Online ATR-IR investigations and mechanistic understanding of the carbonylation of epoxides – the selective synthesis of lactones or polyesters from epoxides and CO

Allmendinger, Markus; Zintl, Manuela; Eberhardt, Robert; Luinstra, Gerrit A.; Molnár, F.; Rieger, Bernhard

doi:10.1016/j.jorganchem.2003.12.030

Cited by 59 publications

(48 citation statements)

References 48 publications

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“…A contact ion pair intermediate similar to 2 was suggested for the reaction of oxiranes with silylcobalt tetracarbonyls [27,29,30]. Furthermore, formation and properties of the ion pairs 2 are remarkably analogous to those of some known neutral pentacoordinated organosilicon compounds.…”

Section: Kinetics and Spectroscopic Propertiesmentioning

confidence: 78%

Formation and multinuclear magnetic resonance investigation of silylammonium tetracarbonylcobaltate contact ion pairs

Sisak

Szalontai

2006

Open Chemistry

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Section: Kinetics and Spectroscopic Propertiesmentioning

confidence: 78%

Formation and multinuclear magnetic resonance investigation of silylammonium tetracarbonylcobaltate contact ion pairs

Sisak

Szalontai

2006

Open Chemistry

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“…Thus, kinetic data as well as information about chemical conversions and reaction mechanisms can be obtained. [1][2][3][4][5][6] In the previous work, 7 a special ATR "dipper" probe was adapted to a twin-screw extruder for in-line monitoring of reactive extrusion of polymer melts. Now, we report on the use of a real-time ATR-FTIR technique to monitor different polyreactions in situ in organic solvents, which are performed under stirring in well known state-of-the-art lab reactors:…”

Section: Introductionmentioning

confidence: 99%

“…Thus, characteristic bands of monomers are decreasing (2) during the reaction, e.g., the COCl stretching vibration and CH oop deformation vibration band of 4,4Ј-dichlorodiphenyl sulfone (DC-DPS) at 1089. Furthermore, the synthesis of polysulfone is also very well detectable, e.g., by means of formation of the COOOC band at 1241 of the ether structure in the polymer.…”

mentioning

confidence: 99%

Monitoring of chemical reactions during polymer synthesis by real‐time attenuated total reflection (ATR)–FTIR spectroscopy

Sahre¹,

Schulze²,

Hoffmann³

et al. 2006

J of Applied Polymer Sci

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ABSTRACT:The present study demonstrates in situ realtime attenuated total reflection (ATR)-FTIR spectroscopy as a powerful tool for monitoring and analyzing different polymerization and polymer modification reactions. Thus, a metallocene catalyzed copolymerization of propene and 10-undecene-1-ol, a polycondensation reaction towards polysulfone, and a modification reaction of OH end groups of hyperbranched poly(urea-urethane) were investigated successfully. The interpretation of the development of FTIR spectra was carried out on the basis of typical vibration bands of chemical groups of the corresponding monomers and polymers in each case, e.g. of the CAC double bond of 10-undecene-1-ol during the copolymerization, the new COOOC group of polysulfone, and the new urethane end group of poly(urea-urethane). Kinetics prediction is also under consideration.

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“…Herein, we report the carbonylative polymerization of azetidines catalyzed by [Co(CH 3 CO)(CO) 3 P(o-tol) 3 ] (1; tol = tolyl), and the participation of the tetrahydrofuran (THF) solvent in the polymerization to give ester units in the polymer products. The use of LiI as a cocatalyst eliminates the g-lactam by-product and influences both the amount and distribution of the ester units in the polymer backbone.…”

mentioning

confidence: 99%

“…[7c] For the sterically bulkier and less nucleophilic 3, selective carbonylative enchainment occurred, as assessed by NMR spectroscopy (entries [3][4][5][6][7][8]. [11] Somewhat surprisingly, carbonylative enchainment of THF also took place and resulted in d-oxyvaleroyl ester units in the polymer products.…”

mentioning

confidence: 99%

Cobalt‐Catalyzed Carbonylative Copolymerization of N‐Alkylazetidines and Tetrahydrofuran

Liu

2005

Angew Chem Int Ed

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The metal-catalyzed carbonylative polymerization of heterocycles (COPH) has received much attention in the last few years as a novel method for the synthesis of polyamides and polyesters. [1][2][3][4][5][6][7] Motivation for these research activities is the practical demand for polymers with heteroatom-containing backbones that are susceptible to hydrolytic and/or enzymatic attack in biological or ecological environments. [8,9] We are interested in the development of COPH using an approach based on single-site catalysts, under the idea that well-defined molecular catalysts would allow rational design and control of the chemical composition, molecular weight, and microstructure of the polymer product.Herein, we report the carbonylative polymerization of azetidines catalyzed by [Co(CH 3 CO)(CO) 3 P(o-tol) 3 ] (1; tol = tolyl), and the participation of the tetrahydrofuran (THF) solvent in the polymerization to give ester units in the polymer products. The use of LiI as a cocatalyst eliminates the g-lactam by-product and influences both the amount and distribution of the ester units in the polymer backbone. The well-controlled distribution of the ester units and the living character of the polymerization have allowed the synthesis of polymers with alternating amide blocks and ester segments, which undergo two-stage degradation. [10] Herein, N-n-butylazetidine (2) and Nisobutylazetidine (3) are used as representative monomers. The polymerization was carried out in THF under CO (1000 psi) at 60-80 8C (Table 1). For 2, in addition to the major carbonylative enchainment that resulted in the amide units, a simple ring-opening enchainment without carbonylation was also observed, which resulted in amine units in the polymer chain (entries 1 and 2).[7c] For the sterically bulkier and less nucleophilic 3, selective carbonylative enchainment occurred, as assessed by NMR spectroscopy (entries 3-8).[11] Somewhat surprisingly, carbonylative enchainment of THF also took place and resulted in d-oxyvaleroyl ester units in the polymer products.[12] Thus, the reactions of 2 and 3 in THF produced poly(amide-co-amine-co-ester)s (PAAEs) and poly(amideco-ester)s (PAEs), respectively [Table 1, Eqs. (1) and (2)].The extent of THF carbonylative enchainment differed when 2 and 3 were used as the monomer: twofold as many ester units were incorporated with 3 than with 2 (entries 1 vs. 3, and 2 vs. 4).The ester abundance, which is defined as the number of ester units divided by the total number of all monomer units, was also a function of the initial monomer-to-catalyst ratio. Higher monomer loadings resulted in a lower degree of ester incorporation (entries 3-8), which suggests that the reaction of THF was favored when the azetidine concentration was low. Directly monitoring the amide and ester growth by in situ IR spectroscopy confirmed that the ester abundance in the Table 1: Carbonylative polymerization of azetidine and THF (CO pressure 1000 psi). [a] Entry THF[mL]Azetidine Azetidine/1 (molar ratio)Cocatalyst Selectivity [b] Ester abun...

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Online ATR-IR investigations and mechanistic understanding of the carbonylation of epoxides – the selective synthesis of lactones or polyesters from epoxides and CO

Cited by 59 publications

References 48 publications

Formation and multinuclear magnetic resonance investigation of silylammonium tetracarbonylcobaltate contact ion pairs

Formation and multinuclear magnetic resonance investigation of silylammonium tetracarbonylcobaltate contact ion pairs

Monitoring of chemical reactions during polymer synthesis by real‐time attenuated total reflection (ATR)–FTIR spectroscopy

Cobalt‐Catalyzed Carbonylative Copolymerization of N‐Alkylazetidines and Tetrahydrofuran

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