34128-01-3Relevant articles and documents
Lanthanide(III)-catalysed addition of glycolate to maleate. Investigation of intermediates using multinuclear magnetic resonance spectroscopy
Van Westrenen, Jeroen,Peters, Joop A.,Kieboom, Antonius P. G.,Van Bekkum, Herman
, p. 2723 - 2728 (2007/10/02)
The lanthanum(III)-catalysed addition of glycolate to maleate to yield carboxymethoxysuccinate(3-) (cmos) is described. It is shown that the reaction only proceeds above pH 6, indicating the formation of di-ionised glycolate as a pre-equilibrium for the rate-limiting step, i.e. the addition of the CH2-O- to the olefinic bond. Due to strong complexation of LaIII by the product cmos, the reaction requires one LaIII ion per two cmos formed. The inhibitory effects of non-reacting strong chelators such as ethylenediaminetetra-acetate, nitrilotriacetate, and 2,6-pyridinedicarboxylate indicate the formation of mixed-ligand complexes leading to the addition reaction. This has been confirmed by GdIII-induced 13C relaxation rate enhancements, and DyIII-induced 17O shift measurements.
