Acid hydrolysis of methyl

Data for the acid hydrolysis of methyl acetate (A) at 25°C CH3C02CH3 + H20 = CH3COOH + CH3OH... 

KINETIC DATA FOR THE ACID HYDROLYSIS OF METHYL MES1TOATE AT90oC... 

Entropies of Activation for Acid Hydrolysis of Methyl Aldosidcs... 

The use of Eq. (5) to fit data recorded using a microcalorimeter was first demonstrated by Bakri (6), who studied the acid hydrolysis of methyl acetate in hydrochloric acid. In that experiment, 1 mmol of methyl acetate was added to 2mL of 1 N hydrochloric acid solution in a glass ampoule. The experimental data were fitted to Eq. (5) using a least squares analysis which gave k = 0.116 x 10-3 sec-1 and AH= 1.98 kJmol-1. In this paper, Bakri also shows how the method may be applied to both second-order, solution phase A+B x reactions and to flow calorimetry. 

J. G. Buchanan and J. Conn, The acid hydrolysis of methyl 2,3-anhydro-D-hexopyrano-sides, J. Chem. Soc., (1965) 201-208. 

It is not requisite that the anion eliminated in the step 19 to 20 be a hydroxyl ion, because acid hydrolysis of 5-amino-5-deoxy-l,2-0-isopropylidene - 3 - O - (methylsulfonyl )-a- D -xylofuranose likewise yields 3-pyridinol (21). On subjection to acid hydrolytic conditions which remove the 2V-acetyl group, such N-acetyl derivatives as 5-acetamido-5-deoxy-a-D-xylopyranose (see p. 167) are immediately transformed, through 17, into 3-pyridinol (21). Furthermore, acid hydrolysis of methyl 5-acetamido-5-deoxy-2,3,4-tri-0-methyl-a-D-... 

Since acid hydrolysis of methyl a-D-altroside leads principally to D-altrosan, it became necessary to resort to other devices in order to complete the transformation to the free sugar. The pioneer work of Robertson and his collaborators had established a clear route from D-glucose to many D-altrose derivatives. The final steps, as described by Richtmyer and Hudson, are the acetolysis of methyl o-o-altroside (XXXVIII), or more simply of its benzylidene derivative (XXXVII), followed by catalytic deacetylation of the pentaacetyl-a-D-altrose thus produced. In this way crystalline D-altrose becomes readily available. 

The methanol obtained from the acid hydrolysis of methyl hydrogen succinate in water containing O18 contained none of the heavy isotope 7... 

Derivation (1) By treatment of sodium formate and sodium acid formate with sulfuric acid at low temperatures and distilling in vacuo (2) by acid hydrolysis of methyl formate (3) as a by-product in the manufacture of acetaldehyde and formaldehyde. 

First-order Rate Constants for the Acid Hydrolysis of Methyl a-D-Glucsopyranoside, Recalculated so as to be Valid at Ho = + 0.13... 

Because the Zucker-Hammett hypothesis is invalid and Bunnett s criterion is unreliable, Withey and Whalley studied the effect of pressure on the rate of acid hydrolysis of methyl a-n-glucopyranoside. The value they obtained for the volume of activation clearly shows that the reaction must be unimolecular. 

Rate Constants" for the Acid Hydrolysis of Methyl D-Xylopyranosides and... 

The introduction into a sugar of a halogen atom in place of a hydroxyl group might influence the general reactivity either by steric or electronic effects. Such effects have been extensively discussed with respect to the acid hydrolysis of methyl glycopyranosides, and it is generally considered that, except for substituents at C-2, steric factors predominate. 

The acid hydrolysis of methyl 2,4,6-trimethylbenzoate (33 R = R = CH3) has been studied at various temperatures over the range 3-1 to 11-5m H2SO4 (Bender et al., 1961b). The rate of hydrolysis was... 

Nakano J, Rmby BG (1962) Acid hydrolysis of methyl glucosides and methyl glucuronosides. Svensk Papperstid 65 29-33... 

Ishij T, Ishizu A, Nakano J (1976) Acid hydrolysis of methyl chlOTodeoxyglycosides. Carbohydr Res 48 33-40... 

In aqueous solution, the effectiveness of micellar systems as catalysts is quite often found to increase with the length of the alkyl chain. For example, the rate of acid hydrolysis of methyl o-benzoate in the presence of sodium alkyl sulfates increases in the order Cs < Cio < Cn < Cu < Cie. Such a result may be attributed to either electrostatic or solubilizing effects, or both. It might be expected that any effects due to electrostatic interactions would also increase. Alternatively (or additionally), the increasing aggregation number found in the series may result in a significant increase in the solubilizing power of the system. The importance of each mechanism will depend upon the specifics of the reaction. 

In the case of acid hydrolysis of methyl ethylene phosphate, ring opening occurs with only 30% of the material and 0-C fission occurs in the remainder (5.357). Exclusive 0-C fission with complete retention of the ring occurs in hydrolysis (5.358). 

The initial step of methanol conversion is composed of carbonylation to methyl acetate and dehydration to DME in parallel (see scheme below). DME is successively carbonylated to form methyl acetate. Methyl acetate is further carbonylated to acetic anhydride, which is rapidly hydrolyzed to acetic acid. Hydrolysis of methyl acetate to acetic acid and methanol proceeded also on the carbon support. Thus, carbonylation of methanol proceeds through a set of parallel and series reactions that produce methyl acetate and DME as primary products with acetic acid as the ultimate product, according to following reaction pathways (32,33) ... 

In contrast, lithiocarborane reacts with a variety of halides to give mono-substituted carboranes. Carboranecarboxylic acid is obtained by acid hydrolysis of methyl carborane-l-carboxylate (334), which in turn can be directly prepared from decaborane (Section III, C, 1). In comparison, dimethyl 1,2-carboranedicarboxylate cannot be hydrolyzed to the diacid with acidic reagents and in the presence of aqueous base, hydrolysis occurs only with difficulty and in poor yield, affording the salt of the diacid (XXXVIII) 327). Furthermore, the diester can neither be transesterified nor converted to the diamide via ammonolysis 334). In general, the diacid... 

A kinetic study of acid hydrolysis of methyl a- and -o-glucopyranosides has revealed direct participation by the counterion (Br or Cl ), which becomes more pronounced as the proportion of 1,4-dioxane is increased. ... 

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