The Coordination and Bioinorganic Chemistry of Molybdenum

Polymer-supported Mo and V cyclohexene epoxidation catalysts: Activation, activity, and stability

RECENT measurements of electron spin resonance1 have indicated that, in the reduced form of the molybdoflavo-protein enzyme xanthine oxidase, molybdenum(V) is coordinated with one or more sulphur atoms, probably ionized thiol groups of cysteine. Molybdenum–sulphur complexes have therefore attracted considerable interest as possible models for molybdenum in enzymes2. Although the chemistry of molybdenum–sulphur complexes is becoming well understood3, there has been little work on complexes with cysteine. Stability constants of complexes of molybdenum(V) and (VI) with cysteine have been reported4, but no complexes have been isolated. We now report the preparation and properties of a molybdenum(V)–cysteine complex, sodium di-μ-oxo-bis {oxo[cysteinato(2-)]aquomolybdate(V)} trihydrate, Na2 {Mo2O4[SCH2CH(NH2)CO2]2(H2O)2}3H2O, and discuss how far it can be regarded as a model for molybdenum in enzymes.

Molybdenum–Cysteine Complex

Spontaneous self-assembly of a giant spherical metal-oxide Keplerate: addition of one building block induces “immediate” formation of the complementary one from a constitutional dynamic library

P.C.H. Mitchell

Papers

The co-ordination chemistry of molybdenum—II(1)