Journal of the American Chemical Society p. 12070 - 12077 (1995)
Update date:2022-08-05
Topics:
Bruice, Thomas C.
Blaskó, Andrei
Arasasingham, Ramesh D.
Kim, Jang-Seob
The phosphodiesters of 4,4′-methylenebis(3-hydroxy-2-naphthoic acid) (4) and 3-carboxy-2,2′-dihydroxydiphenylmethane (5) are constrained into a cyclic structure such that the oxygens of the two o-carboxy groups of 4 and the single o-carboxy group of 5 have restricted stereospecific positions with an o-CO2- oxygen to phosphorus distance of 3.7 ?. In the hydrolysis of 4, 31P NMR and HPLC data show the existence of an intermediate cyclic acyl phosphate in the g,g conformation. The 18O isotopic effects on 31P chemical shifts show incorporation of two 18O atoms in the product H3PO4. This observation is consistent with intramolecular o-CO2- nucleophilic attack on phosphorus to provide an acyl phosphate intermediate which undergoes hydrolytic cleavage by HO-/H18O- attack on phosphorus {one 18O incorporation} to provide a phosphate monoester which also undergoes hydrolysis with a second 18O incorporation on phosphorus. For hydrolysis of 4, the pH vs log kobsd profile, the values of the deuterium solvent kinetic isotope effect, and the activation entropy accord a mechanism which involves intramolecular attack of o-CO2- on the phosphate phosphorus assisted by the o-CO2H as a general acid catalyst. The latter can involve o-CO2H hydrogen bonding to the -(PO2-)- oxygen(s) and/or leaving phenolic oxygen. At neutrality, 4 hydrolyzes ca. 104 fold faster than 5 which only has one o-carboxy group and 108-109-fold faster than diphenyl phosphate.
View MoreWeifang Arylchem Chemical Co., LTD
Contact:86-536-5217866
Address:Development Zone, Shouguang, Shandong Province
Tianjin Chemsyntech Chemical Co., Ltd
Contact:+86-22-60872258
Address:Haitai green industry base in Tianjin, K1,5-601
Yancheng Creator Chemical Co., Ltd
Contact:0086-515-88710008 88710068 88710858 88710868
Address:No.21 Renming Road, Longgang Town, Yandu County,Yancheng City
Shanghai Standard Biotech Co., Ltd.
Contact:+86-18502101150
Address:Room 103, Building 2nd, NO.720, Cailun Road , Pudong District, Shanghai, China
Chengda Pharmaceuticals Co., Ltd.
Contact:+86-573-84601188
Address:hengshan Road 5# in Jiashan, zhejiang
Doi:10.1016/S0960-894X(02)01004-1
(2003)Doi:10.1021/ja01505a044
(1960)Doi:10.1139/v75-016
(1975)Doi:10.1016/j.jorganchem.2020.121177
(2020)Doi:10.1021/bi00679a028
(1975)Doi:10.1021/jo01161a015
(1948)