DPP Dyes as Ligands in Transition-Metal Complexes

摘要

The DPP dyes (=diketo-pyrolopyrrole) 1 are deprotonated to give the corresponding dianions 2. These are treated with two moles of the transition-metal complexes [L_nMX] = [(Ph_3P)_2MX] (M = Cu, Ag; X = Cl, NO_3), [(Ph_3P)AuCl], [(Et_3P)AuCl], [(tBuNC)AuCl], [(Ph_3P)_2PdCl_2], and [(Ph_3P)_2PtCl_2] to give the novel bismetalated DPP dyes [L_nM-N{C_3R~1(O)}_2N-ML_n] (4-10). In comparison with the starting materials, these compounds show better solubilities, high fluorescence quantum yields (#PHI# >= 80%), and bathochromic absorptions. The compounds 4c, 5a, 6b, 6c, 6e, 7c, and 8c were characterized by X-ray crystallography. The copper and silver atoms in 4c and 5a are trigonal planar and are surrounded by the P atoms of the phosphane ligands and the N atom of the DPP dianion 2. Both metals are somewhat forced out-of-plane, and the P_2M plane and the phenyl planes of R~1 are twisted by >70 deg and <25 deg, respectively, towards the chromophore plane. The gold atoms in 6-8 are linearly coordinated to one N and one P (6b, c, e, 7c) or one C atom (8c), respectively. The gold atoms are only slightly pressed out-of-plane, and ht P substituents are staggered so that there is enough space for the planarization of R~1 into the plane of the chromophore. Compound 8c shows intermolecular d~(10)-d~(10) interactions between Au~I centers of different molecules, and these interactions lead to infinite chains of parallel orientated molecules in a gauche conformation of neighbors (torsion angle = 150 deg) in the crystal.