Meyer method

Nitromethane [75-52-5] is produced in China. Presumably a modified Victor Meyer method is being employed. Nitromethane is transported in dmms or smaller containers. Two tank cars of nitromethane exploded in separate incidents in the 1950s. Both explosions occurred in the switching yard of a railroad station. In both cases, essentially adiabatic vapor compression of the nitromethane—air mixture in the gas space of the tank car resulted in the detonation of the Hquid nitromethane. Other nitroparaffins do not, however, detonate in this manner. 

Brenneman and Nair (2001) and McGrath and Lin (2001) showed that the method of Box and Meyer (1986) can be problematic as described below when more than one factor has a dispersion effect. Brenneman and Nair (2001) examined the consequences of using the Box-Meyer method when there is a log-linear dispersion model in which... 

On the dyestuffs example, the Bergman-Hynen method also signals factor F as being related to dispersion. With the main effects of A and F in the location model, F has a Bergman-Hynen statistic of 3.27 (p-value = 0.001). The next strongest effects, as with the Box-Meyer method, are the ADEFinteraction, with a statistic of 2.24 (p-value = 0.017) and the CEF interaction, with a statistic of 0.45 (p-value = 0.035). 

At the beginning of the 20th century Pfeiffer and coworkers " and Pope and Peachey , then Druce and Lambourne improved the Meyer method and synthesized a series of alkylstannone acids and studied their... 

A compound of the empirical formula CHj,0 and with a boiling-point of 19s gives the following data as the result of a determination of the vapor density by the Victor Meyer method. 

Meyers method has been modified to allow it to be operated under phase-transfer conditions.This is a convenient way of converting dibenzyl sulfones directly into ( )-stilbenes (equation S), but it is not so useful for less reactive substrates. 

Since the late 1970s, the Ramberg-Backlund reaction has been used to convert a wide variety of six-membered cyclic a-halo sulfones into cyclopentenes, often in high yield and useful regioselective syntheses of both 2- and 3-cyclopentenones, using sequences in which the Ramberg-Backlund reaction is the key step, have also been reported. Bu OK in THF, diethyl ether or DME are the preferred conditions for these reactions and, in addition, Meyers method has been used to convert six-membered cyclic sulfones directly into cyclopentenes. Examples of these reactions follow. 

Constitution. Chatterjee (269) compared the near-ultraviolet absorption spectra of umbellatine and berberine and observed curves of marked similarity. The base contains a methylenedioxy group, two methoxyls and bwo hydroxyls. An AT-methyl group can be detected by the Herzig-Meyer method. 

Nicolaou and co-workers revisited these general conditions during their landmark total synthesis of thiostrepton. Notable features in ring construction during this synthesis include higher reaction temperatures than those used in the Meyers method and the isolation of the crude hydroxythiazoline before the elimination step, which was then conducted employing TFAA in the presence of pyridine followed by triethylamine. These reaction conditions also led to A -trifluoroacetylation of the free —NH... 

The alkyl iodide can be determined by gravimetry, iodometry, or gas chromatography, and identified by the latter method or by preparing derivatives recommended for alkyl halides Alkoxy groups undergo dealkylation more readily than amines, and in the presence of the former, after addition of the hydriodic acid the sample should be subjected first to distillation at 150°, in order to determine the alkoxy groups, and then to pyrolysis at 360°, where the Herzig-Meyer method is operative The method is further discussed elsewhere... 

The Meyers method is one of the very few asymmetric syntheses which allow the rational generation of axial chirality, as for example, in the chiral binaphthyl (88).t l We will see an application of this axial asymmetric induction in section 7.2.4. 

Problem 19.—Write equations to illustrate the reactions involved in the Victor Meyer method for the differentiation between I, II and III alcohols. Weyl, p 753 (1911). 

It is interesting that, whereas esterification of duroic acid is not effected by the Victor Meyer method, its vinylog, the enol, underwent etherification under these conditions. Heating with methanol in the presence of hydrogen chloride sufficed to convert it into the methyl ether, which in turn is a vinylog of an ester. The enol ether was saponified by aqueous sodium hydroxide, the salt of the enol being formed. 

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