Silver(I) poly(1,2,3-benzotriazolyl)borate complexes containing mono- and bidentate phosphine coligands

New silver(I) derivatives [Ag{HnB(btZ)(4-n) } (PR3)(x)] (n = 1 or 2, x ranging from 1 to 3), containing monodentate tertiary phosphines and anionic poly(benzotriazol-1-yl)borates, have been prepared from the reaction of AgNO3 with PR3 (R =Ph, o-tolyl, m-tolyl, p-tolyl, Bn) and K[H2B(btZ)(2)], or K[HB(btZ)(3)] (Hbtz = 1,2,3-benzotriazole). When the reaction between K[H2B(btZ)(2)] and AgNO3 was carried out in the presence of dppe (1,2-bis(diphenylphosphino)ethane), or dppf (1,1'-bis(diphenylphosphino)ferrocene), compounds [Ag{H2B(btz)(2)}](2)(L) (L = dppe or dppo formed, the diphosphine acting as a bidentate bridging P-2-donor. Solid state and solution properties of all complexes have been investigated through analytical and spectroscopic measurements (IR, H-1, P-31 NMR), the H-1 and P-31 NMR spectra being interpreted in terms of equilibria that involve mono- and di-nuclear complexes. Adducts [Ag{HB(btZ)(3)}(PPh3)(3)]center dot(1/2H(2)O) and [Ag{H2B(btZ)(2)}](2) (dppf) have been characterised by single crystal X-ray studies. In the former, the HB(btZ)(3) is unidentate in an NAgP3 coordination environment; the latter is a dimer, the dppf bridging the two silver atoms, while the H2B(btZ)(2) ligand, which chelates one silver, bridges to the second also, the array having 2-symmetry.