Molybdenum-Mediated Insertion of Ketones into the P-P bond of cyclo-(P Ph ) and Formation of Trinuclear Molybdenum Complexes.

The reaction of cyclopentaphosphine cyclo-(P Ph ) (1) with ketones (acetone and cyclooctanone) in the presence of [Mo(CO) (cod)] (cod=cycloocta-1,5-diene) led to air-stable trinuclear complexes in which the bis-phosphanido ligands (PPh-PPh-PPh-PPh-CMe O-PPh) (complex 2) and (PPh-PPh-PPh-PPh-C(CH ) O-PPh) (complex 3) bridge a Mo(CO) -Mo(CO) unit. This extends the reaction of 1 with transition metal carbonyl complexes to further substrates and represents the first examples of insertion of carbonyl compounds into the P-P bond of cyclic oligophosphorus compounds. Complexes 2 and 3 have been characterized by P NMR spectroscopy and single crystal X-ray diffraction. Furthermore, the thermal properties of the obtained complexes have been studied by differential scanning calorimetry (DSC) and fast scanning calorimetry (FSC).