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Iodine acetate chlorine compounds

Aromatic Ring Reactions. In the presence of an iodine catalyst chlorination of benzyl chloride yields a mixture consisting mostly of the ortho and para compounds. With strong Lewis acid catalysts such as ferric chloride, chlorination is accompanied by self-condensation. Nitration of benzyl chloride with nitric acid in acetic anhydride gives an isomeric mixture containing about 33% ortho, 15% meta, and 52% para isomers (27) with benzal chloride, a mixture containing 23% ortho, 34% meta, and 43% para nitrobenzal chlorides is obtained. [Pg.59]

Redox titrants (mainly in acetic acid) are bromine, iodine monochloride, chlorine dioxide, iodine (for Karl Fischer reagent based on a methanolic solution of iodine and S02 with pyridine, and the alternatives, methyl-Cellosolve instead of methanol, or sodium acetate instead of pyridine (see pp. 204-205), and other oxidants, mostly compounds of metals of high valency such as potassium permanganate, chromic acid, lead(IV) or mercury(II) acetate or cerium(IV) salts reductants include sodium dithionate, pyrocatechol and oxalic acid, and compounds of metals at low valency such as iron(II) perchlorate, tin(II) chloride, vanadyl acetate, arsenic(IV) or titanium(III) chloride and chromium(II) chloride. [Pg.297]

Hofmann found that antimony pentachloride facilitates the action of chlorine on carbon disulphide or ethylene, and so discovered a halogen carrier . H. Muller found that iodine markedly accelerates the action of chlorine on benzene and other compounds, e.g. acetic acid at the boiling-point forms monochloracetic acid antimony pentachloride gives mostly more highly chlorinated compounds. B. Aronheim, at the suggestion of Lothar Meyer, found that molybdenum pentachloride acted in the same way as iodine, and A. G. Page that ferric chloride is also an active chlorine... [Pg.558]

The most important of the halogenated derivatives of acetic acid is chloroacetic acid. Fluorine, chlorine, bromine, and iodine derivatives are all known, as are mixed halogenated acids. For a discussion of the fluorine derivatives see Fluorine compounds, organic. [Pg.87]

Manufacture. Trichloromethanesulfenyl chloride is made commercially by chlorination of carbon disulfide with the careful exclusion of iron or other metals, which cataly2e the chlorinolysis of the C—S bond to produce carbon tetrachloride. Various catalysts, notably iodine and activated carbon, are effective. The product is purified by fractional distillation to a minimum purity of 95%. Continuous processes have been described wherein carbon disulfide chlorination takes place on a granular charcoal column (59,60). A series of patents describes means for yield improvement by chlorination in the presence of dihinctional carbonyl compounds, phosphonates, phosphonites, phosphites, phosphates, or lead acetate (61). [Pg.132]

Treatment of pyrrole, 1-methyl-, 1-benzyl- and 1-phenyl-pyrrole with one mole of A -bromosuccinimide in THF results in the regiospecific formation of 2-bromopyrroles. Chlorination with IV-chlorosuccinimide is less selective (8UOC2221). Bromination of pyrrole with bromine in acetic acid gives 2,3,4,5-tetrabromopyrrole and iodination with iodine in aqueous potassium iodide yields the corresponding tetraiodo compound. [Pg.50]

The natural glucocorticoid is hydrocortisone (cortisol). Semi-synthetic 9a-bromohydrocortisone 21-acetate was found to be less active as an anti-inflammatory agent than hydrocortisone 21-acetate by a factor of three, and 9a-iodohydrocortisone 21-acetate was also less active by a factor of 10. However, 9a-fluorohydrocortisone 21-acetate (fludrocortisone acetate) was discovered to be about 11 times more active than hydrocortisone acetate. Although the bromination sequence shown is equally applicable to chlorine and iodine compounds, fluorine must be introduced indirectly by the P-epoxide formed by base treatment of the 9a-bromo-lip-hydroxy analogue. [Pg.292]

Halogenation of dibenzofuran produces the 2-halo compounds. Bromina-tion can be achieved in good yield with bromine in acetic acid " or with N-bromosuccinimide in boiling carbon tetrachloride. The 2,8-dibromo compound has been made, using dioxane dibromide. Chlorination of dibenzofuran in acetic acid in the presence of iron powder can be controlled to yield the 2-chloro or the 2,8-dichloro compounds. 2-Chlorodi-benzofuran is best prepared by reaction of dibenzofuran with phosphorus pentachloride. 2-Iododibenzofuran (45%) results from treatment of dibenzofuran with iodine in boiling chloroform in the presence of nitric acid. 2,8-Diododibenzofuran is best prepared by reaction of dibenzofuran with iodine and iodic acid in aqueous acetic acid. ... [Pg.67]

Reactions of a number of l-phenylimidazole-2-carboxamides with chlorine in acetic acid, NCS, or hypochlorite failed to introduce chlorine into the 4- or 5-positions (80JHC409). Chlorination of a variety of 2,4-disubstituted imidazoles, however, was quite facile, Thus, 2,4-diesters [83JCS(P1)809] and 2-amino-4-aryl compounds [80IJC(B)526] were readily 5-chlorinated, and even when both the 4- and the 5-positions were blocked, as in 5-aminoimidazole-4-carboxamide, 2-chlorination with iodine monochloride was possible (89MI5). When all three carbons were substituted (e.g., in 2,4,5-triphenyl-, 2-chloro-4,5-diphenyl-, and 2-trichloromethyl-... [Pg.347]


See other pages where Iodine acetate chlorine compounds is mentioned: [Pg.292]    [Pg.12]    [Pg.292]    [Pg.150]    [Pg.272]    [Pg.177]    [Pg.292]    [Pg.627]    [Pg.292]    [Pg.48]    [Pg.314]    [Pg.705]    [Pg.239]    [Pg.163]    [Pg.327]    [Pg.107]    [Pg.122]    [Pg.292]    [Pg.531]    [Pg.176]    [Pg.740]    [Pg.292]    [Pg.341]    [Pg.643]    [Pg.981]    [Pg.97]    [Pg.1188]    [Pg.63]    [Pg.226]    [Pg.343]    [Pg.336]    [Pg.464]    [Pg.609]    [Pg.695]    [Pg.838]    [Pg.839]    [Pg.906]    [Pg.1003]   
See also in sourсe #XX -- [ Pg.114 ]

See also in sourсe #XX -- [ Pg.114 ]




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Acetic chlorination

Chlorinated compounds

Chlorine acetate

Chlorine iodine

Iodinated compounds

Iodine compounds

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