Substitution chemistry of ruthenium clusters with the diphosphine ligands: 4,5-bis(diphenylphosphino)-4-cyclo-penten-1,3-dione (BPCD), (Z)-Ph(2)PCH=CHPPh(2) and 3,4-bis(diphenylphosphino)-5-methoxy-2(5H)-furanone (BMF)

The reaction between the redox-active diphosphine ligand bpcd and Ru{dollar}sb3{dollar}(CO){dollar}sb{lcub}12{rcub}{dollar} has been examined under a variety of conditions. Thermolysis of {dollar}rm Rusb3(CO)sb{lcub}12{rcub}{dollar} with bpcd affords the binuclear compounds {dollar}rm Rusb2(CO)sb6(bpcd){dollar} (3) and {dollar}rm Rusb2(CO)sb6lbrackmu{dollar}-{dollar}rm overline{lcub}C{lcub}={rcub}C(PPhsb2)C(O)CHsb2C{rcub}(O)rbrack (musb2{dollar}-PPh{dollar}sb2){dollar} (4) as the major and minor products, respectively. The disubstituted cluster {dollar}rm Rusb3(CO)sb{lcub}10{rcub}(bpcd){dollar} (2) has been synthesized and shown to contain a chelating bpcd ligand, on the basis of IR and {dollar}sp{lcub}31{rcub}{dollar}P NMR data. The cluster 2 (chelating isomer) undergoes cluster fragmentation at ambient temperatures in the dark to give the binuclear compound 3 and {dollar}rm Rusb3(CO)sb{lcub}12{rcub},{dollar} with no evidence for the formation of 4. Both 3 and 4 have been isolated and fully characterized in solution by IR and NMR spectroscopy, and the solid-state structure of each new binuclear compound has been established by X-ray diffraction analysis. Independent experiments reveal that dinuclear 3 is converted to 4 by 366 nm light with a quantum efficiency of 0.0364.; Near-UV irradiation of 3 in the presence of 11 equivalents of PMe{dollar}sb3{dollar} gave 4 (13%), {dollar}rm Rusb2(CO)sb5(bpcd)(PMesb3){dollar}(7)(5%), and {dollar}rm Rusb2(CO)sb5lbrack mu{dollar}-{dollar}rm overline{lcub}C{lcub}={rcub}C(PPhsb2)C(O)CHsb2C{rcub}(O)rbrack(musb2{dollar}-{dollar}rm PPhsb2){dollar}-(PMe{dollar}sb3){dollar} (8) (6%). Both 7 and 8 have been isolated and fully characterized in solution by IR and NMR spectroscopy, and the solid-state structure of each new binuclear compound has been established by X-ray diffraction analysis.; Irradiation of either {dollar}rm Rusb2(CO)sb6(bpcd){dollar} or {dollar}rm Rusb2(CO)sb6lbrack{dollar}(Z)-{dollar}rm Phsb2PCH{lcub}={rcub}CHPPhsb2rbrack{dollar} in {dollar}rm CHsb2Clsb2{dollar} solution with excess dimethyl acetylenedicarboxylate at room temperature furnishes the zwitterionic (Z)-dimetallated olefin complexes {dollar}rm Rusb2(CO)sb6(bpcd)lbrackmu{dollar}-(Z)-{dollar}rm MeOsb2CC{lcub}={rcub}CCOsb2Merbrack{dollar} (11) or {dollar}rm Rusb2(CO)sb6C{dollar}(Z)-{dollar}rm Phsb2PCH{lcub}={rcub}CHPPhsb2rbracklbrackmu{dollar}-(Z)-{dollar}rm MeOsb2CC{lcub}={rcub}CCOsb2Merbrack{dollar} (12), respectively. Both 11 and 12 have been isolated and fully characterized in solution by IR and NMR spectroscopy. The solid-state structure of 11 was determined by X-ray diffraction analysis.; The acetylide-bridged cluster {dollar}rm Rusb3(CO)sb9(musb2{dollar}-H)({dollar}musb3{dollar}-{dollar}etasp2{dollar}-{dollar}rm C{lcub}equiv{rcub}CBusp{lcub}t{rcub}){dollar} reacts with bpcd in {dollar}rm CHsb2Clsb2{dollar} with added {dollar}rm Mesb3NO{dollar} to afford the bpcd-substituted cluster {dollar}rm Rusb3(CO)sb7(musb2{dollar}-H)({dollar}musb3{dollar}-{dollar}etasp2{dollar}-{dollar}rm C{lcub}equiv{rcub}Busp{lcub}t{rcub}{dollar}(bpcd) (14) as the only product. Interestingly, under the same conditions the reaction of the related phenylacetylide cluster {dollar}rm Rusb3(CO)sb9(musb2H)(musb3{dollar}-{dollar}etasp2{dollar}-{dollar}rm C{lcub}equiv{rcub}CPh){dollar} with bpcd not only affords the chelating cluster {dollar}rm Rusb3(CO)sb7(musb2{dollar}-H)({dollar}musb3{dollar}-{dollar}etasp2{dollar}-{dollar}rm C{lcub}equiv{rcub}CPh){dollar}(bpcd) (15) but also gives, as major product, the zwitterionic cluster {dollar}rm Rusb3(CO)sb7(musb2{dollar}-H) ({dollar}musb3{lcub}:{rcub}etasp2,etasp2, etasp2,etasp1,eta sp1{dollar}-PhCC(PPh{dollar}sb2)rm overline{lcub}C{lcub}={rcub}C(PPhsb 2)C(O)CHsb2C{rcub}(O)rbrack{dollar} (16), whose origin can be traced to the attack of a PPh{dollar}...