Luminescent Sensing and Catalytic Performances of a Multifunctional Lanthanide‐Organic Framework Comprising a Triphenylamine Moiety

Abstract

A multifunctional lanthanide‐organic framework Tb−TCA (H3TCA = tricarboxytriphenylamine) comprising a triphenylamine moiety as an efficient luminescence sensitizer is synthesized by a solvothermal method and structurally characterized. Tb−TCA exhibits lanthanide‐based emission (540 nm) and triphenylamine emission (435 nm) after excitation at 350 nm and works as a luminescent chemosensor towards salicylaldehyde with a sensitivity of 10 ppm under optimized conditions. Tb−TCA features a high concentration of Lewis acid Tb3+ sites and Lewis base triphenylamine sites on its internal surfaces; it thus enables both Knoevenagel and cyanosilylation reactions in a size‐selective fashion. The ratiometric fluorescent response towards aldehydes (I540/I435) demonstrates that the absorption of the porous material is size selective, and the interactions between the aldehyde molecules and the Tb3+ ions play a dominant role in the absorption and activation of the aldehyde substrates. In particular, these studies provide opportunities to directly validate the sorption sites and the catalytic mechanism of the multifunctional Ln metal–organic framework material by luminescence.

Sensing-functional luminescent metal–organic frameworks

“…78 Many examples of luminescent MOFs have been reported for sensing of biomolecules. [79][80][81][82][83][84] The recognition and detection of salicylaldehyde (SA) was demonstrated by Duan et al 79 80 Kumar et al realized the sensing of Bovine serum albumin (BSA) in an aqueous medium by using the MOFs tagged with an anti-BSA antibody. 81 In addition, Lin et al employed the MOF Cu(H 2 dtoa) (H 2 dtoa = Dithiooxamide) as a sensing platform which can adsorb probe DNA and release it upon the addition of target molecules, thus causing the fluorescence change.…”

Metal Organic Frameworks as Solid Catalysts in Condensation Reactions of Carbonyl Groups

“…[39] PbA C H T U N G T R E N N U N G (cpna) 2 ·2 DMF·6 H 2 O B A M N C H 3 CN r.t. [40] A [42] ZIF-8 BA MN toluene r.t. [43] ZIF-9 BA MN toluene r.t. [44] Pd [45] POM@MIL-101(Cr) BA ECA toluene 40 [46] PTA@MIL-101(Cr) BA 2-naphthol -90 [47] Tb-tca SA MN -r.t. [48] A [50] Condensation reactions catalyzed through proposed base catalysis ED-MIL-101(Cr) BA ECA C 6 H 12 80 [35] DETA-MIL-101(Cr) BA MN toluene r.t. [51] NH 2 -MIL-101(Cr) BA ECA toluene 60 [52] NH 2 -MIL-101(Al) BA ECA toluene 40 [53] NH 2 -MIL-101(Fe) BA MN toluene 80 [54] Zn [55] IRMOF-3 BA ECA DMF 40 [34] IRMOF-3 re-examination BA ECA ethanol 60 [56] SIM [59] Friedländer, Henry, aldol, Claisen-Schmidt and Pechmann condensation [61] Cu 3 A C H T U N G T R E N N U N G (btc) 2 APD FPD toluene 40 [62] FeA C H T U N G T R E N N U N G (btc) BA AP toluene 110 [63] MIL-101(Cr) acetone --180 [64] MIL-101-SO 3 H-NH 2 BADA NM -90 [65] CuA C H T U N G T R E N N U N G (padi) BADA MN DMSO-d 6 50 [66] A [68] UiO-66A C H T U N G T R E N N U N G (NH 2 ) BA heptanal -120 [69] Cu convenient from the environmental point of view considering the high biotoxicity of this metal. [39] PbA C H T U N G T R E N N U N G (cpna) 2 ·2 DMF·6 H 2 O B A M N C H 3 CN r.t. [40] A [42] ZIF-8 BA MN toluene r.t. [43] ZIF-9 BA MN toluene r.t. [44] Pd [45] POM@MIL-101(Cr) BA ECA toluene 40 [46] PTA@MIL-101(Cr) BA 2-naphthol -90 [47] Tb-tca SA MN -r.t. [48] A [50] Condensation reaction...…”

“…[48] The presence of coordinatively unsaturated Lewis acid sites (Tb 3+ ) and Lewis base sites (triphenylamine) on its internal surface makes this MOF suitable to catalyze Knoevenagel reactions in a size-selective fashion. [48] The presence of coordinatively unsaturated Lewis acid sites (Tb 3+ ) and Lewis base sites (triphenylamine) on its internal surface makes this MOF suitable to catalyze Knoevenagel reactions in a size-selective fashion.…”

“…[48] The presence of coordinatively unsaturated Lewis acid sites (Tb 3+ ) and Lewis base sites (triphenylamine) on its internal surface makes this MOF suitable to catalyze Knoevenagel reactions in a size-selective fashion. In order to test the catalytic activity of Tb-tca, the reaction of SA with MN was performed with 2 mol% of catalyst at room temperature, observing 99% conversion of aldehyde in 6 h. [48] In contrast, 2-hydroxy-1naphthaldehyde (NSA) with molecular dimensions of 9.7 8.4 showed 20% conversion. These interactions between the aldehyde molecules and Tb 3+ ions play a dominant role in the adsorption and activation of the aldehyde molecules as reactants.…”

Redes metalorgânicas e suas aplicações em catálise

“…Wu et al 94 desenvolveram uma MOF à base de térbio que continha tanto sítios ácidos quanto básicos de Lewis, sendo os ácidos presentes no Tb 3+ e os básicos nos sítios de trifenilamina dos ligantes, apresentando atividade tanto para a cianosililação quanto para a reação Knoevenagel.…”