ? parameter.Electron-donating substituents at C-2 are shown to increase the spin densities at the positions 1 > 6 > 8, and to decrease them at the positions 4 > 3 > 7 > 5, with the strength of the effect indicated.Electron-withdrawing substituents have the opposite effect.Preliminary Hueckel molecular-orbital calculations qualitatively predict the observed correlations, solely by changing the parameter for the resonance integral.
View MoreGlobal United Biotechnology Inc.
Contact:+86-21-61618568
Address:Room 309, Building 6, NO.135, Jinyu Road, Pudong
website:https://www.synose.com/
Contact:86-579-82275537
Address:No.1958 Liyu Road , jinhua,zhejiang,China
Shanghai Balmxy Pharmaceutical Co., Ltd
Contact:0086-21-24206007
Address:Room 402, 15#, No. 909 wangyue Road, shanghai, P. R. China
Contact:
Address:308# dongwu avenue dongxihu district wuhan city
Chuzhou Baiao Biologhy S&T Co., Ltd.
Contact:+86-25-83212599；+86-25-83212699 13705185959
Address:Room 905, Tianzheng International Platza, No.399, Zhongyang Road ,Nanjing, Jiangsu Province, China
Doi:10.1016/S0040-4039(02)02839-3
(2003)Doi:10.1021/jo9908501
(1999)Doi:10.1359/jbmr.2001.16.5.876
(1906)Doi:10.1039/jr9300002685
(1930)Doi:10.1016/S0045-2068(03)00040-3
(2003)Doi:10.1016/j.bmcl.2014.06.064
(2014)
