Tuning Supramolecular Chiral Architecture of Molecular Corners from Achiral Dipalladium(II) and Diplatinum(II) Complexes with Achiral Anthracyl Pyrazole Ligand

Abstract

A novel kind of coordination molecular corners [M2L2]([1=(bpy)Pd]2L2, 2=[(dmbpy)Pd]2L2, 3=[(phen)Pd]2L2,4=[(ppy)Pt]2L2, where bpy=2,2′-bipyridine, dmbpy=4,4′-dimethyl-2,2′-bipyridine, phen=1,10-phenanthroline, ppy=2-phenylpyridine) was synthesized through synergistic metal-metal bonding interaction and spontaneous deprotonation from the pyrazole linkers 4-(4-(anthracen-9-yl)phenyl)-3,5-dimethyl-1H-pyrazole(L). Three complexes 1~3 were characterized by single crystal X-ray diffraction,1H and13 C NMR, ESI-MS and fluorescence spectroscopy. The neutral organometallic corner [(ppy)Pt]2L24 was also determined by1 H and13C NMR, MALDITOF-MS and fluorescence spectroscopy. These achiral molecular corners assemble from different achiral dimetallic centers with the achiral ligand HL in quite different crystal structures, in particular, 3 with a [(phen)Pd]2assembling center crystallizes into a supramolecular chiral architecture.