Palladium Complexes with N-Heterocyclic Carbene Ligands As Catalysts for the Alkoxycarbonylation of Olefins

Roberts, Gina M.; Pierce, Philip J.; Woo, L. Keith

doi:10.1021/om300959f

Cited by 23 publications

(13 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In light of N‐heterocyclic carbene‐metal (NHC‐M) complexes can act as robust and viable catalysts in a broad range of reactions, various strategies have been developed for their immobilization . Among them, self‐supporting strategy may represent one of the most practical and efficient approaches .…”

Section: Fabrication Of Pomp‐nhc‐m By Direct Knitting With Different mentioning

confidence: 99%

“…In light of their robustness toward Friedel‐Crafts reaction conditions, bis‐chelating NHC‐M (Ir, Pd and Ru) complexes 4 , 5 and 6 , derived from corresponding benzimidazolium salts, were selected to fabricate POMPs via direct knitting with benzene (Figure a). Concerning the plausible impact of the ratio between the crosslinking reagent and the Lewis acid on the porous structure, surface area and catalytic activity, with bis‐NHC‐Ir complex 4a , the amounts of FeCl 3 , formaldehyde dimethyl acetal (FDA) and benzene in the knitting process were investigated for the generation of POMP‐NHC‐Ir 1a‐h ( Table 1 , entries 1–8).…”

Section: Fabrication Of Pomp‐nhc‐m By Direct Knitting With Different mentioning

confidence: 99%

See 1 more Smart Citation

Hierarchical Porous Organometallic Polymers Fabricated by Direct Knitting: Recyclable Single‐Site Catalysts with Enhanced Activity

et al. 2019

View full text Add to dashboard Cite

supported catalysts by simply knitting rigid aromatic ligands via hypercross-linking (Friedel-Crafts reactions) has recently been proposed. [13] After further postmodification/activation, several MCPPs have been successfully developed. [14][15][16][17] However, with postmodification, avoiding the problems, like low density of catalytic sites due to incomplete modification and random/ nonselective metal anchoring, can be difficult. These issues may still lead to low catalytic activity and selectivity, especially in some challenging transformations. [18] In light of N-heterocyclic carbene-metal (NHC-M) complexes can act as robust and viable catalysts in a broad range of reactions, [19][20][21][22][23][24][25][26][27][28] various strategies have been developed for their immobilization. [29,30] Among them, selfsupporting strategy may represent one of the most practical and efficient approaches. [31][32][33][34] It has to be noted that NHC ligands still have to be carefully designed and modified before selfsupporting. Alternatively, the high catalytic activities and robustness of NHC-M complexes make them perfect candidates for direct knitting. To the best of our knowledge, there are only two reported examples on MCPPs in which the NHC ligands are firstly knitted and then coordinated to active metal ions (postmodification approach). [14,15] Direct knitting of NHC-M complexes to fabricate porous organometallic polymers (POMPs) that do not require postmodification/activation is still unknown.Herein, we have designed and prepared a series of unprecedented porous organometallic polymers POMPs-NHC-M 1-3 via direct knitting three types of bis-chelating NHC-M complexes (M = Ir, Pd, and Ru, Figure 1a). Using this facile strategy, which does not require postmodification/activation, 1) the metal active sites are atomically dispersed in the hierarchical porous matrix, and 2) the intrinsic well-defined bis-chelating mode and their molecular catalytic properties are maximally retained, which allows 3) the precise design and control of the immobilized catalysts at the molecular level. The advantages of direct knitting allow the resulting POMPs-NHC-M 1-3 to behave as recyclable solid single-site catalysts and exhibit extremely high catalytic activities in both hydrogenation and dehydrogenation reactions.In light of their robustness toward Friedel-Crafts reaction conditions, bis-chelating NHC-M (Ir, Pd and Ru) complexes 4, 5 and 6, derived from corresponding benzimidazolium salts, [24,25,27] were selected to fabricate POMPs via direct knitting with benzene ( Figure 1a). Concerning the plausible impact Porous organometallic polymers (POMPs) with hierarchical pore structures, high specific surface areas, and atomically dispersed metal (Ir, Pd, Ru) centers are successfully fabricated by a facile one-pot method through direct knitting of diverse N-heterocyclic carbene metal (NHC-M) complexes. These polymers can function as recyclable solid single-site catalysts and exhibit excellent catalytic activity and selectivity in both dehydrogenat...

show abstract

Section: Fabrication Of Pomp‐nhc‐m By Direct Knitting With Different mentioning

confidence: 99%

Section: Fabrication Of Pomp‐nhc‐m By Direct Knitting With Different mentioning

confidence: 99%

Hierarchical Porous Organometallic Polymers Fabricated by Direct Knitting: Recyclable Single‐Site Catalysts with Enhanced Activity

et al. 2019

View full text Add to dashboard Cite

show abstract

“…C-C bond formation, migratory insertion and b-hydride elimination. [1][2][3][4][5][6][7][8][9][10] Steric and electronic tuning of ligands at the metal center can help to tailor activity and selectivity. Phosphine based ligands are well known to alter electronic and steric profiles of the metal and its surrounding environment, 11,12 which allows Pd(0) and Pd(II) complexes to facilitate a wide range of catalytic reactions.…”

Section: Introductionmentioning

confidence: 99%

Palladium-catalysed methoxycarbonylation of ethene with bidentate diphosphine ligands: a density functional theory study

Ahmad

Crawford

Bühl

2020

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…27 This heterogeneous catalyst exhibits excellent selectivity and higher activity than that of homogeneous catalysts under the similar conditions for the Suzuki-Miyaura cross-coupling reaction of aryl chlorides. The coordination characteristics of N-heterocyclic carbenes (NHCs) are quite similar to those of phosphines, 29 however, compared with phosphines, NHCs possess higher electrondonating ability, shorter metal-ligand bond lengths, stronger 2 | J. Name., 2012, 00, [1][2][3] This journal is © The Royal Society of Chemistry 2012 metal-ligand bonds energies and greater bond dissociation energies.…”

Section: Introductionmentioning

confidence: 99%

Palladium catalyst coordinated in knitting N-heterocyclic carbene porous polymers for efficient Suzuki–Miyaura coupling reactions

Song

et al. 2015

J. Mater. Chem. A

162

View full text Add to dashboard Cite

Three N-heterocyclic carbenes (NHCs) have been successfully integrated into the skeleton of hyper-crosslinked polymers (HCPs) via external cross-linking reaction. The structure and composition of the solid catalyst was characterized by SEM, N2 sorption, FT-IR, XPS and CP/MAS NMR. Depending on the nature of NHCs, the Brunauer-Emmer-Teller (BET) surface area of HCPs can be tuned and BET surface area as high as 1229 m 2 g -1 has been achieved. The Poly-NHC-2-Pd 2+ catalyst affords fast conversions for the Suzuki-Miyaura cross-coupling reactions of various aryl halides and arylboronic acids even at Pd loading of 0.057mol% in aqueous media. In particular, because of the substantial porosity and individual pore structure toward the entrapped Pd species, Poly-NHC-2-Pd 2+ showed outstanding stability and recyclability, which could be reused as least 5 times without significant loss of its activity. The developed microporous catalyst combined with the NHC-functionalize represent one of the most efficient heterogeneous systems for Suzuk-Miyaura cross-coupling reactions of aryl halides.

show abstract

Palladium Complexes with N-Heterocyclic Carbene Ligands As Catalysts for the Alkoxycarbonylation of Olefins

Cited by 23 publications

References 27 publications

Hierarchical Porous Organometallic Polymers Fabricated by Direct Knitting: Recyclable Single‐Site Catalysts with Enhanced Activity

Hierarchical Porous Organometallic Polymers Fabricated by Direct Knitting: Recyclable Single‐Site Catalysts with Enhanced Activity

Palladium-catalysed methoxycarbonylation of ethene with bidentate diphosphine ligands: a density functional theory study

Palladium catalyst coordinated in knitting N-heterocyclic carbene porous polymers for efficient Suzuki–Miyaura coupling reactions

Contact Info

Product

Resources

About