Control of the Thermal and Photochemical Aquation of the Hexacyanochromate(III) and Aquapentacyanochromate(III) Ions by Formation of a Supramolecular Structure with [32]ane-N8

Supramolecular interactions between Co(CN)5(SO3)4− and polyammonium macrocyclic receptors

“…A similar negligible effect on the absorption spectra of the co-ordination compound upon supercomplexation with polyammonium macrocycles was previously observed for hexacyanocobaltate(), 9-11 pentacyanoaquacobaltate(), 12 hexacyanochromate() and pentacyanoaquachromate(). 13 The difference between pK a ≈0.5 (supercomplex) and 3.9 (free complex) can be attributed to the positive charge of the macrocycle, which reduces the charge density on the ligands and on the metal center. An analogous effect of the charge of the macrocycle was previously reported for similar adducts, 12 and in other cases an anodic shift of the redox potential of the metal upon supercomplexation was also observed.…”

“…These modifications may also depend on (and thus provide information about) the geometrical structure of the adduct; for example, the thermal and photochemical reactivity of the ligands directly involved in second-sphere bonding are expected to be much more affected by the macrocycle than those of the other ligands. [9][10][11][12][13] In this work we are presenting the study of the supercomplexes formed between the pentacyanosulfitocobaltate() complex ion and some polyammonium macrocyclic receptors of different charge and dimensions shown in Fig. 1.…”

Kinetic control of the aquation of the Hexathiocyanatochromate(Iii) Ion by Associative interaction of Poly(Acrylamide) in Aqueous Medium

“…More mechanistic informations on the reaction rate can be obtained by investigating the kinetics in heterogeneous media. 1 Zinato et al 4 established that [Cr(CN) 6 ] 3undergoes reduced rate in a medium containing a polyaza-macrocyclic ligand. It appears to be more interesting to study the aquation of [Cr(NCS) 6 ] 3in the presence of an inert polymer like poly(acrylamide) PAA, to obtain additional information on the reaction mechanisms as well as on the interaction behaviour between complex and macromolecule.…”

Electron transfer between Fe(CN)63− and iodide promoted by supercomplexation with a polyammonium macrocycle

“…Some new properties promoted by the formation of a supercomplex between iron hexacyanometallates and the polyazamacrocycle [32]aneN 8 (1,5,9,13,17,21,25,29-octaazacyclodotriacontane) are described. In the presence of the polyazamacrocycle, thermal and photoinduced electron transfer from iodide to Fe(CN) 6 3Ϫ were observed in moderately acidic media.…”

“…The thermal and photochemical reactivity, as well as the redox, spectroscopic and photophysical properties of co-ordination compounds can be greatly modified by their inclusion into supramolecular structures (supercomplexes) involving appropriate macrocyclic receptors. [1][2][3][4][5][6][7][8][9][10][11][12] In these structures the macrocyclic receptor is bound by non-covalent interactions to the transition-metal complex, and thus can be viewed as a secondsphere co-ordination ligand. 2Ϫ and M(CN) 5 Br 3Ϫ (M = Co III 4 ) and M(bipy)(CN 4 ) 2Ϫ -(M = Ru II , bipy = 2,2Ј-bipyridine) 7 have been studied.…”