Functionalization of metal-organic frameworks through the postsynthetic transformation of olefin side groups

Konrad Hindelang, Alexander Kronast, Sergei I. Vagin, Bernhard Rieger

Research output: Contribution to journalArticlepeer-review

41 Scopus citations

Abstract

For the first time, the adaptability of the C=C double bond as a versatile precursor for the postsynthetic modification (PSM) of microporous materials was extensively investigated and evaluated. Therefore, an olefin-tagged 4,4′-bipyridine linker was synthesized and successfully introduced as pillar linker within a 9,10-triptycenedicarboxylate (TDC) zinc paddle-wheel metal-organic framework (MOF) through microwave-assisted synthesis. Different reactions, predominately used in organic chemistry, were tested, leading to the development of new postsynthetic reactions for the functionalization of solid materials. The postsynthetic oxidation of the olefin side groups applying osmium tetroxide (OsO4) as a catalyst led to the formation of a microporous material with free vicinal diol functionalities. The epoxidation with dimethyldioxirane (DMDO) enabled the synthesis of epoxy-functionalized MOFs. In addition to that, reaction procedures for a postsynthetic hydroboration with borane dimethyl sulfide as well as a photoinduced thiol-ene click reaction with ethyl mercaptan were developed. For all of these PSMs, yields of more than 90 % were obtained, entirely maintaining the crystallinity of the MOFs. Since the direct introduction of the corresponding groups by means of pre-synthetic approaches is hardly possible, these new PSMs are useful tools for the functionalization of porous solids towards applications such as selective adsorption, separation, and catalysis. One MOF, many modifications: The postsynthetic transformation of C=C double bonds is a versatile synthetic strategy for the introduction of functional groups in metal-organic frameworks (MOFs). A zinc-based, olefin-tagged MOF was applied to develop epoxidation, dihydroxylation, hydroboration, and thiol-ene click reactions as new postsynthetic modifications (PSM). The discussed PSMs are high yielding, maintaining the crystallinity and porosity of the frameworks (see scheme).

Original languageEnglish
Pages (from-to)8244-8252
Number of pages9
JournalChemistry - A European Journal
Volume19
Issue number25
DOIs
StatePublished - 17 Jun 2013

Keywords

  • hydroboration
  • metal-organic frameworks
  • oxidation
  • postsynthetic modification
  • thiol-ene reaction

Fingerprint

Dive into the research topics of 'Functionalization of metal-organic frameworks through the postsynthetic transformation of olefin side groups'. Together they form a unique fingerprint.

Cite this