Reactivity of the phosphinito bridged Pt(i) complex [(PHCy_2)Pt(μ-PCy_2){κ~2P,O-μ-P(O)Cy_2}Pt(PHCy_2)](Pt-Pt) towards Au(i) and Ag(i) electrophiles

摘要

The reactivity of the phosphinito bridged Pt(i) complex [(PHCy_2)Pt~1(μ-PCy_2){κ~2P,O-μ- P(O)Cy_2}Pt2(PHCy_2)](Pt-Pt) (1) towards Au(i) and Ag(i) electrophiles was explored. Treatment of 1 with AuCl yielded the dichloro Pt(ii) complex [(Cl)(PHCy_2)Pt(μ-PCy_2) {κ~2P,O-μ-P(O)Cy_2}Pt(Cl)(PHCy_2)] (4), while [Au(PPh_3)Cl] in thf (or toluene) caused ligand exchange resulting in the formation of [(PPh_3)Pt(μ-PCy_2) {κ~2P,O-μ-P(O)Cy_2}Pt(PHCy_2)](Pt-Pt) (7) and [(PPh_3)Pt(μ-PCy_2){κ~2P,O-μ-P(O) Cy_2}Pt(PPh_3)](Pt-Pt) (8). With [Au(PPh_3)OTf] (independently from the solvent) or with [Au(PPh_3)Cl] (only in dichloromethane), reaction with 1 gave [(PHCy_2)Pt~1(μ- PCy_2){κ~2P,O-μ-P(O)Cy_2}Pt~2{μ-Au(PPh_3)}(PHCy_2)]X(Pt-Pt) ([6]X, X = OTf, Cl) clusters in which the [Au(PPh_3)] moiety bridges the μP-Pt2 bond. The [Ag(PPh_3)]~+ electrophile attacks complex 1 selectively at the Pt2-μP bond to afford, at low T, the cationic cluster [(PHCy_2)Pt~1(μ-PCy_2){κ~2P,O-μ-P(O)Cy_2}Pt~2{μ-Ag(PPh_3)}(PHCy_2)]~+(Pt-Pt) (10~+) in which the [Ag(PPh_3)]~+ moiety bridges the μP-Pt2 bond. Clusters analogous to 10+, but without PPh_3 bonded to Ag, are obtained from reactions of 1 with AgOTf, AgBF_4, AgClO_4 and AgCl.