Chiral structures of palladium(ii)-based triangular supramolecular complexes, with achiral corners and edges, have been characterized in solution.

A triangular palladium(II) supramolecular coordination complex based on 1,4-bis(1H-imidazol-1-yl)benzene and (2,2 0 0 0 -bipyridyl)palladium(II) nitrate: synthesis and crystal structureThe self-assembly of ditopic bis(1H-imidazol-1-yl)benzene ligands (L H ) and the complex (2,2 0 -bipyridyl-2 N,N 0 )bis(nitrato-O)palladium(II) affords the supramolecular coordination complex tris[-bis(1H-imidazol-1-yl)benzene-2 N 3 :N 3 0 ]triangulo-tris[(2,2 0 -bipyridyl-2 N,N 0 )palladium(II)] hexakis(hexafluoridophosphate) acetonitrile heptasolvate, [Pd 3 (C 10 H 8 N 2 ) 3 (C 12 H 10 N 4 ) 3 ](PF 6 ) 6 Á7CH 3 CN, 2. The structure of 2 was characterized in acetonitrile-d 3 by 1 H/ 13 C NMR spectroscopy and a DOSY experiment. The trimeric nature of supramolecular coordination complex 2 in solution was ascertained by cold spray ionization mass spectrometry (CSI-MS) and confirmed in the solid state by X-ray structure analysis. The asymmetric unit of 2 comprises the trimetallic Pd complex, six PF 6 À counter-ions and seven acetonitrile solvent molecules. Moreover, there is one cavity within the unit cell which could contain diethyl ether solvent molecules, as suggested by the crystallization process. The packing is stabilized by weak interand intramolecular C-HÁ Á ÁN and C-HÁ Á ÁF interactions. Interestingly, the crystal structure displays two distinct conformations for the L H ligand (i.e. syn and anti), with an all-syn-[Pd] coordination mode. This result is in contrast to the solution behaviour, where multiple structures with syn/anti-L H and syn/anti- [Pd] are a priori possible and expected to be in rapid equilibrium. # 2019 International Union of Crystallography research papers 524 Jean-Claude et al. A triangular palladium(II) supramolecular coordination complex Acta Cryst. (2019). C75, 523-528 Figure 1 Schematic representation of triangular SCCs A and B with syn/anti-L H and syn/anti-[Pd] conformations.