New Phosphorus Ligands for the Rhodium-Catalyzed Isomerization/Hydroformylation of Internal Octenes

Selent, Detlef; Hess, Dieter; Wiese, Klaus‐Diether; Röttger, Dirk; Kunze, Christine; Börner, Armin

doi:10.1002/1521-3773(20010504)40:9<1696::aid-anie16960>3.0.co;2-2

Cited by 91 publications

(28 citation statements)

References 7 publications

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“…Particularly successful have been so-called wide bite-angle diphosphine ligands as well as (di)phosphites, phosphonites and pyrrolylphosphines, particularly for unfunctionalized (internal) alkenes. [75][76][77][78][79][80] Typical unwanted side-reactions include, besides the formation of branched products, isomerization or hydrogenation of the alkene double bond, aldol-condensations and the formation of alcohols (hydroxycarbonylation). During the reductive amination, secondary reactions include the conversion of initial and desired primary amine to secondary/ tertiary counterparts.…”

Section: Hydroaminomethylationmentioning

confidence: 99%

Advances in selective activation and application of ammonia in homogeneous catalysis

Vlugt

2010

Chem. Soc. Rev.

212

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Section: Hydroaminomethylationmentioning

confidence: 99%

Advances in selective activation and application of ammonia in homogeneous catalysis

Vlugt

2010

Chem. Soc. Rev.

212

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“…On this occasion, the corresponding chlorophosphite from the tropos diol was formed in THF at low temperature, minimizing the formation of a byproduct, the unsymmetrical phosphite containing two tropos diol fragments ( 31 P{ 1 H} NMR, ca. 140 ppm) that this diol is prone to form at higher temperatures . The chlorophosphite was reacted directly with precursor 6a or 6b in the presence of DABCO to give the desired ligands 9a and 9b .…”

Section: Resultsmentioning

confidence: 99%

Effect of Ligand Backbone on the Selectivity and Stability of Rhodium Hydroformylation Catalysts Derived from Phospholane-Phosphites

et al. 2021

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A study on how ligand backbone structure has an impact on selectivity, rate, and catalyst stability of hydroformylation catalysts was prompted by some longer-term stability issues being discovered for a phospholane-phosphite with a [−CH 2 O−] backbone. A series of phospholane-phosphite ligands were synthesized. Catalysts made in situ from these ligands and [Rh(acac)(CO) 2 ] were found to give iso-butanal selectivities up to 75% at temperatures between 75 and 105 °C: the latter being a benchmark for iso-selectivity in reactions conducted at industrially meaningful temperatures. A racemic rhodium complex of a bidentate phospholane-phosphite from a tropos-biphenol with an extended backbone showed unusually high stability at high temperatures, combined with even better iso-selectivity in propene hydroformylation relative to the original complex. A related ligand with an electron-withdrawing group maintained the unusually high stability and improved activity. Characterization of the precatalysts of type [RhH(CO) 2 (L)] was accomplished using in situ HPIR spectroscopy and backed up by density functional theory calculations (B3PW91-D3 level) and by NMR studies; the latter showed that the variation of the backbone also had a pronounced impact on the precatalyst structure. A key finding is that it is now possible to prepare phospholane-phosphite ligands that deliver high iso-butanal selectivity and that show no signs of degradation after several days even above typical reaction temperatures. In one stability test, several kilograms of aldehydes were produced with TOF and selectivity being consistent over several days.

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“…values up to 112 (mol aldehyde)(mol Rh) À1 h À1 ) observed were explained by the decreased phosphine basicity and the wider natural bite angles (b 1208) of the ligands. Recently, Börner and co-workers [49] have reported on the use of p-acidic bidentate ligands based on a O-acylphosphite moiety for the Rh-catalyzed hydroformylation of internal octenes. High activities (t.o.f.…”

Section: (E)-oct-2-enementioning

confidence: 99%

Xantphite: A New Family of Ligands for Catalysis. Applications in the Hydroformylation of Alkenes

Dieleman

Kamer

Reek

et al. 2001

HCA

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Dedicated to the memory of Professor Luigi M. VenanziThe novel bulky diphosphite (P P) ligands (3 and 4) based on the 2, 7,9,9-tetramethyl-9H-xanthene-4,5diol (2) backbone were investigated in the Rh-catalyzed hydroformylation of oct-1-ene, styrene, and (E)-oct-2ene. These diphosphites gave rise to very active and selective catalysts for the hydroformylation of oct-1-ene to nonanal with average rates b 10000 (mol aldehyde)(mol Rh) À1 h À1 (P(CO/H 2 ) 20 bar, T 808, [Rh] 1 mm) and maximum selectivities of 79% for the linear product. Relatively high selectivities towards the linear aldehyde (up to 70%, linear/branched up to 2.3) but very high activities (up to 39000 (mol aldehyde)(mol Rh) À1 h À1 ) were observed for the hydroformylation of styrene in the presence of these bidentate ligands (P(CO/ H 2 ) 2 ± 10 bar, T 1208, [Rh] 0.2 mm). Remarkable activities (up to 980 (mol aldehyde)(mol Rh) À1 h À1 ) were achieved with these diphosphites for the hydroformylation of (E)-oct-2-ene with selectivities for the linear product of 74% (l/b up to 2.8, P(CO/H 2 ) 2 bar, T 1208, [Rh] 1 mm). A detailed study of the solution structure of the catalyst under catalytic conditions was performed by NMR and high-pressure FT-IR. The spectroscopic data revealed that under hydroformylation conditions, the bidentate ligands rapidly formed stable, well-defined catalysts with the structure [RhH(CO) 2 (P P)]. All the ligands showed a preference for an equatorial-apical (ea) coordination mode in the trigonal bipyramidal Rh-complexes, indicating that a bisequatorial (ee) coordination is not a prerequisite for highly selective catalysts.

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New Phosphorus Ligands for the Rhodium-Catalyzed Isomerization/Hydroformylation of Internal Octenes

Cited by 91 publications

References 7 publications

Advances in selective activation and application of ammonia in homogeneous catalysis

Advances in selective activation and application of ammonia in homogeneous catalysis

Effect of Ligand Backbone on the Selectivity and Stability of Rhodium Hydroformylation Catalysts Derived from Phospholane-Phosphites

Xantphite: A New Family of Ligands for Catalysis. Applications in the Hydroformylation of Alkenes

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