Dibromomethane
issed by the supplier of BST Tianjin Co., Ltd.
Maybe there are some people who want to ask how to use dibromomethane or what usages are for dibromomethane ?
Let me explain you in details below
The fist usage of the main ones is as follows:
Dibromomethane can be used for the monobromination reaction of enol anions. Due to the high steric hindrance typically generated by enol anions, there is no double substitution reaction with dibromomethane. Typical examples include the bromination methylation reaction of cyclobutane carboxylate (Equation A ) [4] and tetrahydronaphthalenone carboxylate (Equation A)
The second usage as follows,
Dibromomethane can be used to replace diiodomethane in the cyclopropanization reaction of olefins (equations B) . This reaction requires the participation of metal Zn, and the activity of Zn greatly affects the yield of the reaction. Usually, copper chloride or acetyl chloride is added to activate metal Zn, thereby forming the intermediate (bromomethyl) zinc bromide to achieve cyclopropanization reaction.
The third usage as follows，
Dibromomethane can be used organic synthesis raw materials. Can be used as a component for solvents, refrigerants, flame retardants, and antiknock agents; Used as a disinfectant and analgesic in the pharmaceutical industry. It is also used for pesticide nitrile and other organic synthesis.
The next usage as follows,
Dibromomethane is an effective reagent for the formation of methylene carboxylaldehyde, so the reactions it participates in are usually irreversible. Not only can cis carboxylaldehyde be formed, but it can also react with sugar compounds to form stable trans carboxylaldehyde (equations C). Due to the presence of hydroxyl groups in the reaction substrate, the reaction can be carried out in polar solvents such as water, but requires the participation of phase transfer reagents such as tetrabutylammonium bromide.
The next usage as follows,
The mixed reagent composed of dibromomethane, Zn, and TiCl4 can efficiently convert carbonyl C=O to C=CH2 under mild conditions, making it an effective methylation reagent for carbonyl compounds. The biggest advantage of this mixed reagent compared to traditional Wittig reagents is that it does not cause enolation reactions of ketones, making it very versatile, such as the synthesis of natural products (Formula D1) and the conversion of ordinary chiral reagents (Formula D2).
The next usage as follows,
Used another similar reactions can also be achieved using other phase transfer catalysts such as alkyl trimethylammonium to achieve the methylene carboxylation reaction of catechol (equation E) and the monosulfide carboxylation reaction of mercaptophenol (equation E).
The next usage as follows,
Dibromomethane is a raw material for the preparation of fungicides nitrile and imidazole.
continue…………………..
If you have other usage except above,kindly contact BST TIANJIN CO., Ltd,we can discuss further,please.
Besides, let us discuss the synthesis of line in the lab or industry only for your reference below,
1. The tribromomethane method first reacts with arsenic trioxide and liquid alkali to prepare a sodium arsenite solution. The sodium arsenite solution is heated to 65 ℃, and bromoform is slowly added under stirring. After all is added, stirring and reflux are continued for 4 hours to complete the reaction. The reactant is poured into 5-6 times water, and the oily substance is sucked out for fractionation. Wash with water until neutral, dehydrate with calcium chloride, distill, and obtain the product from Chemicalbook. Raw material consumption quota: 8300kg/t of bromoform, 1200kg/t of arsenic trioxide, and 16500kg/t of 40% liquid alkali.
2. The dichloromethane method is still used in industry to produce anhydrous CH2Cl2 by reacting with HBr under the catalysis of anhydrous AlBr3, while also producing chlorobromomethane.
3. Bromochloromethane hydrogen bromide method.
Also let us know the basic informtion of the chemcial
Common Name Dibromomethane
CAS Number 74-95-3
Molecular Weight 173.835
Density 2.4±0.1 g/cm3
Boiling Point 97.0±0.0 °C at 760 mmHg
Molecular Formula CH2Br2
Melting Point -52 °C
MSDS Document
Flash Point -22.1±17.7 °C
Do you want to know what specificaiton fo Dibromomethane?
Specification:
Appearacnce: colorless clear liquid
Purity:99% min by GC
IR and HNMR conform:ok
Appearance:
HNMR picture is as follows,
IR picture is as follows,
GC picture is as follows,
Through special testing equipment and above methods, to identify the quality of Dibromomethane
Synnyoms as follows,
EINECS 200-824-2
Methylenbromid
DBM
dibromo-methane
Methylene Bromide
METHYLENE DIBROMIDE
Methane,dibromo
Methane, dibromo-
dibromomethylene
Links of Articals cited as follows,
(1) how to use the chemial in the matter of dangerous……
(2) Podsiadlo M.; Dziubek K.; Szafranski M.; Katrusiak A. (December 2006). "Molecular interactions in crystalline dibromomethane and diiodomethane, and the stabilities of their high-pressure and low-temperature phases". Acta Crystallogr. B. 62 (6): 1090–1098(9). doi:10.1107/S0108768106034963. PMID 17108664. Retrieved 2007-06-29.
- ^ "methylene bromide - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 25 March 2005. Identification. Retrieved 18 June 2012.
- ^ Jump up to:a b Dagani, M. J.; Barda, H. J.; Benya, T. J.; Sanders, D. C. "Bromine Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_405.
- ^ W. W. Hartman, E. E. Dreger (1929). "Methylene bromide". Org. Synth. 9: 56. doi:10.15227/orgsyn.009.0056.
