Multifunctional Single‐Site Catalysts for Alkoxycarbonylation of Terminal Alkynes

Abstract

A multifunctional copolymer (PyPPh2 -SO3 H@porous organic polymers, POPs) was prepared by combining acidic groups and heterogeneous P,N ligands through the copolymerization of vinyl-functionalized 2-pyridyldiphenylphosphine (2-PyPPh2 ) and p-styrene sulfonic acid under solvothermal conditions. The morphology and chemical structure of the copolymer were evaluated using a series of characterization techniques. Compared with traditional homogeneous Pd(OAc)2 /2-PyPPh2 / p-toluenesulfonic acid catalyst, the copolymer supported palladium catalyst (Pd-PyPPh2 -SO3 H@POPs) exhibited higher activity for alkoxycarbonylation of terminal alkynes under the same conditions. This phenomenon could be attributed to the synergistic effect between the single-site Pd centers, 2-PyPPh2 ligands, and SO3 H groups, the outstanding swelling properties as well as the high enrichment of the reactant concentration by the porous catalyst. In addition, the catalyst could be reused at least 4 times without any apparent loss of activity. The excellent catalytic reactivity and good recycling properties make it an attractive catalyst for industrial applications. This work paves the way for advanced multifunctional porous organic polymers as a new type of platform for heterogeneous catalysis in the future.

Iridium Supported on Phosphorus‐Doped Porous Organic Polymers: Active and Recyclable Catalyst for Acceptorless Dehydrogenation and Borrowing Hydrogen Reaction

“…This observation is consistent with the proposed structure of 1 a. [10] We also found peaks of binding energy at 64.7 eV and 61.9 eV, belonging to Ir 3 + , which are consistent with the existing literature data. [19] According to quantitative elemental analysis and calculations, the load of iridium is about 4.4% (Table S1).…”

“…More detailed data of XPS and analysis could be found in the SI. [10] We also found peaks of binding energy at 64.7 eV and 61.9 eV, belonging to Ir 3 + , which are consistent with the existing literature data. After fitting the P spectral peaks, we found peaks at 132.18 eV, which belong to PÀ C bonds, and on the other hand the peaks at 130.75 eV, which belong to PÀ Ir bonds.…”

“…In the recent years, a series of metals that were supported on POPÀ PPh 3 or other derivatives, have been reported, [3] including rhodium, [4] platinum, [5] cobalt, [6] iron, [7] molybdenum, [7] zinc [8] and gold. [10] In 2017, Ding and Yan demonstrated that a series of zinc salts and triphenylphosphine integrated porous organic polymers which contained multifunctional sites and were able to show high catalytic performance in the cycloaddition of CO 2 with epoxides. The HC-TVP was successfully ionized when treated with hydrogen iodide to form an ionic porous polymer.…”

“…[9] In 2016, Ding and coworkers synthesized a multifunctional copolymer (PyPPh 2 À SO 3 H@porous organic polymers, POPs) through the copolymerization reaction under solvothermal conditions and the corresponding copolymersupported PdÀ PyPPh 2 À SO 3 H@POPs catalyst showed higher activities. [10] In 2017, Ding and Yan demonstrated that a series of zinc salts and triphenylphosphine integrated porous organic polymers which contained multifunctional sites and were able to show high catalytic performance in the cycloaddition of CO 2 with epoxides. [8] In 2017, Zhan and Ding developed a P-doped porous organic polymer and employed it as support and ligand to achieve a novel Pd complex which has shown high efficiency in catalyzing hydrogenation reactions and resulted in high chemoselectivity.…”

Dual‐Ionically Bound Single‐Site Rhodium on Porous Ionic Polymer Rivals Commercial Methanol Carbonylation Catalysts

“…In some other cases, metal nanoparticles were also observed, highlighting the importance of structural matching of metals with ligands of the carriers. Additionally, single‐site metal may transform into nanoparticles when the metal loading reaches a threshold value . A better strategy to further strengthen the metal–support interactions is by introducing ionic bonds to immobilize the active species on the carrier as described in Section .…”