A well-established strategy to synthesize heterogeneous,metal-organic framework(MOF)catalysts that exhibit nanoconfinement effects,and specific pores with highly-localized catalytic sites,is to use organic linkers con...A well-established strategy to synthesize heterogeneous,metal-organic framework(MOF)catalysts that exhibit nanoconfinement effects,and specific pores with highly-localized catalytic sites,is to use organic linkers containing organocatalytic centers.Here,we report that by combining this linker approach with reticular chemistry,and exploiting three-dimensioanl(3D)MOF-structural data from the Cambridge Structural Database,we have designed four heterogeneous MOF-based catalysts for standard organic transformations.These programmable MOFs are isoreticular versions of pcu IRMOF-16,feu UiO-68 and pillared-pcu SNU-8X,the three most common topologies of MOFs built from the organic linker p.p'-terphenyldicarboxylic acid(tpdc).To synthesize the four squaramide-based MOFs,we designed and synthesized a linker,4,4’-((3,4-dioxocyclobut-1-ene-1,2-diyl)bis(azanedyil))dibenzoic acid(Sq_tpdc),which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers.Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena.Therefore,the four MOFs share the same organocatalytic squaramide moiety,but confine it within distinct pore environments.We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations:a Friedel-Crafts alkylation and an epoxide ring-opening.Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences.展开更多
基金the Spanish MINECO(projects RTI2018-095622-B-I00,RTI2018-095038-B-I00)the Catalan AGAUR(project 2017 SGR 238)+1 种基金the ERC under the EU FP7(ER C-Co 615954)European Unions Horizon 2020 research and innovation program under grant agreement No.685727,and European Structural Funds(S2018/NMT-4367).It was alsofunded by the CERCA Program/Generalitat de Catalunya.ICN2 is supported by the Severo Ochoa program from the Spanish MINECO(G rant No.SEV-2017-0706).
文摘A well-established strategy to synthesize heterogeneous,metal-organic framework(MOF)catalysts that exhibit nanoconfinement effects,and specific pores with highly-localized catalytic sites,is to use organic linkers containing organocatalytic centers.Here,we report that by combining this linker approach with reticular chemistry,and exploiting three-dimensioanl(3D)MOF-structural data from the Cambridge Structural Database,we have designed four heterogeneous MOF-based catalysts for standard organic transformations.These programmable MOFs are isoreticular versions of pcu IRMOF-16,feu UiO-68 and pillared-pcu SNU-8X,the three most common topologies of MOFs built from the organic linker p.p'-terphenyldicarboxylic acid(tpdc).To synthesize the four squaramide-based MOFs,we designed and synthesized a linker,4,4’-((3,4-dioxocyclobut-1-ene-1,2-diyl)bis(azanedyil))dibenzoic acid(Sq_tpdc),which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers.Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena.Therefore,the four MOFs share the same organocatalytic squaramide moiety,but confine it within distinct pore environments.We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations:a Friedel-Crafts alkylation and an epoxide ring-opening.Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences.
