transition metal sulfate complex

Sulfate binds to metals through one, two, three, or all four oxygen atoms.{{cite journal |doi=10.1002/ejic.200700063 |title=Use of the Sulfato Ligand in 3d-Metal Cluster Chemistry: A Family of Hexanuclear Nickel(II) Complexes with 2-Pyridyl-Substituted Oxime Ligands |date=2007 |last1=Papatriantafyllopoulou |first1=Constantina |last2=Aromi |first2=Guillem |last3=Tasiopoulos |first3=Anastasios J. |last4=Nastopoulos |first4=Vassilios |last5=Raptopoulou |first5=Catherine P. |last6=Teat |first6=Simon J. |last7=Escuer |first7=Albert |last8=Perlepes |first8=Spyros P. |journal=European Journal of Inorganic Chemistry |volume=2007 |issue=18 |pages=2761–2774 }}

Among the handful of complexes containing sulfate (or sulfato) ligands, most examples feature unidentate or chelating bidentate sulfate. Well characterized xamples are found with cobalt(III) ammines since these complexes are exchange inert. Monodentate sulfate is found in [Co(tren)(NH₃)(SO₄)]⁺ (tren = tris(2-aminoethyl)amine){{cite journal |doi=10.1002/(SICI)1099-0682(200001)2000:1<189::AID-EJIC189>3.0.CO;2-V |title=The Interaction between Amminehalocobalt(III) Cations and Polythionate Anions: Hydrogen-Bonding Patterns and S–S Bond Cleavage Reactions |date=2000 |last1=Chun |first1=Hyungphil |last2=Jackson |first2=W. Gregory |last3=McKeon |first3=Josephine A. |last4=Somoza |first4=Fernando B. |last5=Bernal |first5=Ivan |journal=European Journal of Inorganic Chemistry |volume=2000 |pages=189–193 }} Although {{chem2|[Co(en)2O2SO2]+}} is unknown, {{chem2|[(en)2Co(OS(O)2O)2Co(en)2](2+)}} forms instead (en = ethylenediamine). Bidentate sulfate is observed crystallographically in {{chem2|[Co(tetraamine)O2SO2]+}}.{{cite book |doi=10.1002/0470862106.ia046 |chapter=Cobalt: Inorganic & Coordination ChemistryBased in part on the article Cobalt: Inorganic & Coordination Chemistry by David A. Buckingham which appeared in the Encyclopedia of Inorganic Chemistry, First Edition |title=Encyclopedia of Inorganic Chemistry |date=2005 |last1=Blackman |first1=Allan G. |isbn=978-0-470-86078-6 }}

Sulfate function as a tridentate bridging ligand {{chem2|[Re3Cl9(SO4)](2-)}}.{{cite journal |doi=10.1002/zaac.19905870121 |title=Sulfat, Phosphat und Arsenat als dreizähnige Liganden. Synthese und Kristallstrukturen von (NMe₄)₂[Re₃Cl₉O₃SO], (NMe₄)₂(H₇O₃)[Re₃Cl₉O₃PO] und (NMe₄)₂(H₅O₂)[Re₃Cl₉O₃AsO] |date=1990 |last1=Irmler |first1=Manfred |last2=Meyer |first2=Gerd |journal=Zeitschrift für Anorganische und Allgemeine Chemie |volume=587 |pages=197–207 }}

All four oxygen atoms of sulfate bond to metals in some Dawson-type polyoxometalates, e.g. [S₂Mo₁₈O₆₂]^4-.{{cite journal |doi=10.1021/ic010780s |title=Electrochemical, Spectroscopic, Structural, and Magnetic Characterization of the Reduced and Protonated α-Dawson Anions in [Fe(η⁵-C₅Me₅)₂]₅[HS₂Mo₁₈O₆₂]·3HCONMe₂·2Et₂O and [NBu₄]₅[HS₂Mo₁₈O₆₂]·2H₂O¹ |date=2002 |last1=Juraja |first1=Suzy |last2=Vu |first2=Truc |last3=Richardt |first3=Peter J. S. |last4=Bond |first4=Alan M. |last5=Cardwell |first5=Terence J. |last6=Cashion |first6=John D. |last7=Fallon |first7=Gary D. |last8=Lazarev |first8=Georgii |last9=Moubaraki |first9=Boujemaa |last10=Murray |first10=Keith S. |last11=Wedd |first11=Anthony G. |journal=Inorganic Chemistry |volume=41 |issue=5 |pages=1072–1078 |pmid=11874340 }}

Tutton's salts, with the formula M'₂M(SO₄)₂(H₂O)₆ (M' = K⁺, etc.; M = Fe²⁺, etc.), illustrate the ability of water to outcompete sulfate as a ligand for M²⁺. Similarly alums, such as chrome alum ([K(H₂O)₆][Cr(H₂O)₆][SO₄]₂), features {{chem2|[Cr(H2O)6](3+)}} with noncoordinated sulfate. In a related vein, some sulfato complexes confirmed by X-ray crystallography, convert to simple aquo complexes when dissolved in water. Copper(II) sulfate examplifies this behavior, sulfate is bonded to copper in the crystal but dissociates upon dissolution.

[[File:CSD CIF HUXMIX.png|thumb|Structure of [Pt(NH₃)₄(NO)(SO₄)]⁺. Selected bond distances: Pt-O, 2.284; S-O range from 1.496 to 1.462 Å.

{{cite journal |doi=10.1021/ic901392q |title=Photogeneration of Nitrosyl Linkage Isomers in Octahedrally Coordinated Platinum Complexes in the Red Spectral Range |date=2009 |last1=Schaniel |first1=Dominik |last2=Woike |first2=Theo |last3=Behrnd |first3=Norwid-R. |last4=Hauser |first4=Jürg |last5=Krämer |first5=Karl W. |last6=Todorova |first6=Teodora |last7=Delley |first7=Bernard |journal=Inorganic Chemistry |volume=48 |issue=23 |pages=11399–11406 |pmid=19863116 }} Color code: blue = N, red = O, dark blue = Pt.]]

Sulfato complexes are commonly produced by reaction of metal sulfates with other ligands.

In some cases, sulfato complexes are produced from sulfur dioxide:{{cite journal |doi=10.1021/ja00988a057 |title=Oxidation of Coordinated Ligands. Sulfato and Nitrato Complexes of Platinum |date=1967 |last1=Cook |first1=Christopher David. |last2=Jauhal |first2=G. S. |journal=Journal of the American Chemical Society |volume=89 |issue=12 |pages=3066–3067 }}

:{{chem2 | Pt(O2)(PPh3)2 + SO2 -> Pt(SO4)(PPh3)2 }} (PPh₃ = triphenylphosphine)

Sulfato complexes also arise by air-oxidation of metal sulfides.{{cite journal |doi=10.1021/ic00063a004 |title=Dimerization of the Molybdenum Complex [(SO₄)Mo(O)(μ-S)₂Mo(O)(SO₄)]^2- Dianions Stabilized by a Quadruply Bridging Sulfate Ligand and Intramolecular Hydrogen Bonding by the [(CH₃)₂NH₂]⁺ Cations. Structures of the [(CH₃)₂NH₂]_6-x(Et₄N)_x[(SO₄)Mo(O)(μ-S)₂Mo(O)(SO₄)]₂(SO₄)] Aggregates (x = 1, 2, 2.5) |date=1993 |last1=Kim |first1=Chang G. |last2=Coucouvanis |first2=Dimitri |journal=Inorganic Chemistry |volume=32 |issue=11 |pages=2232–2233 }}

A dominant reaction of sulfato complexes is solvolysis, i.e. displacement of sulfate from the first coordination sphere by polar solvents such as water.

Sulfato complexes are susceptible to protonation of uncoordinated oxygen atoms.{{cite journal |doi=10.1021/ic00299a010 |title=Reactions of Sulfur Dioxide with Iron Porphyrinates and the Crystal Structure of (Hydrogen Sulfato)(tetraphenylporphinato)iron(III) Hemibenzene Solvate |date=1988 |last1=Scheidt |first1=W. Robert |last2=Lee |first2=Young Ja |last3=Finnegan |first3=Michael G. |journal=Inorganic Chemistry |volume=27 |issue=26 |pages=4725–4730 }}

• Co(phen)₂SO₄{{cite journal |doi=10.1107/S1600536812049616 |title=Bis(1,10-phenanthroline-κ² N , N ′)(sulfato-κ² O,O ′)cobalt(II) Propane-1,2-diol Monosolvate |date=2013 |last1=Zhong |first1=Kai-Long |journal=Acta Crystallographica Section E |volume=69 |issue=Pt 1 |pages=m26 |pmid=23476325 |pmc=3588351 }}

{{Coordination complexes}}

Category:Ligands

Category:Coordination chemistry

Category:Sulfates