Synthesis, characterization, crystal structure and preliminary reactivity behaviour of new heteropolytopic ligands based on the 1,3,5-triazine spacer and pyrazolyl, tris-pyrazolylmethyl and tris-pyrazolylethoxy bonding fragments

Four new potentially polytopic nitrogen donor ligands based on the 1,3,5-triazine fragment, L1–L4 (L1 = 2-chloro-4,6-di(1H-pyrazol-1-yl)-1,3,5-triazine, L2 = N,N¢-bis(4,6-di(1H-pyrazol-1-yl)-1,3,5- triazin-2-yl)ethane-1,2-diamine, L3 = 2,4,6-tris(tri(1H-pyrazol-1-yl)methyl)-1,3,5-triazine, and L4 = 2,4,6-tris(2,2,2-tri(1H-pyrazol-1-yl)ethoxy)-1,3,5-triazine) have been synthesized and characterized. The X-ray crystal structure of L3 confirms that its molecular nature consists of a 1,3,5-triazine ring bearing three tripodal tris(pyrazolyl) arms. L1, L2, and L4 react with CuI, CuII, PdII and AgI salts yielding mono-, di-, and oligonuclear derivatives: [Cu(L1)(Cy3P)]ClO4, [{Ag2(L2)}(CF3SO3)2]·H2O, [Cu2(L2)(NO3)2](NO3)2·H2O, [Cu2(L2)(CH3COO)2](CH3COO)2·3H2O, [Pd2(L2)(Cl)4]·2H2O, [Ru(L2)(Cl)(OH)]·CH3OH, [Ag3(L4)2](CF3SO3)3 and [Ag3(L4)2](BF4)3. The interaction of L3 with AgI, CuII, ZnII and RuII complexes unexpectedly produced the hydrolysis of the ligand with formation, in all cases, of tris(pyrazolyl)methane (TPM) derivatives. In detail, the already known [Ag(TPM)2](CF3SO3) and [Cu(TPM)2](NO3)2, as well as the new [Zn(TPM)2](CF3SO3)2 and [Ru(TMP)(p-cymene)]Cl(OH)· 2H2O complexes have been isolated. Single-crystal XRD determinations on the latter derivatives confirm their formulation, evidencing, for the RuII complex, an interesting supramolecular arrangement of the anions and crystallization water molecules