Reaction of RuH
2CO(PPh
3)
3 with tetrafluorosuccinic acid at 100
![](/images/entities/deg.gif)
C gave rise to the formation of thedinuclear bis(tetrafluorosuccinate)-bridged Ru(II) complex
2, containing two water ligands. Exchange ofthe PPh
3 in complex
2 with various diphosphine ligands afforded a series of analogous complexes
3.Reaction of the latter with 1-phenylethanol at 130
![](/images/entities/deg.gif)
C or with 2-propanol/Et
3N at room temperaturefurnished the dinuclear dihydrido-bridged Ru(II) complexes
4. Complexes
2 and
4 were characterized byX-ray diffraction analysis. Both bis(tetrafluorosuccinate)-bridged complexes
3 and dihydrido-bridgedcomplexes
4 catalyze the acceptorless dehydrogenation of 1-phenylethanol to acetophenone and dihydrogenwith good yields and excellent selectivity under relatively mild conditions in the absence of acid or base.A tentative catalytic cycle for the dehydrogenation of secondary alcohols by Ru(II) complexes of type
3is presented.