Can-Yu Chen1, Mao-Long Chen2, Hong-Bin Chen2, Hongxin Wang3, Stephen P Cramer4, Zhao-Hui Zhou5. 1. State Key Laboratory for Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China. 2. State Key Laboratory for Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. 3. Department of Chemistry, University of California, Davis, CA 95616, United States. 4. Department of Chemistry, University of California, Davis, CA 95616, United States. Electronic address: spjcramer@ucdavis.edu. 5. State Key Laboratory for Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; Department of Chemistry, University of California, Davis, CA 95616, United States. Electronic address: zhzhou@xmu.edu.cn.
Abstract
Unlike the most of α-alkoxy coordination in α-hydroxycarboxylates to vanadium, novel α-hydroxy coordination to vanadium(IV) has been observed for a series of chiral and achiral monomeric α-hydroxycarboxylato vanadyl complexes [VO(H2cit)(bpy)]·2H2O (1), [VO(Hmal)(bpy)]·H2O (2), [VO(H2cit)(phen)]·1.5H2O (3), [VO(Hmal)(phen)]·H2O (4), and [(Δ)VO(S-Hcitmal)(bpy)]·2H2O (5), [VO(H2cit)(phen)]2·6.5H2O (6), which were isolated from the reactions of vanadyl sulfate with α-hydroxycarboxylates and N-heterocycle ligands in acidic solution. The complexes feature a tridentate citrate, malate or citramalate that chelates to vanadium atom through their α-hydroxy, α-carboxy and β-carboxy groups; while the other β-carboxylic acidic group of citrate is free to participate strong hydrogen bonds with lattice water molecule. The neutral α-hydroxy group also forms strong intermolecular hydrogen bonds with water molecule and the negatively-charged α-carboxy group in the environment. The inclusion of a hydrogen ion in α-alkoxy group results in the formation of a series of neutral complexes with one less positive charge. There are two different configurations of citrate with respect to the trans-position of axial oxo group, where the complex with trans-hydroxy configuration seems more stable with less hindrance. The average bond distances of V-Ohydroxy and V-Oα-carboxy are 2.196 and 2.003Å respectively, which are comparable to the VO distance (2.15Å) of homocitrate in FeV-cofactor of V-nitrogenase. A new structural model is suggested for R-homocitrato iron vanadium cofactor as VFe7S9C(R-Hhomocit) (H4homocit=homocitric acid) with one more proton in homocitrate ligand.
Unlike the most of α-alkoxy coordination in α-hydroxycarboxylates to n class="Chemical">vanadium, novel α-hydroxy coordination to vanadium(IV) has been observed for a series of chiral and achiral monomeric α-hydroxycarboxylato vanadyl complexes [VO(H2cit)(bpy)]·2H2O (1), [VO(Hmal)(bpy)]·H2O (2), [VO(H2cit)(phen)]·1.5H2O (3), [VO(Hmal)(phen)]·H2O (4), and [(Δ)VO(S-Hcitmal)(bpy)]·2H2O (5), [VO(H2cit)(phen)]2·6.5H2O (6), which were isolated from the reactions of vanadyl sulfate with α-hydroxycarboxylates and N-heterocycle ligands in acidic solution. The complexes feature a tridentate citrate, malate or citramalate that chelates to vanadium atom through their α-hydroxy, α-carboxy and β-carboxy groups; while the other β-carboxylic acidic group of citrate is free to participate strong hydrogen bonds with lattice water molecule. The neutral α-hydroxy group also forms strong intermolecular hydrogen bonds with water molecule and the negatively-charged α-carboxy group in the environment. The inclusion of a hydrogen ion in α-alkoxy group results in the formation of a series of neutral complexes with one less positive charge. There are two different configurations of citrate with respect to the trans-position of axial oxo group, where the complex with trans-hydroxy configuration seems more stable with less hindrance. The average bond distances of V-Ohydroxy and V-Oα-carboxy are 2.196 and 2.003Å respectively, which are comparable to the VO distance (2.15Å) of homocitrate in FeV-cofactor of V-nitrogenase. A new structural model is suggested for R-homocitrato ironvanadium cofactor as VFe7S9C(R-Hhomocit) (H4homocit=homocitric acid) with one more proton in homocitrate ligand.
Authors: Oliver Einsle; F Akif Tezcan; Susana L A Andrade; Benedikt Schmid; Mika Yoshida; James B Howard; Douglas C Rees Journal: Science Date: 2002-09-06 Impact factor: 47.728
Authors: M Tsaramyrsi; M Kaliva; A Salifoglou; C P Raptopoulou; A Terzis; V Tangoulis; J Giapintzakis Journal: Inorg Chem Date: 2001-11-05 Impact factor: 5.165
Authors: Manuel Aureliano; Teresa Tiago; Ricardo M C Gândara; Andrea Sousa; A Moderno; M Kaliva; A Salifoglou; Rui O Duarte; José J G Moura Journal: J Inorg Biochem Date: 2005-10-10 Impact factor: 4.155
Authors: Dieter Rehder; João Costa Pessoa; Carlos F G C Geraldes; MargaridaM C A Castro; Themistoklis Kabanos; Tamás Kiss; Beate Meier; Giovanni Micera; Lage Pettersson; Maria Rangel; Athanasios Salifoglou; Iztok Turel; Dongren Wang Journal: J Biol Inorg Chem Date: 2001-12-19 Impact factor: 3.358
Authors: Nuttaporn Samart; Zeyad Arhouma; Santosh Kumar; Heide A Murakami; Dean C Crick; Debbie C Crans Journal: Front Chem Date: 2018-11-20 Impact factor: 5.221