LAUSR

The reactivity of the N-functionalized DPPA-type ligands (Ph2P)2N(p-Z)C6H4 [Z = H (1a), SMe (1b), OMe (1c)] with AgBF4 was investigated and revealed an unexpected influence of the para substituent Z of the N-aryl ligand. In acetone, the mononuclear bis-chelated [Ag{(1a-1c)-P,P}2]BF4 (2a·BF4-2c·BF4) and dinuclear bridged [Ag2{μ2-(1a-1c)-P,P}2](BF4)2 [3a·(BF4)2-3c·(BF4)2] complexes were obtained with a 1 : 2 and 1 : 1 AgBF4/ligand molar ratio, respectively. While the molecular structures of 2a·BF4 and 2b·BF4 determined in the solid-state by X-ray diffraction revealed their mononuclear nature and the absence of cation/anion interaction, complexes 3b·(BF4)2 and 3c·(BF4)2 form 2D coordination polymers through intermolecular Ag-S or Ag-O interactions, respectively, involving the N-function of the respective DPPA-type ligand, and display direct interactions between one BF4 anion and both Ag(i) cations. Surprisingly, the equimolar reaction between ligands 1a-1c and AgBF4 in CH2Cl2 led to different proportions of the dinuclear complexes 3a·(BF4)2-3c·(BF4)2 and clusters [Ag3(μ3-Cl)2{μ2-(1b-1c)-P,P}3]BF4 (4b·BF4-4c·BF4), depending on the nature of the para substituent Z of the N-aryl ligand. The trinuclear complexes resulted from C-Cl bond activation of the chlorinated solvent and were characterized by NMR spectroscopy and X-ray diffraction, and could be selectively produced by addition of 2/3 equiv. of [NMe4]Cl to the corresponding dinuclear complexes or by a one-pot procedure involving the correct amount of each reagent. A series of experiments and kinetic NMR investigations were performed to gain further insight into the formation of the trinuclear Ag3Cl2 core clusters.