Containers methyl bromide

Formulation Types Fiunigant (mixture containing methyl bromide, methyl isothiocyanate, 1,2-dichloropropane and 1,3-dichloro-l-propene). 

Cylinders containing methyl bromide should not be subjected to rough handling... 

Organic compounds normally cause Htde or no corrosion of magnesium. Tanks or other containers of magnesium alloys are used for phenol [108-95-2] methyl bromide [74-96 ] and phenylethyl alcohol [60-12-8]. Most alcohols cause no more than mild attack, but anhydrous methanol attacks magnesium vigorously with the formation of magnesium methoxide [109-88-6]. This attack is inhibited by the addition of 1% ammonium sulfide [12135-76-1] or the presence ofwater. 

Although ethereal solutions of methyl lithium may be prepared by the reaction of lithium wire with either methyl iodide or methyl bromide in ether solution, the molar equivalent of lithium iodide or lithium bromide formed in these reactions remains in solution and forms, in part, a complex with the methyllithium. Certain of the ethereal solutions of methyl 1ithium currently marketed by several suppliers including Alfa Products, Morton/Thiokol, Inc., Aldrich Chemical Company, and Lithium Corporation of America, Inc., have been prepared from methyl bromide and contain a full molar equivalent of lithium bromide. In several applications such as the use of methyllithium to prepare lithium dimethyl cuprate or the use of methyllithium in 1,2-dimethyoxyethane to prepare lithium enolates from enol acetates or triraethyl silyl enol ethers, the presence of this lithium salt interferes with the titration and use of methyllithium. There is also evidence which indicates that the stereochemistry observed during addition of methyllithium to carbonyl compounds may be influenced significantly by the presence of a lithium salt in the reaction solution. For these reasons it is often desirable to have ethereal solutions... 

Preparation of the Methyl Bromide To the acetone solution of the free base was added an acetone solution, containing an excess of methyl bromide. Within a few minutes the methobromide started to crystallize. The mixture was allowed to stand for several hours. The crystallized solid was filtered, and additional product was obtained by evaporation of the filtrate. The yield was nearly quantitative. After recrystallization from acetone, the product melted at 329°C. 

A mixture containing 8 g (0.06 mol) of N-methyl-3-chloro-piperidine and 13.6 g (0.06 mol) of benzilic acid in 50 cc of anhydrous isopropyl alcohol was refluxed for 3 days the isopropyl alcohol was removed by distillation in vacuo, the residue treated with dilute aqueous hydrochloric acid and the aqueous acid mixture extracted repeatedly with ether. The aqueous phase was separated, made strongly alkaline with 20% aqueous sodium hydroxide and extracted with ether. The ether extracts were dried with potassium carbonate and distilled the product was collected at 175° to 176°C (0.03 mm), yield 11.5 g (59%). The ester base thus prepared was then dissolved in 75 cc of isopropyl alcohol and 3.4 g (0.037 mol) methyl bromide added. The reaction mixture was allowed to stand at 30°C for 2 days and the product isolated by filtration, yield, 13 g (87%), MP 228° to 229°C dec. 

In a one-liter separatory funnel, 94 g (0.215 mol) of scopolamine hydrobromide trihydrate was dissolved in 250 ml of water, made alkaline by shaking with 40 g (1 mol) of sodium hydroxide in 150 ml of water, and the free base immediately extracted with ether. As scopolamine is somewhat soluble in water, the aqueous layer was saturated with potassium carbonate and again extracted with ether. The combined ether extracts were dried over anhydrous magnesium sulfate and the ether removed by distillation, leaving 65 g (0.214 mol 100% yield) of nearly colorless oil. Then 100 g (1.05 mols) of cold methyl bromide was added to a chilled, 500-ml pressure flask containing the 65 g of scopolamine, the flask stoppered tightly with a clamp, and allowed to stand at room temperature for 96 hours. 

Isobutylene, methyl chloride, methyl bromide, ethyl chloride (Linde Div. Union Carbide Corp.) were obtained in high purity and were further purified by passing through a column containing barium oxide and molecular sieves. 

Isobutylene (Philips Research Grade) was purified as described [17] by distillation on a vacuum line through a trap containing sodium at 350 °C. It was stored as liquid on a sodium mirror. Solutions in methyl bromide were made up by distilling the required quantities of solvent and isobutylene from hanging burettes along a vacuum line into a reservoir with Teflon tap, which was subsequently cut from the vacuum line and fused to a burette with Teflon tap which was then fused to the main vacuum manifold as shown in Figure 1. 

Alkylation of 2,4-disubstituted-5(477)-oxazolones can be conveniently performed via phase-transfer catalysis. For example, the substrate and an alkyl halide are dissolved in an organic solvent and stirred with an aqueous sodium carbonate solution containing tetrabutylammonium bromide as a phase-transfer catalyst. 4,4-(Diarylmethyl)-2-phenyl-5(4/f)-oxazolones can be prepared in one-step by dialkylation of 146 using magnesium methyl carbonate and the corresponding... 

The water collected during the reaction contains practically no hydrobromic acid but is saturated with guaiacol and methyl bromide. Nevertheless, it scarcely pays to recover the dissolved compounds, for on distillation only 1-2 g. of wet guaiacol can be collected while the value of the methyl bromide is in any case not very great. 

Consider the hydrolyses of methyl bromide (Reaction 1 in Table 13.2) and ethyl acetate (reaction 5 in Table 13.2) at 25°C and pH 7.0 in a contaminated groundwater containing 100 mM Cl and 1 mM Br. Assume that neither the pH nor the inorganic species concentrations change significantly during the reaction. Also assume that the activity coefficients of all species are 1. To what extent do the two compounds hydrolyze under these conditions ... 

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