View : 15 Download: 0

Enclosure of a Keggin-type heteropolyoxometalate into a tubular π-space via hydrogen bonds with a nonplanar Mo(v)-porphyrin complex forming a supramolecular assembly

Title
Enclosure of a Keggin-type heteropolyoxometalate into a tubular π-space via hydrogen bonds with a nonplanar Mo(v)-porphyrin complex forming a supramolecular assembly
Authors
Yokoyama A.Kojima T.Fukuzumi S.
Ewha Authors
Shunichi Fukuzumi
SCOPUS Author ID
Shunichi Fukuzumiscopus
Issue Date
2011
Journal Title
Dalton Transactions
ISSN
1477-9226JCR Link
Citation
vol. 40, no. 24, pp. 6445 - 6450
Indexed
SCI; SCIE; SCOPUS WOS scopus
Abstract
A 2:1 supramolecular assembly composed of a non-planar Mo(v)-porphyrin, [Mo(DPP)(O)(H2O)]+ (1) (DPP2+; dodecaphenylporphyrin), and a Keggin-type heteropolyoxometalate (POM), α-[(n-butyl)4N]2[SW12O40] (2), was formed via hydrogen bonds. The crystal structure was determined by X-ray crystallography to clarify that the POM was enclosed into a π-space of a supramolecular porphyrin nanotube by virtue of a hydrogen-bond network. In contrast to the formation of the 2:1 assembly ([{Mo(DPP)(O)(H 2O)}2(SW12O40)] (3)) between 1 and [SW12O40]2- in the crystal, it was revealed that those two components form a 1:1 assembly in solution, in light of the results of MALDI-TOF-MS measurements in PhCN. Variable-temperature UV-vis spectroscopic titration allowed us to determine the thermodynamic parameters for the formation of the 1:1 supramolecular assembly in solution, the heat of formation (ΔH) and the entropy change (ΔS). These results provide the first thermodynamic data set to elucidate the formation process of supramolecuar structures emerged by hydrogen bonding between metalloporphyrin complexes and POMs, indicating that the formation of the assembly is an entropy-controlled process rather than an enthalpy-controlled one. Comparisons of the thermodynamic parameters with those of a planar Mo(v)-porphyrin complex also highlighted high Lewis acidity of the Mo(v) centre in the distorted porphyrin. © 2011 The Royal Society of Chemistry.
DOI
10.1039/c0dt01708f
Appears in Collections:
자연과학대학 > 화학·나노과학전공 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE