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.

Bis(α-hydroxycycloalkyl)phosphine Oxides Obtained from White Phosphorus via Phosphine Oxide H PO: Synthesis, Molecular Structure, Coordination Properties and Biological Activity.

Reaction of the electrochemically in situ from elemental white phosphorus generated phosphine oxide H PO in a single electrochemical cell, supplied with lead cathode and aluminium anode, with cyclic ketones (cyclopentanone and cyclohexanone) results in formation of secondary phosphine oxides (bis(α-hydroxycyclopentyl)phosphine oxide 2 a, isolated yield 15 %, and bis(α-hydroxycyclohexyl)phosphine oxide 2 b, isolated yield 12 %) with two α-hydroxycycloalkyl substituents at the phosphorus atom. Bis(α-hydroxycyclopentyl)phosphine oxide reacts with [PdCl (COD)] (COD=1,5-cyclooctadiene) to give a new palladium complex trans-[PdCl {P(OH)(cyclo-C H -1-OH) } ] (3 a, isolated yield 11 %) bearing phosphinous acid as a ligand formed via tautomerization of the phosphine oxide. Finally, the cytotoxicity of the synthesized secondary phosphine oxides on tumor and healthy human cell lines was studied.