The Catalyzed Cleavage of Diacetone Alcohol and Other Ketols and Unsaturated Ketones<sup>1</sup>

McAllister, S. H.; Bouton, C. M.

doi:10.1021/ja01868a090

Cited by 32 publications

(25 citation statements)

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“…Ber . Daraufhin wurde durch radikalische Chlorierung von 2-Octanon 3-Chlor-2-octanon dargestellt 16), dieses zum entsprechenden Acyloin verseift 17) und rnit 3-Oxoadipinsauredimethylester umgesetzt.…”

Section: Nmr-spektrenunclassified

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Spiteller

Hoyer

1980

Chem. Ber.

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Aus 10 1 Harn wurde durch Kombination verschiedener chromatographischer Verfahren 1 mg Pentylurofuransaure, eine Dicarbonsaure C14H2005, isoliert. Ihr kommt nach spektroskopischer Untersuchung in Kombination mit Mikroabbaureaktionen die Konstitution 3-Carboxy-4-methyl-5-pentyl-2-furanpropansaure (la) zu, die durch Synthese gesichert wurde. Die Pentylurofuransaure kommt nicht nur im Harn (0.5-2 mg/24 h), sondern auch im Blut vor. Begleitverbindungen unterscheiden sich von ihr nur durch den Bau der Seitenkette in Stellung 5. Urofuranic Acids -a Hitherto Unknown Class of Metabolic CompoundsBy a combination of chromatographic methods 1 mg of pentylurofuranic acid, a dicarboxylic acid CI4H2,,O5, was isolated from 10 1 urine. According to spectroscopic measurements in combination with reactions in microscale its structure is 3-carboxy-4-methyl-5-pentyl-2-furanpropanoic acid (la). This was confirmed by synthesis. Pentylurofuranic acid does not only occur in urine, but also in blood. Accompanying compounds differ only in the construction of the side chain in position 5 .Die Entwicklung potenter Trennmethoden in Verbindung mit spektroskopischen Verfahren hat in den letzten beiden Jahrzehnten wesentlich zur Isolierung und Konstitutionsaufilarung zahlreicher niedermolekularer neuer Pflanzeninhaltsstoffe beigetragen. Sehr vie1 weniger wurden diese Untersuchungen bei der Analyse biologischer Flussigkeiten verwendet -offenbar in der Annahme, dal3 in ihnen die meisten niedermolekularen Stoffe bereits bekannt sind.Erst in jungster Zeit ist durch die Anwendung der Glaskapillargaschromatographie in Kombination mit der Massenspektrometrie klargeworden, dalj unser Wissen iiber die Inhaltsstoffe biologischer Flussigkeiten sehr begrenzt ist'P2). In dieser Arbeit werden am Beispiel der Konstitutionsauf'klarung der bisher unbekannten Urofuransauren prinzipielle Wege zur Identifizierung solcher Spurenstoffe beschrieben. Isolierung und Charakterisierung der UrofuransaurenDurch Adsorption an XAD-Harzen konnen die sauren Bestandteile des Harns von salzartigen Bestandteilen abgetrennt und durch Waschen mit Methanol wieder eluiert werden3). Unterwirft man die mit Diazomethan erhaltlichen Methylester einer gaschro-

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Section: Nmr-spektrenunclassified

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Spiteller

Hoyer

1980

Chem. Ber.

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“…The significant amounts of fission products that were observed with the resins under diffusion control made possible the measurement of selectivities over a wide range of conversions to identify pathways in the reaction network. Cleavage products equivalent to those observed here were observed in other aldol condensations and several pathways were formulated, a decomposition of the aldol, or a protolytic or hydrolytic cleavage of the condensation product . To distinguish these possibilities, the Pathway A products were analyzed with one of the benchmark catalysts, Amberlyst 36.…”

Section: Resultsmentioning

confidence: 77%

Section: Introductionmentioning

confidence: 99%

“…Ap otentially useful side reactioni st he fission of the aldol reactionp roducts which is known to occur during the conversion of acetone to diacetone alcohol and mesityloxide, yielding isobutene and acetic acid. First observed long ago, [7,8] this pathway has drawn attention recently for the sustainable productiono fi sobutene, [9][10][11] which is ap recursor of industrial products such as butyl rubbera nd ethyl tert-butyl ether. [12] A variety of inorganic solid catalysts have been tested for C-C hydrolytic bond cleavage reactions includingm ixed metal oxides [9,10,[12][13][14] and acidic zeolites [15][16][17][18][19] with effortsf ocusedo n catalysta ctivitya nd stability.T he fission has thus far only been observed in vapor phase conversion at high temperatures (> 350 8C), and it is not clear whether these productsr esult from the cleavage of aldol addition products or the cleavage of aldol condensation products.M oreover,l ittle is known about optimizing chemoselectivity for either condensation or fission products.…”

Section: Introductionmentioning

confidence: 99%

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Intraparticle Diffusional versus Site Effects on Reaction Pathways in Liquid‐Phase Cross Aldol Reactions

et al. 2018

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Chemo- and regioselectivity in a heterogeneously catalyzed cross aldol reaction were directed by tuning the nature of the sites, textural properties, and reaction conditions. Catalysts included sulfonic acid-functionalized resins or SBA-15 with varying particle size or pore diameter, H-BEA zeolites, and Sn-BEA zeotype; conditions were 25 °C to 170 °C in organic media. Benzaldehyde and 2-butanone yielded branched (reaction at -CH - of butanone) and linear (reaction at -CH ) addition and condensation products; and fission of the branched aldol led to β-methyl styrene and acetic acid. Strong acids promoted the dehydration step, and regioselectivity originated from preferred formation of the branched aldol. Both, resins and functionalized SBA-15 materials yielded predominantly the branched condensation product, unless particle morphology or temperature moved the reaction into the diffusion-limited regime, in which case more fission products were formed, corresponding to Wheeler Type II selectivity. For H-form zeolites, fission of the branched aldol competed with dehydration of the linear aldol, possibly because weaker acidity or steric restrictions prevented dehydration of the branched aldol.

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“…In this reaction, isobutylene was first produced from acetone via the formation of acetone dimer (diacetone alcohol) and trimer (iso-phorone), followed by production of propylene, ethylene and aromatics [21][22][23][24][25][26][27]. These are intermediates in the series of reactions with coke as terminal products.…”

Section: Introductionmentioning

confidence: 99%

Characterization and catalytic performance of modified nano-scale ZSM-5 for the acetone-to-olefins reaction

Konno

Tago

Nakasaka

et al. 2014

Applied Catalysis A: General

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Acidity modification of ZSM-5 zeolite was examined. Phenyl silane and Tri-phenyl silane were newly used as deactivators. Catalytic properties of ZSM-5 zeolites can be controlled. 10 Modified ZSM-5 was effective in acetone-to-olefins reaction.3 AbstractIn acetone to olefins (ATO) reaction using ZSM-5 zeolite, isobutylene is initially produced from decomposition of an acetone dimer, followed by dimerization of isobutylene and its cracking to form ethylene and propylene formation. Nano-scale ZSM-5 zeolite exhibited a stable activity in ATO reaction as compared with macro-scale ZSM-5. In order to improve the 5 catalytic stability of the nano-scale ZSM-5, acidity control in the nano-scale ZSM-5 zeolite by SiO 2 unit formation was examined. Phenyl silane and tri-phenyl silane were newly used as deactivators. This modification allows the increase in the olefins yield as well as improvement of catalyst lifetime. In particular, the regioselective deactivation of acid sites located on the external surface of zeolite inhibits the aromatics formation. Moreover, the acidity control within 10 the pore extremely improves the catalyst lifetime. The acidity-controlled nano-scale ZSM-5 zeolite exhibited stable olefins yield above 55 C-mol% for 180h.

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The Catalyzed Cleavage of Diacetone Alcohol and Other Ketols and Unsaturated Ketones¹

Cited by 32 publications

References 0 publications

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Intraparticle Diffusional versus Site Effects on Reaction Pathways in Liquid‐Phase Cross Aldol Reactions

Characterization and catalytic performance of modified nano-scale ZSM-5 for the acetone-to-olefins reaction

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The Catalyzed Cleavage of Diacetone Alcohol and Other Ketols and Unsaturated Ketones1

Cited by 32 publications

References 0 publications

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Urofuransäuren – eine bisher unbekannte Klasse von Stoffwechselprodukten

Intraparticle Diffusional versus Site Effects on Reaction Pathways in Liquid‐Phase Cross Aldol Reactions

Characterization and catalytic performance of modified nano-scale ZSM-5 for the acetone-to-olefins reaction

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The Catalyzed Cleavage of Diacetone Alcohol and Other Ketols and Unsaturated Ketones¹