Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases p. 2073 - 2084 (1982)
Update date:2022-08-03
Topics:
Barteri, Mario
Pispisa, Basilio
The oxidation by H2O2 of L-(+)-ascorbate anion in the presence of 2,2',2",2"'-tetrapyridineiron(III) complex ions anchored to poly(L-glutamate) (FeL) or poly(D-glutamate) (FeD) has been studied at pH 7.0 and varying complex-to-polymer-residue ratio .The reaction follows two parallel routes; one corresponds to an electron-transfer process within a substrate-catalyst adduct and the other refers to an uncatalysed pathway to the dehydroascorbic acid.Unusual phenomena are observed in the catalysis in the sense that only the conformational dissymmetry of the active sites, arising from the binding-induced coil-to-α-helix transition of polypeptide matrices by Fe(III) complex counter-ions, is able to impart stereospecific effects in the reaction.Evidence is produced to show that stereoselectivity is driven by activation entropy.The effect probably arises from the formation of a rather rigid precursor complex, with the optically active substrate molecules bound to the chiral residues of the ordered polymer surrounding the active sites.The stereochemistry of such an intermediate allows the reaction to proceed only by a remote electron-transfer pathway, through the quaterpyridine ligand of the metal chelate.Evidence suggests that the asymmetric
Suzhou Howsine Biological Technology Co.,Ltd(expird)
website:http://www.howsine.com
Contact:86-512-67262751
Address:No 3,Weihua Road ,Suzhou Industrial Park ,Jiangsu ,China.
Shanghai Massive Chemical Technology Co., Ltd.
website:http://www.massivechem.com/
Contact:+86 21 34943721
Address:Room 435, 4th floor, Building 9, No. 2568 Gudai Road,Minhang District, Shanghai,
Contact:+86-515-88356562
Address:No.2, West Daqing Road, Yancheng, Jiangsu, China
Shandong Zhongcheng Barium Salt Co., Ltd
Contact:+86-15725732638
Address:No.29 baoxi road, hi-tech zone, zibo, shandong
Shijiazhuang Haotian Chemical Co., Ltd.
Contact:86-311-85044374
Address:293 Donggang Road
Doi:10.1021/jo00378a015
(1987)Doi:10.1021/jo061617n
(2006)Doi:10.1016/j.tetlet.2021.153295
(2021)Doi:10.1016/S0040-4020(01)86833-2
(1987)Doi:10.1016/S0040-4039(00)96395-0
(1987)Doi:10.1002/ejoc.201901755
(2020)
