Building blocks and COFs formed in concert —Three‐component synthesis of pyrene‐fused Azaacene covalent organic framework in the bulk and as films

A three‐component synthesis methodology is described for the formation of covalent organic frameworks (COFs) containing extended aromatics. Notably, this approach enables synthesis of the building blocks and COF along parallel reaction landscapes, on a similar timeframe. The use of fragmental building block components, namely pyrene dione diboronic acid as aggregation‐inducing COF precursor and the diamines o‐phenylenediamine (Ph), 2,3‐diaminonaphthalene (Naph), or (1R,2R)‐(+)‐1,2‐diphenylethylenediamine (2Ph) as extending functionalization units in conjunction with 2,3,6,7,10,11‐hexahydroxytriphenylene, resulted in the formation of the corresponding pyrene‐fused azaacene, i.e., Aza‐COF series with full conversion of the dione moiety, long‐range order, and high surface area. In addition, the novel three‐component synthesis was successfully applied to produce highly crystalline, oriented thin films of the Aza‐COFs with nanostructured surfaces on various substrates. The Aza‐COFs exhibit light absorption maxima in the blue spectral region, and each Aza‐COF presents a distinct photoluminescence profile. Transient absorption measurements of Aza‐Ph‐ and Aza‐Naph‐COFs suggest ultrafast relaxation dynamics of excited‐states within these COFs.Deutsche Forschungsgemeinschaft | Ref. ME 4515/1-2Fundação para a Ciência e a Tecnologia | Ref. SFRH/BD/141865/2018Fundação para a Ciência e a Tecnologia | Ref. PTDC/QUI-OUT/2095/2021Fundação para a Ciência e a Tecnologia | Ref. UIDB/50011/2020Fundação para a Ciência e a Tecnologia | Ref. UIDP/50011/2020Fundação para a Ciência e a Tecnologia | Ref. LA/P/0006/2020National Science Foundation (EE.UU.) | Ref. DMR-1848067Engineering and Physical Sciences Research Council (Reino Unido) | Ref. EP/V055127/1Agencia Estatal de Investigación | Ref. RYC2020-030414-IUniversidade de Vigo/CISU

A post-synthetic modification strategy for the synthesis of pyrene-fused azaacene covalent organic frameworks

Post-synthetic modification strategy is presented to extend the π-system of covalent organic framework (COF) backbone giving access to boronic ester based pyrene-fused azaacene COFs. Optimized catalyst-free reaction conditions yield COFs post-synthetically modified with up to 33% conversion and corresponding intriguing optical properties. The presented chemistry is expected to find application in post-synthetic tailoring of the optical properties of COFs.S.P.S.F. acknowledges the FCT − Fundação para a Ciência e Tecnologia for the Ph.D. scholarship SFRH/BD/131791/2017. This work received funding from the COFforH2 project (UTA-EXPL/NPN/0055/2019) through the Portuguese Foundation for Science and Technology funds under UT Austin Portugal, Charm project (PTDC/QUI-OUT/2095/2021) through the Portuguese Foundation for Science and Technology funds, The Excellence Clusters ‘Nanosystems Initiative Munich (NIM)’, and from the Free State of Bavaria through the Research Network ‘Solar Technologies go Hybrid’.Peer reviewe

Building Blocks and COFs Formed in Concert-Three-Component Synthesis of Pyrene-Fused Azaacene Covalent Organic Framework in the Bulk and as Films.

A three-component synthesis methodology is described for the formation of covalent organic frameworks (COFs) containing extended aromatics. Notably, this approach enables synthesis of the building blocks and COF along parallel reaction landscapes, on a similar timeframe. The use of fragmental building block components, namely pyrene dione diboronic acid as aggregation-inducing COF precursor and the diamines o-phenylenediamine (Ph), 2,3-diaminonaphthalene (Naph), or (1R,2R)-(+)-1,2-diphenylethylenediamine (2Ph) as extending functionalization units in conjunction with 2,3,6,7,10,11-hexahydroxytriphenylene, resulted in the formation of the corresponding pyrene-fused azaacene, i.e., Aza-COF series with full conversion of the dione moiety, long-range order, and high surface area. In addition, the novel three-component synthesis was successfully applied to produce highly crystalline, oriented thin films of the Aza-COFs with nanostructured surfaces on various substrates. The Aza-COFs exhibit light absorption maxima in the blue spectral region, and each Aza-COF presents a distinct photoluminescence profile. Transient absorption measurements of Aza-Ph- and Aza-Naph-COFs suggest ultrafast relaxation dynamics of excited-states within these COFs

Building Blocks and COFs Formed <i>in Concert</i>—Three‐Component Synthesis of Pyrene‐Fused Azaacene Covalent Organic Framework in the Bulk and as Films

AbstractA three‐component synthesis methodology is described for the formation of covalent organic frameworks (COFs) containing extended aromatics. Notably, this approach enables synthesis of the building blocks and COF along parallel reaction landscapes, on a similar timeframe. The use of fragmental building block components, namely pyrene dione diboronic acid as aggregation‐inducing COF precursor and the diamines o‐phenylenediamine (Ph), 2,3‐diaminonaphthalene (Naph), or (1R,2R)‐(+)‐1,2‐diphenylethylenediamine (2Ph) as extending functionalization units in conjunction with 2,3,6,7,10,11‐hexahydroxytriphenylene, resulted in the formation of the corresponding pyrene‐fused azaacene, i.e., Aza‐COF series with full conversion of the dione moiety, long‐range order, and high surface area. In addition, the novel three‐component synthesis was successfully applied to produce highly crystalline, oriented thin films of the Aza‐COFs with nanostructured surfaces on various substrates. The Aza‐COFs exhibit light absorption maxima in the blue spectral region, and each Aza‐COF presents a distinct photoluminescence profile. Transient absorption measurements of Aza‐Ph‐ and Aza‐Naph‐COFs suggest ultrafast relaxation dynamics of excited‐states within these COFs.</jats:p