Chiral 1,2‐Disubstituted Ferrocene Diphosphines for Asymmetric Catalysis

Blaser, Hans‐Ulrich; Chen, Weiping; Camponovo, Francesco; Togni, Antonio

doi:10.1002/9780470985663.ch6

Cited by 27 publications

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“…Indeed, attempts to modify phosphinoferrocene donors by changing their phosphine substituents are well documented. However, systematic structural variations have mostly concerned dppf analogues, [Fe(η 5 -C 5 H 4 PR 2 ) 2 ] (dppf = 1,1′-bis(diphenylphosphino)ferrocene), and chiral donors of the Josiphos family introduced by Togni et al…”

Section: Introductionmentioning

confidence: 99%

Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

et al. 2017

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The stereoelectronic influence of phosphine substituents on the coordination and catalytic properties of phosphinoferrocene carboxamides was studied for the model compounds R2PfcCONHMe (1a–d), where fc = ferrocene-1,1′-diyl and R = i-Pr (a), t-Bu (b), cyclohexyl (Cy; c), Ph (d), using experimental and DFT-computed parameters. The electronic parameters were examined via 1 J SeP coupling constants determined for R2P(Se)fcCONHMe (6a–d) and CO stretching frequencies of the Rh(I) complexes trans-[RhCl(CO)(1-κP)2] (7a–d); the steric properties of 1a–d were assessed through Tolman’s ligand cone angles (θ) and solid angles (Ω). Generally, a very good agreement between the calculated and experimental values was observed. Whereas the donor ability of the amidophosphines was found to increase from 1d through 1a,c to 1b, the trends in steric demand suggested by the two parameters differed, reflecting the different spatial properties of the phosphine substituents. In situ NMR studies and catalytic tests on the Suzuki–Miyaura cross-coupling of 4-bromoanisole with a bicyclic 4-tolylborate to give 4-methyl-4′-methoxybiphenyl using [Pd(η2:η2-cod)(η2-ma)] (cod = cycloocta-1,5-diene, ma = maleic anhydride) as a Pd(0) precursor revealed that different Pd-1 species (precatalysts) were formed from different ligands and participated in the reaction. Specifically, the bulky and electron-rich donor 1b favored the formation of [Pd(1b)(ma)], while the remaining ligands provided the corresponding bis-phosphine complexes [Pd(1)2(ma)]. The best results in terms of catalyst longevity and efficacy were observed for ligands 1a,c.

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Section: Introductionmentioning

confidence: 99%

Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

et al. 2017

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“…1,1′-Bis(diphenylphosphino)ferrocene (dppf) is the bidentate phosphine with a metallocene backbone that has been studied the most, particularly as a ligand in catalytic systems . There are many different types of ligands that are closely related to dppf, but the most common are ones in which the R groups on the phosphorus atoms are altered (Figure ).…”

Section: Introductionmentioning

confidence: 99%

Structural, Computational, and Spectroscopic Investigation of [Pd(κ³-1,1′-bis(di-tert-butylphosphino)ferrocenediyl)X]⁺(X = Cl, Br, I) Compounds

et al. 2016

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The reaction of [Pd(dtbpf)Cl 2 ] (dtbpf = 1,1′-bis(di-tertbutylphosphino)ferrocene) with sodium bromide yields [Pd(dtbpf)Br][Br], which displays an interaction between the iron and palladium atoms. The structure of this compound has been obtained and is compared to those of the previously reported [Pd(dtbpf)X] + (X = Cl, I) analogues. Similar to [Pd(dtbpf)Cl] + , [Pd(dtbpf)Br] + appears to undergo a solid-state isomerization at low temperature to a species in which the Fe−Pd interaction is disrupted. In addition to 1 H and 31 P{ 1 H} NMR and visible spectroscopy, the [Pd(dtbpf)X] + (X = Cl, Br) compounds were also characterized by zero-field 57 Fe Mossbauer spectroscopy. DFT calculations on [Pd(dtbpf)-X] + (X = Cl, Br, I) show that the Fe−Pd interaction is weak and noncovalent and that the strength of the interaction decreases as the halide becomes larger. A related trend is noted in the potential at which oxidation of the iron center occurs; the larger the halide, the less positive the potential at which oxidation occurs. Finally, the catalytic activity of [Pd(dtbpf)X] + (X = Cl, Br, I) in the arylation of an aromatic ketone was examined and compared to the activity of [Pd(dtbpf)Cl 2 ].

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“…Chiral cyclopentadienide (Cp) metal complexes have gained broad interest mainly due to applications in stereoselective reactions . During the past decades, five principle strategies were developed to synthesize such compounds: (a) the use of chiral (auxiliary) ligands such as phosphines in addition to a Cp ligand, (b) the generation of chiral metal centers, (c) the substitution of a Cp hydrogen atom against a chiral side chain, (d) the generation of a metal complex possessing planar chirality mostly realized with ferrocenes by the introduction of two different substituents in the 1- and 2-position of the Cp ligand, and (e) the use of Cp derivatives possessing helical chirality or introducing it when bound to a metal site .…”

Section: Introductionmentioning

confidence: 99%

Complexes of Platinum Group Elements Containing the Intrinsically Chiral Cyclopentadienide Ligand (Cp^C)⁻¹

et al. 2020

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Cyclopentadienide derivatives possessing intrinsic helical chirality have only rarely been published in the past. The ligand Cp C H, which is well-accessible from inexpensive dibenzosuberenone, is paradigm for such a ligand. Here, the synthesis as well as the spectroscopic and structural characterization of a series of platinum group metal complexes containing this ligand are presented. While alkaline metal salts of Cp C H failed in transferring the (Cp C ) −1 unit to this type of metal sites, (Cp C )Tl turned out to be an excellent precursor for the synthesis of ruthenium ([(η 5 -Cp C )Ru(η 6 -arene)]PF 6 , [(η 5 -Cp C )Ru(NCCH 3 ) 3 )]PF 6 ), rhodium ((η 5 -Cp C )Rh(η 4 -COD)), and iridium ((η 5 -Cp C )Ir(η 4 -COD), [(η 5 -Cp*)Ir(η 5 -Cp C )]PF 6 ) complexes with Cp C ligands. EXSY NMR studies were carried out to obtain a deeper insight into the ligand dynamics of Cp C complexes.

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Chiral 1,2‐Disubstituted Ferrocene Diphosphines for Asymmetric Catalysis

Cited by 27 publications

References 0 publications

Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

Structural, Computational, and Spectroscopic Investigation of [Pd(κ³-1,1′-bis(di-tert-butylphosphino)ferrocenediyl)X]⁺(X = Cl, Br, I) Compounds

Complexes of Platinum Group Elements Containing the Intrinsically Chiral Cyclopentadienide Ligand (Cp^C)⁻¹

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Chiral 1,2‐Disubstituted Ferrocene Diphosphines for Asymmetric Catalysis

Cited by 27 publications

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Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

Probing the Influence of Phosphine Substituents on the Donor and Catalytic Properties of Phosphinoferrocene Carboxamides: A Combined Experimental and Theoretical Study

Structural, Computational, and Spectroscopic Investigation of [Pd(κ3-1,1′-bis(di-tert-butylphosphino)ferrocenediyl)X]+(X = Cl, Br, I) Compounds

Complexes of Platinum Group Elements Containing the Intrinsically Chiral Cyclopentadienide Ligand (CpC)−1

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Structural, Computational, and Spectroscopic Investigation of [Pd(κ³-1,1′-bis(di-tert-butylphosphino)ferrocenediyl)X]⁺(X = Cl, Br, I) Compounds

Complexes of Platinum Group Elements Containing the Intrinsically Chiral Cyclopentadienide Ligand (Cp^C)⁻¹