Steric activation of chelate catalysts: efficient polyketone catalysts based on four-membered palladium(ii) diphosphine chelates

Dossett, Stephen J.; Gillon, Amy L.; Orpen, A. Guy; Fleming, James S.; Pringle, Paul G.; Wass, Duncan F.; Jones, Matthew D.

doi:10.1039/b010063n

Cited by 99 publications

(56 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The anion cis-[Rh(CO) 2 I 2 ] À was found to be the initial catalytically active species [3]. As the rate-determining step of the catalytic cycle is the oxidative addition of MeI to cis-[Rh(CO) 2 I 2 ] À [4], electron enrichment at the metal center is expected to facilitate this step and to improve the rate of AcOH formation. Consequently, square-planar rhodium(I) complexes with ligands that increase the electron density at the Rh-atom have been developed and studied as catalysts; they give better or at least comparable activities than the original Monsanto catalyst [5 ± 8].…”

mentioning

confidence: 99%

Square‐Planar Carbonylchlororhodium(I) Complexes Containing trans‐Spanning Diphosphine Ligands as Catalysts for the Carbonylation of Methanol

Burger

Therrien

Süß‐Fink

2005

Helvetica Chimica Acta

View full text Add to dashboard Cite

Dedicated to Professor AndreÂ Merbach on the occasion of this 65th birthdayThe rhodium(I) complexes trans-[Rh(diphos)(CO)Cl] 7 (diphos pbpb), 8 (diphos nbpb), and 9 (diphos cbpb) were synthesized (Scheme 4) and used as catalysts for the carbonylation of MeOH to AcOH (Scheme 1). The trans coordination imposed by the rigid C-spacer framework of the diphos ligands pbpb, nbpb, and cbpb, demonstrated by 31 P-NMR and IR spectroscopy of 7 ± 9 and unambiguously confirmed by singlecrystal X-ray structure analysis of 7, improved the thermal stability of the rhodium(I) system under carbonylation conditions and, hence, the catalytic performance of the complexes. For the catalytic carbonylation of MeOH, the active catalyst could be prepared in situ from the mixture of [Rh(CO) 2 Cl] 2 and the corresponding diphos ligand pbpb, nbpb, or cbpb, giving the same results as carbonylation in the presence of the isolated complexes 7, 8 or 9 (see Table). The highest activity was observed for complex 7 (or the mixture [Rh(CO) 2 Cl] 2 / pbpb, the catalytic turnover number (TON) being 950 after 15 min (1708, 22 bar). The anion cis-[Rh(CO) 2 I 2 ] À was found to be the initial catalytically active species [3]. As the rate-determining step of the catalytic cycle is the oxidative addition of MeI to cis-[Rh(CO) 2 I 2 ] À [4], electron enrichment at the metal center is expected to facilitate this step and to improve the rate of AcOH formation. Consequently, square-planar rhodium(I) complexes with ligands that increase the electron density at the Rh-atom have been developed and studied as catalysts; they give better or at least comparable activities than the original Monsanto catalyst [5 ± 8]. Introduction. ± The carbonylation of MeOH to generate AcOH is one of the most important homogeneously catalyzed industrial processes [1] (Scheme 1). The production of AcOH by the

show abstract

mentioning

confidence: 99%

Square‐Planar Carbonylchlororhodium(I) Complexes Containing trans‐Spanning Diphosphine Ligands as Catalysts for the Carbonylation of Methanol

Burger

Therrien

Süß‐Fink

2005

Helvetica Chimica Acta

View full text Add to dashboard Cite

show abstract

“…The stepwise formation of 4 is best monitored by 31 P{ 1 1 H} signal is observed, a singlet appears at 36.6 ppm. The second reaction step corresponds to the formation of six-membered chelate rings through coordination of the sulfur atoms to the rutheniums.…”

Section: Resultsmentioning

confidence: 99%

“…The product was isolated from the fourth fraction, giving 2 as a white solid (300 mg, 0.44 mmol; 27%). 1 …”

Section: Preparation Of Dppan (2)mentioning

confidence: 99%

“…After 3 days, 5 was obtained by slow evaporation of the chloroform solution. 1 [10]. The refinement and all further calculations were carried out using SH ELXL S HELXL-97 [11].…”

Section: Preparation Of [Ruclmentioning

confidence: 99%

“…Phosphine ligands have been intensively used in coordination chemistry because of their electron-donating power [1]. Diphosphine ligands have received particular attention, because in general they form more stable complexes than their non-chelating phosphine analogues under the harsh reaction conditions required for catalysis.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

New dinuclear arene ruthenium complexes with P,S- or P,O-chelating ligands

Burger

Therrien

Süß‐Fink

2004

Inorganica Chimica Acta

View full text Add to dashboard Cite

Two equivalents of 2-diphenylphosphinobenzoic acid react with 1,2-ethanedithiol and 1,8-diaminonaphthalene under peptidic coupling conditions to give the new ligands 1,2-bis-S-[2 0 -(diphenylphosphino)benzoyl]dithioethane (dppte) (1) and 1,2-bis-N-[2 0 -(diphenylphosphino)benzoyl]diaminonaphthalene (dppan) (2), respectively. 1 and 2 have been characterised by mass spectrometry, elemental analysis, NMR, IR spectroscopy, and by single-crystal X-ray structure analysis. 2 is easily oxidised by air to give the monophosphine oxide derivatives (3). Single-crystal X-ray structure analysis of 3 shows an intramolecular hydrogen bond between an amido and the phosphoryl oxygen atom. Compounds 1 and 2 react with [RuCl 2 (g 6 -p-cymene)] 2 to give the dinuclear complexes [RuCl(g 6 -p-cymene)(dppte)RuCl(g 6 -p-cymene)] 2þ (4) and [RuCl(g 6 -p-cymene)(dppan)RuCl(g 6 -p-cymene)] 2þ (5). As determined by single-crystal X-ray structure analysis, 4 and 5 adopt different coordination modes to the ruthenium atoms. In 4 the symmetric dppte ligand is P ; S coordinated to the ruthenium atom, whereas in 5 the dppan ligand prefers a P ; O coordination mode.

show abstract

Late Transition Metal–Catalyzed Co‐ and Terpolymerization of α‐Olefins with Carbon Monoxide–Polyketones: Synthesis and Modification

Anselment

Zintl

Leute

et al. 2010

Handbook of Transition Metal Polymerization Catalysts

View full text Add to dashboard Cite

Steric activation of chelate catalysts: efficient polyketone catalysts based on four-membered palladium(ii) diphosphine chelates

Cited by 99 publications

References 6 publications

Square‐Planar Carbonylchlororhodium(I) Complexes Containing trans‐Spanning Diphosphine Ligands as Catalysts for the Carbonylation of Methanol

Square‐Planar Carbonylchlororhodium(I) Complexes Containing trans‐Spanning Diphosphine Ligands as Catalysts for the Carbonylation of Methanol

New dinuclear arene ruthenium complexes with P,S- or P,O-chelating ligands

Late Transition Metal–Catalyzed Co‐ and Terpolymerization of α‐Olefins with Carbon Monoxide–Polyketones: Synthesis and Modification

Contact Info

Product

Resources

About