Reversible Binding of Solvent to Naked PbII Centers in Unusual Homoleptic Alkynyl-Based Pt2Pb2 Clusters

  1. Berenguer, J.R. 1
  2. Fernández, J. 1
  3. Gil, B. 1
  4. Lalinde, E. 1
  5. Sánchez, S. 1
  1. 1 Universidad de La Rioja

    Universidad de La Rioja

    Logroño, España


Chemistry - A European Journal

ISSN: 0947-6539

Year of publication: 2014

Volume: 20

Issue: 9

Pages: 2574-2584

Type: Article

DOI: 10.1002/CHEM.201303665 SCOPUS: 2-s2.0-84897627321 WoS: WOS:000331729700026 GOOGLE SCHOLAR lock_openOpen access editor

More publications in: Chemistry - A European Journal


Cited by

  • Scopus Cited by: 22 (11-01-2023)
  • Web of Science Cited by: 21 (06-02-2023)

JCR (Journal Impact Factor)

  • Year 2014
  • Journal Impact Factor: 5.731
  • Journal Impact Factor without self cites: 5.323
  • Article influence score: 1.433
  • Best Quartile: Q1
  • Area: CHEMISTRY, MULTIDISCIPLINARY Quartile: Q1 Rank in area: 22/157 (Ranking edition: SCIE)

SCImago Journal Rank

  • Year 2014
  • SJR Journal Impact: 2.526
  • Best Quartile: Q1
  • Area: Catalysis Quartile: - Rank in area: 9/50
  • Area: Organic Chemistry Quartile: - Rank in area: 6/191
  • Area: Chemistry (miscellaneous) Quartile: Q1 Rank in area: 23/458

Scopus CiteScore

  • Year 2014
  • CiteScore of the Journal : 9.8
  • Area: Chemistry (all) Percentile: 94
  • Area: Medicine (all) Percentile: 92


We report a series of luminescent sandwich-type clusters [Pt2Pb2(C≡CR)8] (R=Tol, 1; C6H4OMe-3, 2; C6H4OMe-4, 3) with a dynamic Pt2Pb2 metallic core, which is key to their intriguing stimuli-responsive photophysical properties. The solvent-free solids 1-3 display an orange emission ascribed to charge transfer from Pt-alkynyl fragments to a delocalized orbital with mixed Pt2Pb2/C≡CR nature, with a predominant lead contribution and Pb{dot operator}{dot operator}{dot operator}Pb bonding character (3MLCCT/3IL). They exhibit mechanical, color, and luminescence changes that are reversible and perceivable with the naked eye, which are attributed to small inter- and intramolecular structural modifications induced by gentle grinding. Interestingly, 1 and 2 also exhibit remarkable and fast reversible vapochromic responses to donor solvent vapors (acetone, THFMe-2: yellow; NCMe: green, vs. dry solids: orange). The structures of 1(acetone)2{dot operator}2(Me2CO), 2(acetone)3, and 2(THFMe-2)2 allow the vapochromic responses to be ascribed to the fast creation/disruption of solvate clusters [Pt2Pb2(C≡CR)8Sx] (x≥2), with concomitant electronic and geometrical modifications within the Pt2Pb2 core, which are easily accessible through a slight change in the stereochemical activity of the lone pair. The binding of one (or two) solvent molecules to Pb2+ increases the Pb{dot operator}{dot operator}{dot operator}Pb separation in the metallic core, causing a destabilization of the target orbital and larger energy gaps of the transitions. All the solvates exhibit remarkable rigidochromism upon a decrease in temperature, which is also associated with the gradual increase in the transannular Pb{dot operator}{dot operator}{dot operator}Pb separation, as revealed by X-ray crystallography of 1(acetone)2 at different temperatures. Investigation of the crystal lattice of 1{dot operator}CH2Cl2 and 3{dot operator}2CH2Cl2 further suggests that the lack of vapor stimuli response of complex 3 could be attributed to the presence of competitive additional secondary intermolecular Pb{dot operator}{dot operator}{dot operator}O(OMe) contacts, which give rise to a more compact network built up from extended chains of clusters. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.