Ru II complexes with -P, -As and -Sb Donors

Oxidations with the phosphorus-containing polyoxometalate [Ru(HjO) PWjj(0)3, r are considered above (1.9.1). 

RuCljCPPhj) After [RuO ] (n = 0-2), RuO and RuQj this is probably the most frequently used Ru oxidation catalyst, particularly for alcohol oxidations. Whereas the catalytic action of RUCI3 or RuO in most cases studied probably derives from their initial oxidation to [RuO ] , it is often not clear how RuCl CPPhj) operates as a catalyst. There are reviews on its oxidation chemistry [56, 58], Its CAS number is 15529-49-4. 

It is made by reaction of RuClj with PPh in methanol, and forms shiny black crystals [881, 882], The X-ray crystal structure shows the molecule to have a distorted square-based pyramidal structure, a phosphorus atom forming the axial bond (Ru-P 2.230(8) A) while the basal plane has two trans chloro ligands (Ru-C1 2.387(7) and 2.388(7) A) and two trans phosphine ligands (Ru-P 2.374(4) and 2.412(6) A). It can be regarded as octahedral, with the sixth position blocked by a phenyl ring (Fig. 1.39) [883]. The catalytic efficacy of the complex may well depend on the availability of this vacant coordination site. 

The system RuCl3(PPh3)3/TEMPO/O3(10 atm air)/CgH3Cl (TEMPO=2,2, 6,6 -tetramethyl-piperidine-iV-oxyl radical. Fig. 1.40) oxidised primary alcohols to aldehydes and secondary alcohols to ketones. Hammett correlation studies and primary 

Aerobic oxidation of primary alcohols to aldehydes and secondary alcohols to ketones was accomplished in ionic liquids (bmim, l-butyl-3-methyl-imidazolium cation) as RuCl2(PPh3)j/(bmim)V80°C RuClj or [RuCl Cp-cymene)] were also used 

---