- Short inter-molecular N - Br...O=C contacts in 1,3-dibromo-5,5- dimethyl-imidazolidine-2,4-dione
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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.
- Kruszynski, Rafal
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- Enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral phosphine oxide-Sc(OTf)3 complex. A dramatic additive effect
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An effective enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral phosphine oxide-Sc(OTf)3 complex is described. A wide variety of optically active 5-bromo-1,3-oxazinan-2-ones containing various functional groups can be obtained in 61-91% yields and 92-99% ees. An additive, such as NaCl, has been found to be crucial for the reaction process.
- Huang, Hu,Pan, Hongjie,Cai, Yudong,Liu, Mao,Tian, Hua,Shi, Yian
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- Tail gas treatment process in synthesis process of bromochlorohydantoin
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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.
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Paragraph 0037
(2019/07/29)
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- PROCESS FOR THE PREPARATION OF ORGANIC BROMIDES
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The present invention provides a process for the preparation of organic bromides, by a radical bromodecarboxylation of carboxylic acids with a bromoisocyanurate.
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Paragraph 00114-00115;
(2017/07/28)
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- Preparation method of high-stability dibromohydantoin disinfection solution
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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.
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Paragraph 0040
(2017/01/12)
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- Process for producing N-halogenated organic compounds
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The process enables highly effective N-halogenation of a compound having one or more halogenatable amido or imido functional groups in the molecule. The process involves, for example, concurrently feeding into a reactor (i) water, inorganic base, and the compound to be N-halogenated, e.g., a hydantoin, and a feed of (ii) a brominating agent and/or a chlorinating agent. The proportions of these feeds are such that the pH is kept at 5 or below or within a specified range e.g., 5.5-8.5 and one or more of the amido or imido nitrogen atoms is substituted by a bromine or chlorine atom. A feature of the process is that it can be conducted at elevated temperatures as high as about 90° C. without appreciable thermal decomposition of reactants or product. The resultant product continuously precipitates in high yield and purity. Moreover, products can be produced that are very pale yellow to almost pure white in appearance. Further, the process has been found capable of producing 1,3-dibromo-5,5-dimethylhydantoin with far larger particle sizes than previously produced on a commercial basis.
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- Process for producing N-halogenated organic compounds
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The process enables highly effective N-halogenation of a compound having one or more halogenatable amido or imido functional groups in the molecule. The process involves, for example, concurrently feeding into a reactor (i) water, inorganic base, and the compound to be N-halogenated, e.g., a hydantoin, and a feed of (ii) a brominating agent and/or a chlorinating agent. The proportions of these feeds are such that the pH is kept within the range of ca. 5.5-8.5 (preferably 6.5-8.5, and most preferably 6.8-7.2) and one or more of the amido or imido nitrogen atoms is substituted by a bromine or chlorine atom. A feature of the process is that it can be conducted at elevated temperatures as high as about 90° C. without appreciable thermal decomposition of reactants or product. The resultant product continuously precipitates in high yield and purity. Moreover, products can be produced that are very pale yellow to almost pure white in appearance. Further, the process has been found capable of producing 1,3-dibromo-5,5-dimethylhydantoin with far larger particle sizes than previously produced on a commercial basis.
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- Particulate blends and compacted products formed therefrom, and the preparation thereof
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The dry blends comprise a powdery or finely-divided active ingredient such as a pharmaceutical, dietary supplement, agricultural chemical, water-treating agent or biocidal agent, and a micronized synthetic polyolefin-based hydrocarbon wax and/or a micronized synthetic polyfluorocarbon wax that is compatible with the active ingredient. Shape-retentive compacted compositions are formed by pressure compacting such blends. Preferred active ingredients are 1,3-dihalo-5,5-dialkylhydantoins and profen pharmaceuticals such as naproxen.
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- Liquid deodorant killing microorganism and method of microorganism-killing deodorization
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The object of the present invention is to provide a microbicidal deodorant in a tractable liquid form that has excellent long-term storage stability. The microbicidal deodorant of the present invention comprises: at least one substance selected from the group consisting of halogenated dialkyl hydantoins represented by general formula (1) and halogenated succinimides represented by general formula (2); and at least one substance selected from the group consisting of tetrahydrothiophene 1,1-dioxide, 3-methyltetrahydrothiophene 1,1-dioxide, and 2,5-dihydrothiophene 1,1-dioxide.
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- Methods for microbiological control in aqueous systems
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Microbiological control in aqueous media and/or eradication or reduction of biofilm on a surface in contact with such media is achieved by introducing into the aqueous medium a microbiocidally effective quantity of one or more 1,3-dibromo-5,5-dialkylhydantoins where one of the alkyls is methyl and the other is a C1-4alkyl, wherein (i) the molar quantity of 1,3-dibromo-5,5-dialkylhydantoin introduced is less than the molar quantity of N,N′-bromochloro-5,5-dimethylhydantoin that would be required to effect the same degree of microbiological control in that medium, (ii) the molar quantity of the 1,3-dibromo-5,5-dialkylhydantoin introduced releases an amount of “free chlorine” that is greater than the amount of “free chlorine” that would be released in that medium by an equimolar quantity of N,N′-bromochloro-5,5-dimethylhydantoin, and (iii) the amount of “free chlorine” released by the quantity of the 1,3-dibromo-5,5-dialkylhydantoin introduced is greater than the amount of “free chlorine” that could be predicted to be released by that quantity of 1,3-dibromo-5,5-dialkylhydantoin on the basis of the amount of “free chlorine” that would be released in that medium by an equimolar quantity of N,N′-bromochloro-5,5-dimethylhydantoin.
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- Microbiological control in aqueous systems
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Microbiological control is achieved by continuously and inexpensively dosing water in contact with biofilm, or that comes into contact with biofilm, using a highly effective biocide that provides very effective microbiocidal control of planktonic microorganisms and of biofilm species, even where the biofilm infestations have been in existence for long periods of time and thus have encased themselves in a substantial quantity of slimy defensive polysaccharide layers or films. In addition, the biocide used makes possible significant reduction in copper and/or iron surfaces in contact with the water as compared to N,N′-bromochloro-5,5-dimethyl hydantoin. Still other advantages are made possible by the described technology.
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- PARTICULATE BLENDS AND COMPACTED PRODUCTS FORMED THEREFROM, AND THE PREPARATION THEREOF
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The dry blends comprise a powdery or finely-divided active ingredient such as a pharmaceutical, dietary supplement, agricultural chemical, water-treating agent or biocidal agent, and a micronized synthetic polyolefin-based hydrocarbon wax and/or a micronized synthetic polyfluorocarbon wax that is compatible with the active ingredient. Shape-retentive compacted compositions are formed by pressure compacting such blends. Preferred active ingredients are 1,3-dihalo-5,5-dialkylhydantoins and profen pharmaceuticals such as naproxen.
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- Microbiological control in aqueous systems
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Biocidally-active 1,3-dibromo-5,5-dialkylhydantoin biocidal compositions in readily identifiable forms are provided in the form of an article of manufacture comprising a packaging material and a biocidal composition contained within said packaging material, wherein said biocidal composition comprises as the biocidally-active component of the biocidal composition (A) at least one 1,3-dibromo-5,5-dialkylhydantoin in which one of the alkyl groups in the 5-position is a methyl group and the other alkyl group in the 5-position contains in the range of 1 to 4 carbon atoms (DBDAH) as the sole biocidally-active ingredient of the composition, or (B) a combination of (i) DBDAH and (ii) at least one non-fluid biocidally-active water treating agent compatible with DBDAH, wherein the weight ratio of (i) to (ii) is in the range of 0.1:0.4 to 99.9:0.1, preferably in the range of 1:1 to 99.9:0.1, more preferably in the range of 9:1 to 99.9:0.1, and most preferably in the range of 19:1 to 99.9:0.1. Each such category of biocidally-active component or components can be, and preferably is in admixture with from 0 to 90 wt % of biocidally-inactive components such as for example one or more binders, fillers, excipients, dyes or colorants, perfumes, stabilizers, and/or manufacturing by-products. The packaging material comprises at least a label suitably identifying the name of the product in the package, and at least a sticker identifying the contents as being an oxidizing agent. The label or another label associated with the packaging material preferably contains other specified information.
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Page column 11-15
(2008/06/13)
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- Microbiological control in aqueous systems
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Microbiological control is achieved by continuously and inexpensively dosing water in contact with biofilm, or that comes into contact with biofilm, using a highly effective biocide that provides very effective microbiocidal control of planktonic microorganisms and of biofilm species, even where the biofilm infestations have been in existence for long periods of time and thus have encased themselves in a substantial quantity of slimy defensive polysaccharide layers or films. In addition, the biocide used makes possible significant reduction in copper and/or iron surfaces in contact with the water as compared to N,N′-bromochloro-5,5-dimethyl hydantoin. Still other advantages are made possible by the described technology.
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- Process for the preparation of pure thiophene derivatives
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3-substituted thiophene compounds contaminating the analogous 2-substituted thiophene compounds, e.g. 3-acetylthiophene contaminating 2-acetyl thiophene, are removed by a selective electrophilic substitution process, e.g. bromination, followed by fractional distillation. It has been found that electrophilic substitution as exemplified by bromination is highly selective towards the 3-substituted thiophenes, yielding compounds of significantly higher molecular weights for separation purposes, to give high purity 2-substituted thiophene compounds.
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- Organic Synthesis Using Sodium Bromate. II. A Facile Synthesis of N-Bromo Imides and Amides Using Sodium Bromate and Hydrobromic Acid (or Sodium Bromide) in the Presence of Sulfuric Acid
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The reaction of imides and amides in water (or aqueous acetic acid) with sodium bromate and hydrobromic acid (or sodium bromide) in the presence of sulfuric acid under mild conditions gave the corresponding N-bromides in high yields.
- Fujisaki, Shizuo,Hamura, Satoshi,Eguchi, Hisao,Nishida, Akiko
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p. 2426 - 2428
(2007/10/02)
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- Process for the preparation of 24,24-difluoro-1α,25-dihydroxy vitamin D3 and intermediates obtained therefrom
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The present invention relates to a process and intermediates for the preparation of 24,24-difluoro-1α,25-dihydroxycholecalciferol from the readily-available 1α,3β-dihydroxyandrost-5-en-17-one which is made by a known microbiological process from 3β-hydroxyandrost-5-en-17-one [R. M. Dodson, A. H. Goldkamp and R. D. Muir, J. Amer. Chem. Soc. 82 4026 (1960)].
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