The photochemistry of aqueous solutions of [Co(CN)5H2O]2- in the presence of the polyammonium macrocyclic receptor [32]ane-N8H88+ was studied. The quantum yield for cyanide release in free [Co(CN)5H2O]2- (PHI = 0.003 at 313 nm, pH 1.5) is reduced approximately threefold in the presence of the protonated macrocycle, which provides evidence for the formation of a supramolecular structure. Further evidence for the supramolecular structure is obtained from the thermal anation of [Co(CN)5H2O]2- with Br- (40-degrees-C, pH 1.0), the rate of which is increased in the presence of [32]ane-N8H88+, suggesting that the ligand water is not involved in hydrogen bonds with the macrocycle. These results are interpreted in terms of possible supramolecular structures.
ISI Document Delivery No.: JD486Times Cited: 5
Cited Reference Count: 13
Parola, aj pina, f
Pina, Fernando/C-8161-2011; Parola, A. Jorge/F-4048-2010
Parola, A. Jorge/0000-0002-1333-9076
Elsevier science sa lausanne
Lausanne 1