77-48-5 Usage
Industrial brominating agent and disinfectant
1, 3-Dibromo-5, 5-dimethylhydantoin is primarily used as an industrial brominating agent and antiseptic disinfectant. It is a very useful kind of brominating agent. Compared with brominating agent such as N-bromoacetamide, N-bromosuccinimide, etc. it has a lot of advantages including high content of active bromine, excellent storage stability, and economic application. Therefore, it is widely applied to chemical and pharmaceutical industry such as being used for the bromination of allyl and benzyl compounds as well as aromatic ring, the addition reaction of the bromine in double bond and hydrogen bromide as well as the selective oxidation of secondary alcohols; in addition, it is also a kind of efficient and safe disinfectant with a strong efficacy in killing fungi, bacteria and viruses as well as in killing the adverse algae in the water. It can be applied to the prevention and treatment of many kinds of diseases in aquaculture related to fish, shrimp, frogs and turtles as well as the disinfection of swimming pool, fruit preservation and algae killing via industrial recycled water algae and daily disinfection. For example, the experts in the Beijing SARS prevention and control working panel had proposed for using the 1, 3-Dibromo-5, 5-dimethylhydantoin solution with effective bromine being 500~1000mg/L for spray, mopping and cleaning, having the disinfection for 10~15min to prevent SARS.
Physical and Chemical Properties
1, 3-Dibromo-5, 5-dimethylhydantoin has the English abbreviation be DBDMH with pure product being white solid and the mp being 196~198 ℃. The industrial products appear as a pale yellow solid with a mp of 194~197 ℃; it is soluble in chloroform, ethanol, acetone and other organic solvents, slightly soluble in water with 1 L water being able to dissolve 2.2 g of DBDMH at 20℃ with the pH of 0.1% aqueous solution being 2.6; It is prone to be subject to decomposition in strong acid or alkali; it is stable when dry and is easy to absorb moisture with partially hydrolysis after moisture absorption; it has a slight pungent odor with the active bromine content being 54% to 55%.
Sterilization Mechanism
DBDMH, upon hydrolysis in water, can mainly form hypobromous acid and can release bromine in the form of hypobromous acid. DBDMH, due to able to release bromine in a high reaction rate, can continuously release Br-ions in the water, further playing a bactericidal effect. However, other kinds of halogenated hydantoin, such as 1, 3-Dibromo-5, 5-dimethylhydantoin or bromochlorohydantoin, release the chlorine in a very slow rate, leading to that the time for reaching the peak of sterilization in the water is lagging behind, therefore, DBDMH usually has a higher efficiency than other kind of halogenated hydantoin at relatively rapid bactericidal conditions.
Synthesis of 1,3-Dibromo-5,5-dimethylhydantoin
Adding an appropriate amount of water to dimethyl hydantoin, control the temperature at about 30 ℃ for stirring of 30min until all the dimethyl hydantoin is dissolved. Add drop wise of appropriate amount of bromine within a certain period of time and then have reaction for several hours. After the completion of the reaction, cool the solution, crystallize using ethanol, filter, and dry with the light-yellow solid being finished product of DBDMH.
The optimal condition for experimentally determination and synthesis of DBDMH is: the optimum molar ratio of DMH to bromine is 1: 2.0; the solvent amount is 80 mL (water) /0.1mol (Hein); the reaction temperature should be about 30 ℃; Reaction time is around 5min with the yield of 1,3-dibromo-5,5-dimethylhydantoin being up to 80%.
Uses
Different sources of media describe the Uses of 77-48-5 differently. You can refer to the following data:
1. DBDMH is an important chemical product and has been widely applied in chemical, pharmaceutical and agricultural industries with various kinds of advantages including excellent stability, high content of bromine and high reactive activity. Currently, the combined formulation between DBDMH and other halogenated hydantoin for application has become a hotspot in recent years such as the combined application of BCDMH and DBDMH as well as the combined application of DCDMH and DBDMH. For the combined formulation of DBDMH and other halogenated hydantoin, one critical factor is the ratio between effective chlorine and effective bromine. For example, at pH 7.1, compound formulation with the same dose of BCDMH and DBDMH has a significantly higher bactericidal efficacy than DBDMH alone or BCDMH alone. Many domestic and foreign experts believe that the most significant oxidizing biocide is the compound halogenated compound formulation combining BCDMH and DBDMH. In agriculture, DBDMH is mainly used for aquaculture including pond disinfection, prevention of water disinfection, disease treatment, etc., and is not affected by water quality, salinity, pH, temperature, and other organic compounds during usage. In addition, there has been already cases in which people has applied DBDMH as high-efficiency and low-toxicity disinfectant for combined formulation with stearic acid monoglyceride and Tween-80 and applied to the surface of the orange for preventing mold and preservation, and has already achieved excellent results. We can expect that this preservative can also be used for storage and preservation of other fruits and vegetables. Therefore, with the continuous development of chemical and pharmaceutical industry and increasing people's living standards, it is expected that the application range and demand of DBDMH will increase greatly.
2. Brominating agent. Analytical reagent for determination of iodide and organic iodine, and for identification tests.
3. It is used for drinking water purification, recreational water treatment, as a bleaching agent in pulp and paper mills, and for treating industrial/commercial water cooling systems. It is an efficient and selective agent for the oxidation of thiols to disulfides in solution or under solvent-free conditions.
Chemical Properties
Different sources of media describe the Chemical Properties of 77-48-5 differently. You can refer to the following data:
1. It appears as white or light yellow crystalline powder.
2. solid
Production method
It is obtained through the bromination of 5, 5-dimethyl hydantoin. Mix the 5, 5-dimethyl hydantoin, sodium carbonate, sodium hydroxide and water together, add bromine slowly under cooling. After the addition, it was poured into water with the crystal filtered out after standing being the crude product. The crude product was further dissolved in acetone for decolorizing and filtrating. The filtrate was poured into water to give white crystalline which is the finished product.
Category
Pesticide
Toxicity grading
Highly toxic
Acute toxicity
Oral-rat LD50: 250 mg/kg.
Flammability and hazard characteristics
It is flammable with burning discharging spicy smoke of bromide and nitrogen oxides.
Storage properties
Warehouse: cold, ventilated and dry; store it separately from food raw materials.
Purification Methods
Recrystallise it from H2O. Its solubility in CCl4 is 0.003 mol/L at 25o and 0.024 mol/L at 76.5o. [Beilstein 24 III/IV 1101.]
Check Digit Verification of cas no
The CAS Registry Mumber 77-48-5 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 7 and 7 respectively; the second part has 2 digits, 4 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 77-48:
(4*7)+(3*7)+(2*4)+(1*8)=65
65 % 10 = 5
So 77-48-5 is a valid CAS Registry Number.
InChI:InChI=1/C5H6Br2N2O2/c1-5(2)3(10)8(6)4(11)9(5)7/h1-2H3
77-48-5Relevant articles and documents
Short inter-molecular N - Br...O=C contacts in 1,3-dibromo-5,5- dimethyl-imidazolidine-2,4-dione
Kruszynski, Rafal
, p. o389-o391 (2007)
In the title compound, C5H6Br2N2O2, all atoms except for the methyl group lie on a mirror plane in the space group Pnma (No. 62). All bond lengths are normal and the five-membered ring is planar by symmetry. Two short inter-molecular N - Br...O=C contacts [Br...O = 2.787 (2) and 2.8431 (19) A] are present, originating primarily from the O-atom lone pairs donating electron density to the anti-bonding orbitals of the N - Br bonds (delocalization energy transfers 3.27 and 2.11 kcal mol-1). The total stabilization energies of the Br...O inter-actions are 3.4828 and 2.3504 kcal mol-1. International Union of Crystallography 2007.
Tail gas treatment process in synthesis process of bromochlorohydantoin
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Paragraph 0037, (2019/07/29)
The invention relates to a tail gas treatment process in the synthesis process of bromochlorohydantoin. The tail gas treatment process includes the first step of taking 5,5-dimethylhydantoin as a rawmaterial to prepare bromochlorohydantoin in a synthesis kettle; leading synthesis kettle tail gas into a tail gas absorption kettle, and evacuating the tail gas absorption kettle through an environmental protection absorption tower; wherein tail gas absorption liquid is disposed in the tail gas absorption tank and is aqueous solution of 5,5-dimethylhydantoin and sodium hydroxide or mixed liquid of5,5-dimethylhydantoin and dibromohydantoin mother solution of sodium hydroxide; leaching absorption liquid is disposed in the environmental protection absorption tower and is sodium hydroxide aqueoussolution and a mixture of sodium hydroxide and dibromohydantoin mother solution; the second step of transferring the tail gas absorption liquid in the tail gas absorption kettle into the synthesis kettle after the synthesis kettle is empty, transferring the leaching absorption liquid in the environmental protection absorption tower into the tail gas absorption kettle, and adding 5,5-dimethylhydantoin. According to the tail gas treatment process, the tail gas generated by the synthesis process of bromochlorohydantoin undergoes two-stage absorption by the tail gas absorption kettle and the environmental protection absorption tower and meets the requirements of environmental protection discharge.
Preparation method of high-stability dibromohydantoin disinfection solution
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Paragraph 0040, (2017/01/12)
The invention provides a preparation method of a high-stability dibromohydantoin disinfection solution. The preparation method comprises the following steps: (1) mixing soluble alkali, 5,5-dimethylhydantoin and water to obtain a water solution; dropping monomer bromine a into the water solution while stirring to obtain a reaction solution; (2) adding a dispersant into the reaction solution obtained in the step (1) and stirring to dissolve the dispersant, and dropping monomer bromine b into the solution to obtain a solution, wherein the mol ratio of the monomer bromine b to the monomer bromine a in the step (1) is 1 to 1, the mass ratio of the dispersant to the reaction solution in the step (1) is (0.01-1) to 100, and the dispersant is one of sodium dodecyl benzene sulfonate, sodium hexadecanesulfonate, sodium octadecyl benzene sulfonate, lauryl sodium sulfate, cetyl sodium sulfate or octadecyl sodium sulfate; and (3) adding a stabilizing agent and a synergist to the solution obtained in the step (2) to obtain a mixed solution, thus obtaining the high-stability dibromohydantoin disinfection solution.
