Synthesis of novel trimeric µ-oxo-bridged manganese(IV) complexes: [L3Mn3IV(µ2-O)3(µ3-XO4)]Br3(X = P, As, or VV; L = 1,4,7-triazacyclononane)
Abstract
The reaction of (L2MnIII2(µ-O)(µ-MeCO2)2](CIO4)2 with Na2HPO4, (NH4)3VO4, or Na2HAsO4 in aqueous solution (pH ca. 9) in the presence of air yields, upon addition of NaBr, deep red crystals of [L3MnIV3(µ2-O)3(µ3-XO4)]Br3(X = P, As, or VV; L = 1,4,7-triazacyclononane); characterization of the µ-phosphato complex by X-ray crystallography showed the presence of discrete trimeric cations [L3MnIV3(µ-O)3(µ-PO4)]3+ where three MnIV centres are in a distorted octahedral fac-N3O3 donor set connected by three µ2-oxo bridges and a µ3-PO4 bridge.