Molecular and supramolecular features of oxo-peroxovanadium complexes containing O3N, O2N2 and ON3 donor sets

The complexes VO(O2)Hbpa]+ (1a), VO(O2)bpa] (1b, Hbpa = bis(picolyl)-beta-alanine), VO(O2)heida]- (2, H2heida =N-(2-hydroxyethyl)iminodiacetic acid), VO(O2)(3OH-pic)2]- (3a), VO(O2)(3OH-pic)2]-/V(O2)2(3OH-pic)2]- (3b, 3OH-pic = 3-hydroxypicolinic acid), VO(O2)(3OH-pa)2] (6, 3OH-pa = 3-hydroxypicolylamide), VO2(3OH-pic)2]- (4), VO(tBuO2)(3OH-pic)2] (5) and VO(tBuO2)(3OH-pa)2]2+ (7) have been characterised. The structures of 21aClO4].1b.2.25H2O, K.2H2O, NH4].H2O and nBu4]3b are reported. Supramolecular patterns arise from intermolecular hydrogen bonds, the relevance of which for the peroxo/hydroperoxo intermediates in oxo transfer reactions catalysed by vanadate-dependent haloperoxidases is addressed. Specific solution patterns have been analysed by 51V and 17O NMR.