Acetal Formation for Ketones and Aromatic Aldehydes with Methanol<sup>1</sup>

Bell, James M.; Kubler, D. G.; Sartwell, P.; Zepp, Richard G.

doi:10.1021/jo01023a067

Cited by 49 publications

(28 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the case of Pt/SiO 2 and Pt/CeO 2 there was some evidence for competition between furfural hydrogenation to furfuryl alcohol versus acetalization, with their respective selectivities exhibiting a weak anti-correlation. It is interesting to note that the acetalization side reaction, generally considered to be acid catalyzed, was suppressed over the most basic Pt/MgO and Pt/ZnO catalysts [34,35]. As a result of the acetalization observed during reaction in ethanol, a range of alternative solvents were investigated to determine whether acetalization could be suppressed while maintaining high rates for the primary hydrogenation of furfural to furfuryl alcohol.…”

Section: Catalytic Reaction Testingmentioning

confidence: 99%

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Taylor

Durndell

Isaacs

et al. 2016

Applied Catalysis B: Environmental

328

205

View full text Add to dashboard Cite

a b s t r a c tThe selective liquid phase hydrogenation of furfural to furfuryl alcohol over Pt nanoparticles supported on SiO 2 , ZnO, ␥-Al 2 O 3 , CeO 2 is reported under extremely mild conditions. Ambient hydrogen pressure, and temperatures as low as 50 • C are shown sufficient to drive furfural hydrogenation with high conversion and >99% selectivity to furfuryl alcohol. Strong support and solvent dependencies are observed, with methanol and n-butanol proving excellent solvents for promoting high furfuryl alcohol yields over uniformly dispersed 4 nm Pt nanoparticles over MgO, CeO 2 and ␥-Al 2 O 3 . In contrast, non-polar solvents conferred poor furfural conversion, while ethanol favored acetal by-product formation. Furfural selective hydrogenation can be tuned through controlling the oxide support, reaction solvent and temperature.

show abstract

Section: Catalytic Reaction Testingmentioning

confidence: 99%

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Taylor

Durndell

Isaacs

et al. 2016

Applied Catalysis B: Environmental

328

205

View full text Add to dashboard Cite

show abstract

“…For benzaldehyde and acetophenone, the equilibrium constants for dimethyl acetal formation have been reported (40,41); then by the methods just described it is straightforward to calculate the equilibrium constants for hydration. For benzaldehyde an independent check is available.…”

Section: Calculation Of Equilibrium Constants For Hydrationmentioning

confidence: 99%

Equilibrium constants for a series of simple aldol condensations, and linear free energy relations with other carbonyl addition reactions

Guthrie¹

1978

Can. J. Chem.

102

View full text Add to dashboard Cite

Can. J. Chem. 56,962 (1978). A set of equilibrium constants for aldol condensations of acetaldehyde, acetone, acetophenone, and acetic acid as nucleophiles and formaldehyde, acetaldehyde, benzaldehyde, acetone, and acetophenone as carbonyl acceptors has been evaluated. The four values determined, directly or indirectly, by experiment have been augmented by values calculated from thermochemical data and equilibriunl constants for enone hydration, and by estimation of free energies of formation of the reaction products by use of hypothetical disproportionation reactions. When the carbonyl nucleophiles are compared to other nucleophiles which can add to carbonyl compounds, it is found that they can be incorporated in the linear free energy relationship of Sander and Jencks, with y values of 0.45 for acetaldehyde, 0.16 for acetone, 0.05 for acetophenone, and 3.56 for acetic acid. These results make it possible t o predict the equilibrium constants for any of a large number of aldol condensations from the equilibrium constant for the addition of any nucleophile to the carbonyl acceptor compound.J. PETER GUTHRIE. Can. J. Chem. 56,962 (1978). On a CvaluC Line strie de constantes d'tquilibre pour les condensations aldoliques de I'acitaldihyde, de I'acttone, de I'acCtophtnone et de I'acide acttique agissant comrne nucleophile alors que la formaldthyde, I'acetaldthyde, la benzaldthyde, I'acttone et l'acttophtnone agissent comme accepteur de carbonyle. Aux quatre valeurs determinees directement ou indirectement a l'aide des exptriences on a pu apporter un complement grice aux valeurs calcultes a partir de donntes thermodynamiques et de constantes d'tquilibre pour I'hydrqation d'enones et aussi gr2ce a des evaluations des Cnergies libres de formation des produits de reaction faites en se basant sur des rtactions de dismutations hypothetiques. Lorsque I'on compare les carbonyles nucltophiles avec d'autres nucltophiles qui peuvent s'additionner sur les groupements carbonyles, on trouve qu'ils peuvent &tre incorports dans la relation lintaire d'tnergies libres de Sander et Jencks avec des valeurs y de 0.45 pour I'acttaldthyde, 0.16 pour I'acttone, 0.05 pour l'acttophtnone et 3.56 pour l'acide acttique. En se basant sur ces rtsultats, il est donc possible de prtdire les constantes d'tquilibre d'un grand nombre de condensations aldoliqi~es en se basant sur la constante d'tquilibre pour I'addition de n'importe quel nucltophile sur un compost carbonylt accepteur.[Traduit par le journal] Introduction The aldol reaction is of enormous importance in synthetic organic chemistry, as witness the entire volume of 'Organic Reactions' required to review it (1). Despite this importance and utility, there have been relatively few mechanistic investigations (2-13) and even fewer studies of the equilibrium constants (4, 6, 14) for simple aldol reactions. In part this is the result of the notorious tendency of aldol reactions to yield complex reaction mixtures, with competing reactions, polymerizations and worse confusing the situation. Noneth...

show abstract

“…The three related equilibria 1-3 involved in hydrate (1)(2)(3)(4)(5)(6), hemiacetal (1)(2)(3)(4)(5)(6)(7), and acetal (6)(7)(8)(9)(10)(11)(12) formation from carbonyl compounds have been I investigated in numerous laboratories. It has been found quite commonly that for a related series of compounds equilibrium constants for any one of these reactions can be correlated using the appropriate o parameters (2,3,6,12).…”

Section: Introductionmentioning

confidence: 99%

“…It has been found quite commonly that for a related series of compounds equilibrium constants for any one of these reactions can be correlated using the appropriate o parameters (2,3,6,12). Sander and Jencks (13) have shown that the equilibrium constants for hemiacetal and hydrate formation are often in constant proportion, depending only on the relative tendencies to add to carbonyl groups of the alcohol and water molecules.…”

Section: Introductionmentioning

confidence: 99%

Carbonyl Addition Reactions: Factors Affecting the Hydrate–Hemiacetal and Hemiacetal–Acetal Equilibrium Constants

Guthrie¹

1975

Can. J. Chem.

178

142

View full text Add to dashboard Cite

Equilibrium constants for hydrate–hemiacetal interconversion in aqueous solution at 25° have been measured for four fluorinated carbonyl compounds: compound, alcohol, K4 (M−1): CF3CHO, C2H5OH, 2.3; CF3COCH3, CH3OH, 1.0; CF3COPh, CH3OH, 3.5; CF3COCF3, CH3OH, 0.14. These values, combined with values from the literature, permit an examination of substituent effects upon the equilibrium constant for[Formula: see text]The free energy change for this process, corrected for symmetry and steric effects, follows the equation[Formula: see text]Thus electronic effects upon this equilibrium are generally small and in fact are often smaller than steric effects.This analysis permits and justifies the calculation of free energies of formation of [Formula: see text] compounds from the (more generally measurable) free energies of formation of the analogous [Formula: see text] compounds.

show abstract

Acetal Formation for Ketones and Aromatic Aldehydes with Methanol¹

Cited by 49 publications

References 3 publications

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Equilibrium constants for a series of simple aldol condensations, and linear free energy relations with other carbonyl addition reactions

Carbonyl Addition Reactions: Factors Affecting the Hydrate–Hemiacetal and Hemiacetal–Acetal Equilibrium Constants

Contact Info

Product

Resources

About

Acetal Formation for Ketones and Aromatic Aldehydes with Methanol1

Cited by 49 publications

References 3 publications

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Highly selective hydrogenation of furfural over supported Pt nanoparticles under mild conditions

Equilibrium constants for a series of simple aldol condensations, and linear free energy relations with other carbonyl addition reactions

Carbonyl Addition Reactions: Factors Affecting the Hydrate–Hemiacetal and Hemiacetal–Acetal Equilibrium Constants

Contact Info

Product

Resources

About

Acetal Formation for Ketones and Aromatic Aldehydes with Methanol¹