(o-Hydroxyphenyl)methylphosphonic acids are readily obtained from o-(bromomethyl)- or o-(hydroxymethyl)phenols and trialkyl phosphites. Subsequent hydrolysis leads to the corresponding phosphonic acids. For a series of such compounds, the pKavalues have been determined by potentiometry. Their dependence on additional substituents in the aromatic ring is discussed in terms of electronic and steric
从邻-(溴甲基)-或邻-(羟甲基)酚和亚磷酸三烷基酯容易获得(邻-羟基苯基)甲基膦酸。随后的水解产生相应的膦酸。对于一系列此类化合物,p K a值已通过电位计确定。根据电子和空间效应,讨论了它们对芳环中其他取代基的依赖性。
Synthesis, structure and magnetic properties of [Cu<sub>4</sub>(Hmbpp)<sub>2</sub>(H<sub>2</sub>NC(O)NH<sub>2</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>8</sub>]·4H<sub>2</sub>O
作者:Andrew Harrison、David K. Henderson、Paul A. Lovatt、Andrew Parkin、Peter A. Tasker、Richard E. P. Winpenny
DOI:10.1039/b309475h
日期:——
[Cu4(Hmbpp)2(H2NC(O)NH2)2(H2O)8]·4H2O 1, the first example of a discrete polynuclear copper phosphonate complex isolated from aqueous media was synthesised by the addition of urea to a solution of a copper(II) salt and the bisphosphonic acid ligand 4-methyl-2,6-bis(phosphonomethyl)phenol (H5mbpp). 1 contains four distorted square pyramidal copper atoms and the Cu4 units are linked by a complicated hydrogen bonded network involving co-crystallised water molecules.