ABSTRACT
In the title compound, [Cu(2)(C(10)H(12)O(4))(C(12)H(8)N(2))(2)(H(2)O)(2)](BF(4))(2)·H(2)O, the two Cu atoms are each chelated by the acetyl-acetonate unit of the 3,4-diacetyl-hexa-2,4-diene-2,5-diolate (tae) ligand. The Cu atoms are square-pyramidally penta-coordinated, with one bidentate 1,10-phenanthroline (phen) and the tae ligand basal and one water mol-ecule apical. The pyridyl rings of the phen ligands participate in π-π [centroid-centroid distance = 3.894â (3)â Å] and C-H ⯠π inter-actions, generating layers which are inter-connected through O-Hâ¯O and O-Hâ¯F hydrogen bonds between the water mol-ecules and the tetra-fluorido-borate anions. The F atoms of both tetra-fluorido-borate anions are each disordered over two positions of equal occupancy.
ABSTRACT
The reactions between [Pd(P-P)(OTf)2] (where P-P=dppp or dppf) and two different bipyridyl ligands (=1,3-bis(4-pyridylmethyl)urea and=1,3- bis(pyridinylmethyl)benzenedicarboxamide) containing hydrogen-bonding units have been studied. The X-ray crystal structures of three of these assemblies have been solved showing them to be the [2+2] metallo-macrocycles [Pd(P-P)(n)]2(OTf)4 [P-P=dppp, n=1, (); P-P=dppp, n=2, (); P-P=dppf, n=1, ()]. To confirm whether the dimeric assembly of one of these species () is retained in solution, several investigations have been carried out. 1H NMR studies in DMSO and high resolution ESI mass spectrometry have shown that is in equilibrium with a larger [3+3] metallo-macrocycle. The equilibrium between these two species can be modified by changing the temperature, concentration or solvent. Also, addition of certain anions (e.g. [H2PO4]-) to the mixture shifts the equilibrium favoring the formation of the [2+2] metallo-macrocycle over the [3+3] (initially present in a larger proportion).
ABSTRACT
A new di-nuclear palladium complex containing thiol-urea ligands has been prepared, structurally characterized and its interaction with anionic species studied in solution.
