Silver(I) derivatives with new functionalised acylpyrazolonates

Silver(I) acylpyrazolonate derivatives of formula [Ag(Q)(R3P)](2) and [Ag(Q)(R3P)(2)](3) (QH = 1-phenyl-3-methyl-4-R'(C=O)-pyrazol-5-one; QdegreesH, R' = furane; Q(S)H, R' = thiophene; R = Ph, Cy, o-tol), have been synthesised and characterised, both in the solid state and in solution. The derivatives [Ag(Q)(R3P)](2) contain dinuclear AgO2NP units with the acylpyrazolonate coordinating in a bridging O,O'-Q-N fashion. The [A-(Q)(R3P)(2)] are tetrahedral species, with the distortion from ideal geometry increasing with the bulk of the phosphine. The [Ag(Q)(R3P)(2)] derivatives are fluxional in chloroform solution when R3P is sterically hindered (R = Cy or o-tol), dissociating partially to the [Ag(Q)(R3P)] fragment and free R,P. [Ag(Q(S))(Ph3P)](2) reacts with 1-methyl-2-mercaptoimidazole (Hmimt) affording the compound [Ag(Hmimt)(Ph3P)(Q(S))] and [Ag(Q(O))(Ph3P)](2) reacts with 1-methyl-imidazole (Meim) affording the compound [Ag(Meim)(Ph3P)(Q(O))], whereas [Ag(Q(S))(Ph3P)](2) reacts with 1,10-phenanthroline (phen), affording the compound [Ag(phen)(Ph3P)](Q(S)). Finally [Ag(Q(S))(Ph3P)(2)] reacts with phen producing the ionic species [Ag(phen)(Ph3P)(2)](Q(S)).