Ruthenium(II) Tris(2,2′-bipyridyl) Complex Incorporated in UiO-67 as Photoredox Catalyst

Abstract

Ruthenium(II) bis(2,2′-bipyridine) (2,2′-bipyridyl-5,5′-dicarboxylic acid), Rudcbpy, attached to the UiO-67(Zr) metal organic framework (MOF), generates upon visible light excitation the localized triplet excited state of the ruthenium(II) bipyridyl complex that decays partly to a very long-lived (millisecond time scale) photoinduced charge-separated state following a similar behavior as that of analogous ruthenium(II) tris(bipyridyl) complex dissolved in water, except that the lifetime of the soluble complex excited state is orders of magnitude shorter. The occurrence of photoinduced charge separation on the Rudcbpy-UiO-67(Zr) MOF has been proven visually by using methyl viologen as electron acceptor. Rudcbpy-UiO-67(Zr) behaves as a heterogeneous, reusable, photoredox catalyst promoting debromination of α-bromoketones with excellent selectivity at high conversions. Characterization data show that Rudcbpy-UiO-67(Zr) is stable under the photocatalytic reaction conditions.

Photoredox Catalysis Using Heterogenized Iridium Complexes

“…We were inspired by results from a Tris(bipyridine)Ru(II) metal organic framework (MOF) photoredox catalyst reported to catalyze reductive dehalogenation reactions. 39 In the reaction mixture, triethanolamine (TEOA)…”

Photoredox Catalysis Using Heterogenized Iridium Complexes

“…This reaction is advantageous as it is simple, well-known, and is easy to follow using 1 H NMR spectroscopy, making it an ideal reaction for initial catalytic studies. [39][40][41][42] Furthermore, the product APN is non-toxic and highly applicable in the perfume industry. Ultimately, we hope to generate an initial understanding of what materials and assembly methods provide the most functional and robust heterogenized photoredox catalysts.…”

“…A reaction scheme is depicted in Scheme 2 for the reductive dehalogenation of BrAPN to APN. We were inspired by results from a Tris(bipyridine)Ru(II) metal organic framework (MOF) photoredox catalyst reported to catalyze reductive dehalogenation reactions 39. In the reaction mixture, triethanolamine(TEOA) was also present to act as a sacrificial electron donor and proton source.…”

Subphthalocyanine encapsulated within MIL-101(Cr)-NH2 as a solar light photoredox catalyst for dehalogenation of α-haloacetophenones

“…This composite exhibits activity for the sunlight photoredox catalytic hydrogenative debromination of bromoacetophenone in the presence of electron donors (photoredox reaction). 14…”