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Methane sulfonic acid esters

Kitz, R. and Wilson, I.B. (1962) Esters of methane sulfonic acid as irreversible inhibitors of acetylcholinesterase. Journal of Biological Chemistry, 237, 3245-3249. [Pg.243]

Esterification Reactions. The use of solid acids provides a practical substitute for homogeneous acid catalysts commonly employed to prepare alkyl esters. The use of homogeneous acid catalysts, such as sulfuric acid, and p-toluene- or methane-sulfonic acids, generally results in sulfur contamination of the final product, which upon combustion yield compounds that are known pollutants. [Pg.85]

Another reason that isothermal heating methods are used in the initial screen is to identify materials that have time dependent thermal stability. These materials have a thermal decomposition that does not follow a simple Arrhenius relationship in which the reaction rate increases exponentially with an increase in temperature. Instead an extended induction period is required before the decomposition becomes detectable. An example of this behavior is shown in Figure 2. The DTA isothermal test recorder traces of methane sulfonic acid, 3,7-dimethyloctyl ester at different test temperatures are shown. The induction time varies from less than 1 hr. at 180 C to 46 hr. at 130 C. As with this compound, it is not unusual that once decomposition is detected it proceeds very rapidly, releasing all of the heat in a short period of time. Dynamic heating methods do not indicate if this type of thermal instability is present if it is, the initial detection temperature from dynamic tests will be grossly misleading as to the thermal stability of the material. [Pg.62]

Ethylene imines Esters of methane sulfonic acid... [Pg.105]

In this context our interest was focused on sulfonic acid esters of starch, derived fh)m the reaction of organic sulfonyl chloride (e.g. benzene, methane, or toluene sulfonyl chloride). These derivatives can be employed as partially protected and reactive intermediates. Up to now, especially the reaction of starch with p-toluenesulfonyl chloride in pyridine was studied, i.e. under heterogeneous reaction conditions, which may be accompanied by several side reactions. Alternatively, a homogeneous procedure was published using dimethyl sulfoxide as solvent for starch. However, the sulphur contents of the products were very low and an extensive degradation of the polymer occured . The extent of / toluenesulfonyIation of primary and secondary groups was determined by the iodination method. It was revealed that the reaction proceeds faster at 0-6 than at 0-2 and 0-2... [Pg.206]

This complex also catalyzes the reaction of higher alpha-oleftns and internal olefins to form linear esters. The reaction of octane with 1 atm of CO in methanol with added methane sulfonic acid formed high yields of methyl nonanoate. The same reaction of 2-, 3-, or 4-octene with 4 atm of CO, shown in Equation 17.38i generated the same methyl nonanoate. The selectivity for the linear product ranged from 94% for 4-octene to 99% for 2-octene and 1-octene. The reactions of the branched olefins 2-, 3-, and 4-methyl-l-pentene formed the terminal ester, as did 4-methyl-2-pentene. ... [Pg.779]

An aiyl methane- or toluenesulfonate ester is stable to reduction with lithium aluminum hydride, to the acidic conditions used for nitration of an aromatic ring (HNO3/HOAC), and to the high temperatures (200-250°) of an Ullman reaction. Aiyl sulfonate esters, formed by reaction of a phenol with a sulfonyl chloride in pyridine or aqueous sodium hydroxide, are cleaved by warming in aqueous sodium hydroxide. ... [Pg.168]

In the synthesis of 162, catalytic hydrogenation of lysergic acid proceeds from the less hindered side of the molecule to afford the derivative with the trans ring junction (158). As above, reduction of the methyl ester (159) gives the corresponding carbinol. This is then converted to the methane sulfonate (160), and that function is displaced with cyanide ion to afford the acetonitrile derivative 161. [Pg.479]

On the basis of studies on the metabolism of the fish anesthetic, methane sulfonate of m-aminobenzoic acid ethyl ester (MS-222), by a shark (the spiny dogfish, Squalus aeanthias), Maren et al. (25) reported the formation of a metabolite, m-aminobenzoic acid, by cleavage of the ester bond (Figure 1). This ester-hydrolyzed product was not partitioned across the gill, but was slowly excreted by the kidney. [Pg.125]

CHLOROETHYLMETHANESULFONATE CHLOROETHYL METHANESULPHONATE CHLORO-METHANE SULFONATE d ETHYLE (TRENCH) METHANESULFONIC ACID CHLOROETHYL ESTER NSC-18016... [Pg.330]

SYNS ENT 51,799 METHANESULFONIC ACID, METHYLENE ESTER O METHYLENE BIS(METHANE-SULFONATE)... [Pg.921]

SYNS as-DLMETHYL SULPHATE METHANE-SULPHONTC ACID METHYL ESTER METHYL ESTER of METHANESULFONIC ACID METHYL ESTER of METHANESULPHONIC ACID METHYL METHANE-SULFONATE n METHYL METHANESULPHONATE METHYL METHANSULFONAT (GERMAN) METHYL METHANSULFONATE METHYL METHANSULPHON-ATE MMS NSC-50256... [Pg.933]

Various sulfuric and phosphoric acid esters have sometimes been used instead of alcohols as starting materials for the preparation of nitriles. Of more general importance are sulfonates, particularly from methane- or p-toluene-sulfonic acid, which react in an 5N2-type substitution with cyanide ions. The most common starting materials are, as described in Section 1.8.1.2.1, alkyl halides, and if their preparation creates problems, the use of sulfonates may be advantageous. The addition of crown ethers or the... [Pg.235]


See other pages where Methane sulfonic acid esters is mentioned: [Pg.280]    [Pg.280]    [Pg.103]    [Pg.217]    [Pg.76]    [Pg.103]    [Pg.48]    [Pg.66]    [Pg.580]    [Pg.105]    [Pg.510]    [Pg.212]    [Pg.618]    [Pg.580]    [Pg.174]    [Pg.337]    [Pg.340]    [Pg.299]    [Pg.539]    [Pg.444]    [Pg.227]    [Pg.124]    [Pg.128]    [Pg.329]    [Pg.535]    [Pg.231]    [Pg.122]    [Pg.378]    [Pg.522]    [Pg.206]    [Pg.229]    [Pg.276]   


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Methane acidity

Methane esters

Methane sulfonic acid

Sulfonate esters

Sulfones sulfonic acid esters

Sulfonic acid esters

Sulfonic esters

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