74-83-9 Bromomethane

Scientific and common names, and synonyms BROMOMETHANE, MONOBROMOMETHANE METHYL BROMIDE METHANE. BROMO-  

Country Effective Date Description of action taken Grounds for decision 

NLD 1992 The chemical is severely restricted, in 1981, the use of methyl bromide as a soil disinfectant was prohibited. Based on Article 16a ofthe Dutch Pesticide Law of 1962, an exemption could, however, be granted based on individual requests. In the following period of time, the policies of the Government aimed at a further decrease in the use of methyl bromide. In 1992 methyl bromide was completely banned for use as a soil disinfectant. In 1996, two space fumigation products on the basis of methyl bromide were extended until 1 December 2001. (Reference (EP3) UNEP/FAO - PIC Circulars XIV, XV, XVI, XVII - 12/2001,6/2002, 12/2002,6/2003, ) 

FAO PLANT PRODUCTION PROTECTION PAPER, 72/1, 1985 FAO PLANT PRODUCTION PROTECTION PAPER, 72/2, 1985 IPCS HEALTH AND SAFETY GUIDE, 86, 1994 

Halide Oceans (73, 74) Sedimentary rocks (66, 74) Fungi (75) Wood pulp (218) Plants (74, 76) 

In previous years some 20,000 metric tons of CH3Br was used annually in the US as a soil pesticide (331). 

Despite the low abundance of bromide relative to chloride in sediments, soil, and the ocean (Table 3.4), the ease with which nature can manipulate bromide (reduction potentials E° - 1.09 V for Br vs. 1.36 V for Cl. 0.54 V for I-, and 2.87 V for F (2671)) results in a multitude of natural organobromine compounds especially in the oceans (41, 45) (Table 3.5). 

The abiotic bromination involving the alkylation of bromide during Fe(III) oxidation of natural organic phenols in organic matter is a pathway to CH3Br that has been demonstrated in the laboratory (175). 

Where there is halide, carbon, oxygen, and fire there will be organohalogens. Such is the case with bromide giving rise to CH3Br in forest fires (223, 284, 285, 288). Indeed, vegetation fires are a major source of CH3Br (285). 

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Bromine is used in the manufacture of many important organic compounds including 1,2-dibromoethane (ethylene dibromide), added to petrol to prevent lead deposition which occurs by decomposition of the anti-knock —lead tetraethyl bromomethane (methyl bromide), a fumigating agent, and several compounds used to reduce flammability of polyester plastics and epoxide resins. Silver(I) bromide is used extensively in the photographic industry... 

The reaction itself works by the action of Na or K from NaOH or KOH which form what is called a catechoxide dianion with the two OHs of the catechol species. This makes the two ripe for an attack by a methylene halide which can be either DCM (methylene chloride, or dichloromethane), DBM (methylene bromide, or di-bromomethane) or DIM (methylene iodide, or diiodomethane). DCM is cheap and works pretty well, but DBM and DIM work better yet are more expensive. 

The carbon atom m bromomethane can accept an electron pair if its covalent bond with bromine breaks with both electrons m that bond becoming an unshared pair of bromide ion Thus bromomethane acts as a Lewis acid m this reaction... 

Dimethylsulfoxide Acyl and aryl halides, boron compounds, bromomethane, nitrogen dioxide, magnesium perchlorate, periodic acid, silver difluoride, sodium hydride, sulfur trioxide... 

Other Bromomethanes. Bromochloromethane [74-97-5] (methylene chlorobromide), CH2BrCl, is a clear, colorless Hquid with a characteristic sweet odor and very low freezing point, —88.0°C. Its properties include bp, 68.1°C 1.9229 g/mL 1.4808 heat of vaporization at bp, 232 J /g... 

CH3BR BROMOMETHANE -55.241 8.0199E-02 1.1207E-05 -28.16 69 C2H402 METHYL-FORMATE -350.914 1.7474E-01 1.6322E-05 -297.19... 

Chemical Designations - Synonyms Bromomethane Embafiime M-B-C Fumigant ... 

Rate constants have been measured for the reactions of boron compounds with a series of bromomethanes and bromofluoromethanes. Previously it was shown that the reactivity of the chlorine in chlorofluoromethane is substantially reduced by increasing fluorine substitution. The corresponding decrease in the reactivity of bromolluoromethane u as not observed [ifS]. 

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