Inorganic Chemistry, Vol.53, No.3, 1370-1381, 2014
Novel Trisphosphine Ligand Containing 1,3,5-Triazine Core, [2,4,6-C3N3{C6H4PPh2-p}(3)]: Synthesis and Transition Metal Chemistry
The trisphosphine ligand with triazine core, 2,4,6-tris{4-(diphenylphosphino)phenyl}-1,3,5-triazine (2), was synthesized in moderate yield by reacting 2,4,6-tris(4-bromophenyl)-1,3,5-triazine with 3 equiv of ICPPh2. The tris(phosphine) 2 undergoes facile oxidation to give trischalcogenides 2,4,6-C3N3{C6H4P(E)Ph-2-p}(3) (E = O, 3; S, 4; Se, 5) on treatment with aqueous H2O2, elemental sulfur, or selenium. The reaction between 2 and [AuCl(SMe2)] yielded a trinuclear complex, [(AuCl)(3){2,4,6-C3N3(C6H4PPh2-p)(3)}] (6), which on further treatment with pyridyl ligands such as 2,2'-bipyridine (2,2'-bpy) and 1,10-phenanthroline (1,10-phen) produced the mixed-ligand complexes [{Au(2,2'-bpy)}(3){2,4,6-C3N3(C6H4PPh2-p)(3)}]-(OTf)(3) (7) and [{Au(1,10-phen)}(3){2,4,6-C3N3(C6H4PPh2-p)(3)}](OTf)(3) (8), where OTf indicates trifluoromethansulfonate. Several trimetallic complexes such as [{Ru(eta(6)-cymene)Cl-2}(3){2,4,6-C3N3(C6H4PPh2-p)(3)}] (9), [{Pd(eta(3)-C3H5)Cl}(3){2,4,6-C3N3(C6H4PPh2-p)(3)}] (10), [{Rh(COD)Cl}(3){2,4,6-C3N3(C6H4PPh2-p)(3)}] (11) and [{Ir(COD)Cl}(3){2,4,6-C3N3(C(6)H(4)PPh(2-)p)(3)}] (12) have also been synthesized and characterized. The reactions of 2 with [M(COD)Cl-2] and CuI afforded metallocyclophane type complexes, [(MCl2)(3)L-2] (M = Pd; 13, Pt; 14) (L = 2,4,6-tris{4-(diphenylphosphino)phenyl}-1,3,5-triazine) and [(CuI)(3)L-2] (15), in good yield.