Evidence for a solvent-induced change in rate-limiting step in the hydrolysis of benzaldehyde dimethyl acetal

Young, Paul R.; Bogseth, Roy; Rietz, Edward

doi:10.1021/ja00540a015

Cited by 13 publications

(10 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values of k H and the ρ coefficient are similar to those obtained by Fife, 16 Cordes, 5 Jensen 17 and Young 10 in aqueous and water-organic solvent mixtures. (9a) (9b) (10) resides in the Stern region; the fact that catalysis occurs rather than inhibition indicates that the substrate is not wholly immersed in the hydrophobic core of the micelle (although its aromatic component resides in this region).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Reactions within association complexes: acid catalysed hydrolysis of substituted benzaldehyde acetals in the presence of detergents

Rose

Williams

2002

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

First order rate constants for decomposition of substituted benzaldehyde dimethyl acetals at constant pH in solutions of sodium dodecyl sulfate (SDS) and Aerosol AOT (AOT) maintained at constant [Na ϩ ] are linear in surfactant concentration. When the only Na ϩ is that derived from the added SDS the kinetics exhibit a saturating rate law in SDS concentration. The present study shows that the curvature is not due to complexation of substrate but to ion exchange whereby increasing [Na ϩ ] expels H ϩ from the Stern region where reaction of the substrate occurs. Increasing [Na ϩ ] at constant [SDS] inhibits the SDS-catalysed acid hydrolysis of 4-isopropylbenzaldehyde dimethyl acetal and the dissociation constant of the Na ϩ -SDS micelle complex is 0.0281 M which agrees with values calculated from previous data using different reactions. The complex to SDS of a neutral analogue of the acetals exhibits a dissociation constant (K i ) which is not significantly dependent on the overall concentration of Na ϩ ions in the range 0.07 to 0.42 M. Increasing concentrations of cetyltrimethylammonium bromide (CTAB; cetyl = hexadecyl) inhibit the acid catalysed hydrolysis; equilibrium constants (K i ) for the dissociation of the CTAB-complexed acetals fit a Hansch plot and possess no contribution from Hammett's sigma.

show abstract

Section: Resultsmentioning

confidence: 99%

“…19 Hydrolysis may be accelerated by complexing the acetal in the Stern region of a micelle bearing anionic groups possibly by stabilisation of the protonated acetal (Scheme 1 and eqn. (10)). The substrate will be located so that only the acetal function Scheme 1 (8)…”

Section: Discussionmentioning

confidence: 99%

Reactions within association complexes: acid catalysed hydrolysis of substituted benzaldehyde acetals in the presence of detergents

Rose

Williams

2002

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

show abstract

“…Benzyltrimethylsilane ( 4) is a hydrogen-abstraction product of (trimethylsilyl)phenylcarbene and is a typical minor product of carbene reactions. The silaindan (6) arises from [o-(trimethylsilyl)phenyl] carbene via a carbene-carbene rearrangement of the (trimethylsilyl)phenylcarbene. 8,9,22 The styrene 5 is probably formed by the thermal decomposition of l,l-dimethyl-2-phenylsilirane (8) produced by the intramolecular C-H insertion of the (trimethylsilyl)phenylcarbene.…”

Section: Resultsmentioning

confidence: 99%

“…Pyrolyses of (trimethylsilyl) [p-(trimethylsilyl)phenyl]methanol ( 24) and (trimethylsilyl) (p-terf-butylphenyl)methanol (25) gave 1,1-dimethyl-l-silaindan (6) and 1,1dimethylindan (26) in 44 and 22% yields, respectively. These products arise from intramolecular insertion of o-(trimethylsilyl)-and (o-tert-butylphenyl)carbenes into the C-H bonds of the o-trimethylsilyl and terf-butyl groups via carbene-carbene rearrangement of p-(trimethylsilyl)and (p-ferf-butylphenyl)carbenes28'29 (Scheme II).…”

Section: Resultsmentioning

confidence: 99%

Pyrolysis of 1-(trimethylsilyl)-1-alkanols. New carbene precursors of silylcarbene and phenylcarbene

Sekiguchi¹,

Andō²

1980

J. Org. Chem.

View full text Add to dashboard Cite

room temperature under reduced pressure. The unreacted dimethyl fumarate was removed by filtration and the residue placed under vacuum for 12 h to remove the unreacted enamine, leaving 0.46 g of 3b as yellow oil. Attempts to further purify 3b resulted in isomerization to 3a: NMR (CDC13) 0.92 (s, 3 ), 1.30 (s, 3 H), 2.7-3.2 (m, 8 H), 3.58 (s, 6 H); IR (thin film) 1737 cm"1 11.Acknowledgment. Support of this work by the National Science Foundation (CHE 78-01120) is gratefully acknowledged.

show abstract

“…Though easily stated, the mechanism for the formation of a charged intermediate [ 5 , 7 – 11 ] followed by attack of water, cleavage of RO–C bonds, and several proton-transfer reactions is non-trivial [ 6 , 8 , 10 , 12 – 13 ]; and indeed the debate about the factors influencing the overall rate of reaction and the synchronicity of steps has yet to achieve consensus [ 11 , 14 – 15 ]. Factors such as solvent [ 13 ], catalyst p K a [ 9 ], –OR basicity [ 6 , 16 – 17 ], the kinetic anomeric effect [ 18 ], the impact of substituents upon the formation [ 10 – 11 19 – 22 ] and reactivity of charged intermediates [ 14 ] have all attracted scrutiny. A generic 2-alkoxy-2-alkyl-1,3-dioxolane A is used to illustrate the generally accepted specific acid-catalysed three-stage hydrolysis mechanism of orthoesters ( Scheme 1 ) [ 23 ].…”

Section: Introductionmentioning

confidence: 99%

The hydrolysis of geminal ethers: a kinetic appraisal of orthoesters and ketals

Repetto¹,

Costello²,

Lam³

et al. 2016

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

SummaryA novel approach to protecting jet fuel against the effects of water contamination is predicated upon the coupling of the rapid hydrolysis reactions of lipophilic cyclic geminal ethers, with the concomitant production of a hydrophilic acyclic hydroxyester with de-icing properties (Fuel Dehydrating Icing Inhibitors - FDII). To this end, a kinetic appraisal of the hydrolysis reactions of representative geminal ethers was undertaken using a convenient surrogate for the fuel–water interface (D2O/CD3CN 1:4). We present here a library of acyclic and five/six-membered cyclic geminal ethers arranged according to their hydroxonium catalytic coefficients for hydrolysis, providing for the first time a framework for the development of FDII. A combination of 1H NMR, labelling and computational studies was used to assess the effects that may govern the observed relative rates of hydrolyses.

show abstract

Evidence for a solvent-induced change in rate-limiting step in the hydrolysis of benzaldehyde dimethyl acetal

Cited by 13 publications

References 4 publications

Reactions within association complexes: acid catalysed hydrolysis of substituted benzaldehyde acetals in the presence of detergents

Reactions within association complexes: acid catalysed hydrolysis of substituted benzaldehyde acetals in the presence of detergents

Pyrolysis of 1-(trimethylsilyl)-1-alkanols. New carbene precursors of silylcarbene and phenylcarbene

The hydrolysis of geminal ethers: a kinetic appraisal of orthoesters and ketals

Contact Info

Product

Resources

About