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We report for the first time a novel support of polyetheretherketone fiber for the synthesis of recyclable N-heterocyclic carbene (NHC) catalysts. The fiber catalysts were verified in nucleophilic acylation of fluorobenzenes with superior catalytic activities, and successfully recycled by a tiny pair of tweezers over 21 cycles with minimal loss of performance. [ABSTRACT FROM AUTHOR]

Herein, a newly designed fiber-supported iron catalyst was successfully synthesized by rooting diamine ligands into the surface layer of commercially available polyacrylonitrile fiber and then utilizing the diamine groups to immobilize Fe(iii) ions for heterogeneous catalytic ring-opening reactions. The resulting materials were characterized and observed in detail by elemental analysis, mechanical properties, FTIR spectroscopy and morphology during both the preparation and the utilization processes. Moreover, the fiber catalyst was used in the spinning basket reactor-mediated ring-opening of various epoxides by a series of alcohols under mild reaction conditions, giving good to quantitative yields of the corresponding β-alkoxy alcohols. In addition, the fiber catalyst in the impellers of the agitation system was shown to be reusable multiple times without leaching of the Fe(iii) ions, and when stored on the shelf remained equally active for at least three months. Furthermore, the catalytic system was convenient and effective for scaling-up experiments and thereby has prospects in industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fibrous superbase catalyst for organic conversions in continuous-flow processing. • Powerful combination of support and catalyst for prominent application performance. • Highly catalytic activity and general applicability for the mediated reactions. • Superior stability and strong practicality for efficient scale-up procedure. The development of clean catalytic technologies in continuous-flow processing for efficient organic conversions has a positive influence on the fine chemicals and pharmaceutical manufacturing. Herein, the commonly used organic superbase 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) was immobilized on the commercially available ultra-high strength textile fiber polyetheretherketone (PEEK) to report a polymer-supported basic catalyst (PEEK-TBD) for three types of organic conversions in cleaner continuous-flow processing. The fiber catalyst was prepared through an improvement strategy and verified as a heterogeneous fibrous superbase catalyst in the microtubule reactor to mediate the Knoevenagel condensation-cyclization between salicylaldehydes and activated nitriles for the synthesis of iminocoumarins in ethanol (10 samples, yields 91–97%) after turning the flow rate, substrate concentration, and catalyst padding quantity, additionally, PEEK-TBD was also effective for the cyanosilylation of carbonyl compounds for the synthesis of cyanogen compounds in acetonitrile, as well as the substitution reaction of aniline and carbonate for the synthesis of N , N '-substituted urea in toluene in continuous-flow processing. Moreover, the resulting fiber samples were characterized in detail by sorts of analytical methods and techniques to further confirm the dependability of this methodology, and the clean and valid gram-scalable procedure of PEEK-TBD in continuous-flow processing has extensive application prospects on the chemical productions. [ABSTRACT FROM AUTHOR]

• Targeted design, convenient synthesis and detailed characterization of the catalyst. • Cooperative catalysis, mild conditions and general applicability for CO 2 utilization. • Prominent recyclability, simple separation and efficient gram-scale processes. Herein, a novel fiber-supported N-heterocyclic carbene (NHC) precursor and copper(I) composite (EIMBr-PANF TA @CuI), capable of acting as a cooperative catalyst for cleaner carboxylation of terminal alkynes from CO 2 , is presented. The EIMBr-PANF TA @CuI was synthesized systematically, and the resulting fiber samples from preparation and utilization processes were characterized detailedly. Moreover, the unique fiber-supported composite structure as a cooperative catalyst exhibited the synergistic effect on the activation of CO 2 and terminal alkyne, which corporately contributed to the high catalytic performance on carboxylation for producing a series of alkyl 2-alkynoates in acetonitrile under ambient conditions. Furthermore, EIMBr-PANF TA @CuI was stable to air and moisture, and could be easily recovered with a tiny pair of tweezers and recycled with good activity over 10 runs. In addition, this protocol was convenient and effective for gram-scale experiments and thereby was prospective in practical applications. [ABSTRACT FROM AUTHOR]

• Anion specie and chain-length effects on the fiber-supported Ni(II) complex catalyst. • Facile synthesis, detailed characterization and good recyclability of the catalyst. • Highly catalytic activity and general applicability for the A3-coupling. • Simple separation and efficient scale-up procedures in the spinning basket reactor. Herein, a new series of polymer-supported Ni(II) complex catalysts with different ligand chain lengths grafted on the fiber for one-pot multicomponent A3-coupling reactions, is reported. The fiber catalysts were prepared conveniently from commercially available polyacrylonitrile fiber via a simple two-step procedure by polyamine-amination and nickel-chelation in water respectively, and the resulting materials from the modification and utilization processes were characterized detailedly by morphology, mechanical property, elemental analysis, FTIR spectroscopy and SEM. Moreover, the fiber-supported Ni(II) complex catalysts with chlorine anion and longer chain ligands exerted higher efficiency than short chains, and the mediated reactions showed broad applicability and proceeded smoothly to afford a number of substituted propargylamines under mild conditions. Furthermore, the newly developed fiber catalyst held high strength, good flexibility and exhibited excellent stability and recyclability (over 15 cycles), and the procedure was scalable on a gram scale in a concise spinning basket reactor with good industrialization prospect. [ABSTRACT FROM AUTHOR]