Pyrazolate-Bridged Ruthenium I Carbonyl Complexes

This mixed metallocene is air-stable as a dry solid and melts at 89-90°C. It oxidizes slowly in solutions exposed to the air. It is very soluble in pentane, benzene, THF, and diethyl ether. It can be recrystallized from methanol. It sublimes without appreciable decomposition. 

SUBMITTED BY JAVIER A. CABEZA and LUIS A. ORO CHECKED BY RICHARD A. JONES  

The number of known ruthenium(I) carbonyl complexes is relatively small in comparison to those known for ruthenium(O) or ruthenium(II).1 Moreover, apart from [Ru2(C5H5)2(CO)4]2 and carboxylato complexes of the type [Ru2(/t-RC02)2(C0)4L2],3 whose syntheses are well established, most of the 

1 Instituto de Ciencia de Materiales de Aragon, Facultad de Ciencias, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain. 

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