Cleavage of the COC bond

Staude, Eberhard; Patat, F.

doi:10.1002/9780470771075.ch2

Cited by 9 publications

(2 citation statements)

References 185 publications

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“…During the nanocluster formation and concomitant hydrogenation reaction at 22 ± 0.1 °C, NMR and GC/MS analyses show that the neat acetone undergoes 95% conversion in 2 h and has reached 100% conversion in 9 h with a selectivity of 0.95 equiv (95%) 2-propanol and 0.025 equiv (=5% of the converted acetone) of diisopropyl ether (plus 0.025 equiv of water by mass balance), eq 2. The diisopropyl ether is the expected side product from the H + -catalyzed condensation of two isopropyl alcohol product molecules . Further details regarding the composite reaction stoichiometry due to the consecutive reactions of isopropyl alcohol and then diisopropyl ether formation, plus use of that balanced reaction to calculate properly the product yields, are provided in the Supporting Information.…”

Section: Resultsmentioning

confidence: 99%

Iridium(0) Nanocluster, Acid-Assisted Catalysis of Neat Acetone Hydrogenation at Room Temperature: Exceptional Activity, Catalyst Lifetime, and Selectivity at Complete Conversion

Özkâr

Finke

2005

J. Am. Chem. Soc.

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Acetone hydrogenation catalysis is important in applications such as heat pumps and fuel cells or in fulfilling the sizable demand for the product of selective acetone hydrogenation, 2-propanol. Reported herein is the discovery of a superior acetone hydrogenation catalyst--superior in terms of activity at low temperature, selectivity at complete conversion, and total catalyst lifetime. The new catalyst system consists of Ir(0)(n) nanoclusters plus HCl easily and reproducibly formed from commercially available [(1,5-COD)IrCl](2) under H(2). The resultant, room temperature, high activity, and highly selective (2/n)Ir(0)(n) plus 2HCl catalyst system hydrogenates acetone at 22 degrees C and 40 psig of H(2) pressure to 95% 2-propanol and the rest diisopropyl ether at 100% conversion with 16400 total catalytic turnovers and with an initial turnover frequency of 1.9 s(-1) at 22 degrees C. When molecular sieves are added, the catalyst system becomes even more selective and long-lived, providing the complete and selective conversion of acetone to 100% 2-propanol with 188000 total turnovers. Also reported are initial kinetic, D-labeling and other mechanistic studies, a summary section detailing the four main findings, the "green chemistry" aspects, and the current main drawback (a limited catalytic lifetime due to nanocluster precipitation) of the present invention. A review of the extensive literature of acetone hydrogenation is also tabulated as part of the Supporting Information.

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Section: Resultsmentioning

confidence: 99%

Iridium(0) Nanocluster, Acid-Assisted Catalysis of Neat Acetone Hydrogenation at Room Temperature: Exceptional Activity, Catalyst Lifetime, and Selectivity at Complete Conversion

Özkâr

Finke

2005

J. Am. Chem. Soc.

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“…In a survey of literature concerning the phenolic protective groups, the currently used methods were alkylation, benzylation and acylation (Haslam 1973, Reese 1973, Staude and Patat 1958 and the deprotective agents were protonic and Lewis acids (Haslam 1973, Reese 1973, Staude and Patat 1958, McOmie et al 1968, Teitel and O'Brien 1976, Vickery etal. 1979, Minamikawa and Brossi 1978, Brossi et al 1967, Jempty et al 1981, Prager and Tan 1967, nucleophilic and electrophilic reagents (Loubinoux et al 1980, Feutrill and Mirrington 1970, Hansson and Wickberg 1976, Caroll et al 1980, or combinations of the last two (Node et al 1980, Williard andFryhie 1980).…”

Section: Introductionmentioning

confidence: 99%

Short Note

1986

Holzforschung

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Heterogene ultrafiltrationsmembranen zur fixierung von enzymen, II

Ansorge

Staude

1983

Angew. Makromol. Chem.

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ZUSAMMENFASSUNG:Eine neue heterogene Ultrafiltrationsmembran zur kovalenten Kupplung von Enzymen wird beschrieben. Die Membranmatrix besteht aus Polysulfon, die aktive Kupplungskomponente ist ebenfalls ein Polyarylether mit entsprechendem Substituenten. Das Verhalten als reine Ultrafiltrationsmembran sowie als aktive Enzymmembran wurde untersucht. Die kovalente Immobilisierung erfolgte durch Diazotierung der aktiven Komponente. Das Enzym Dextranase ist nur in der Stiitzschicht der asymmetrischen Membran fixiert. Damit ist das Model1 eines idealen Membranbioreaktors realisiert. SUMMARY:A new heterogeneous ultrafiltration membrane for covalent immobilization of enzymes is described. The matrix of the membrane consists of polysulfone, likewise the active compound for coupling is a polyarylic ether with a suitable substituent. The behaviour as genuine ultrafiltration membrane as well as active enzymatic membrane

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Cleavage of the COC bond

Cited by 9 publications

References 185 publications

Iridium(0) Nanocluster, Acid-Assisted Catalysis of Neat Acetone Hydrogenation at Room Temperature: Exceptional Activity, Catalyst Lifetime, and Selectivity at Complete Conversion

Iridium(0) Nanocluster, Acid-Assisted Catalysis of Neat Acetone Hydrogenation at Room Temperature: Exceptional Activity, Catalyst Lifetime, and Selectivity at Complete Conversion

Short Note

Heterogene ultrafiltrationsmembranen zur fixierung von enzymen, II

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