IODO-p-XYLENE

Iodo-p-xylene has been prepared by the action of potassium iodide on diazotized p-xylidine (2,5-dimethylbenzenamine) (21% yield),5 from p-xylene with molecular iodine in concentrated nitric acid (50% yield)6 or in ethanol-sulfuric acid in the presence of hydrogen peroxide (64% yield),7 and with molecular iodine in glacial acetic acid-sulfuric acid in the presence of iodie acid as a catalyst (85% yield).8... 

Aryl iodides (3, 287 4, 498). Details for the preparation of 2-iodo-p-xylene (equation I) have been published. Use of freshly prepared TTFA rather than commercial material is recommended. ... 

A soln. of 0.24 mole of p-xylene in acetic acid treated at 80° with water until the soln. turns turbid, coned. H2SO4, 0.15 g.-atom iodine, 0.04 mole of iodic acid, and CGI4 added, vigorously stirred ca. 4 hrs. until the iodine color disappears 2-iodo-p-xylene. Y 85%.—Similarly at 40° Veratrole 4-iodoveratrole. Y 88%.—Thiophene 2-iodothiophene. Y 75%, F. e. and discussion of the... 

Iodovanillin, 164 4-Iodoveratrole, 495,1018-1019 lodoxybenzene, 488-489, 511,1085 2-Iodo-1,4-xylene, 496 Ion-exchange resins, 332, 473, 511-519 lonol, see 2,6-Di-r-butyl-p-cresol /3-Ionone, 573 2 Ionylidene-ethanol, 637... 

Restricted Internal Rotation of Several Symmetric Tops. The tables of thermodynamic functions for an internal rotation of a single symmetric top may be used for several symmetric tops [with moments of inertia calculated from equation (20)] provided both potential energy and kinetic energy cross-terms between the tops can be neglected. Both assumptions have been generally made in calculations for molecules with several tops. Where there are reliable calorimetric data at one or more temperatures, the tables have been used to calculate appropriate potential barriers. Using this procedure thermodynamic contributions have been calculated for propane, 2-methylpropane, 2,2-dimethylpropane, cis-but-2-ene, rm a -but-2-ene, isobutene, o-xylene, > m-xylene, p-xylene, 1,2,3-trimethylbenzene, > 1,2,4-trimethylbenzene, dimethyl sulphide,2-chloro-2-methylpropane, and dimethyl-amine. In several cases thermodynamic contributions have been calculated using potential barriers estimated from those of related molecules. Examples of this procedure are found in calculations for 2-fluoro-2-methylpropane, 2-chloropropane, 2-bromopropane, 2-iodopro-pane, 2,2-dichloropropane, 2-bromo-2-methylpropane, 2-iodo-2-methylpropane, 1,3,5-trimethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1,2,3,4-tetramethylbenzene, pentamethyl-benzene, and hexamethylbenzene. ... 

The intramolecular enantioselective aminofluorination of unactivated olefins, such as (1), has been attained by using the chiral iodo(III) difluoride (5) with <88% ee (Scheme 1). The reaction is believed to proceed via an intramolecular aziridination (1) (2) - (3), followed by a nucleophilic attack with to produce (4). A regio-selective aminofluorination of styrenes ArCH=CH2 with p-xylene IFj and TsNHR... 

Synonyms Perfluoro-n-hexyl sulfonic acid Empincal CeHFisOsS Formula CF3(CF2)sS03H Properties M.w. 400.11 Uses Fire extinguishant additives Perfluorohexyl iodide CAS 355-43-1 EINECS/ELINCS 206-586-6 Synonyms Hexane, 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluoro-6-iodo- 1-lodoperfluorohexane 1-lodotridecafluorohexane Perfluoro-n-hexyl iodide Perfluoro-1-iodohexane Tridecafluorohexyl iodide Tridecafluoro-1-iodohexane 1,1,1,2,2,3,3,4,4,5,5,6,6-Tridecafluroo-6-iodohexane Empirical CeFisI Formula CF3(CF2)4CF2l Properties Colorless liq. which can turn rosy or violet sol. > 250 g/l in ethanol, acetone, ethyl acetate, xylene, hexane, tetrahydrofuran, dimethylformamide, dimethylsulfoxide, trichlorotrifluoroethane, chloroform insol. in water m.w. 445.95 sp.gr. 2.051-2.063 m.p. -45 C b.p. 

The presence of iodine is known to catalyse the chlorination of organic compounds by chlorosulfonic acid, enabling the reaction to proceed under comparatively mild conditions. So chlorination is a feature of the attempted sulfonation of aromatic iodo compounds with chlorosulfonic acid (see Chapter 2, p 19) for instance, reaction of />-diiodobenzene with excess reagent (five equivalents) at 50 C yields tetrachlorodiiodobenzene (82%), (Chapter 6, ref. 13). The chlorination is catalysed by traces of iodine and the reaction under these conditions probably involves both homolytic and heterolytic steps (see Chapter 4, p 49). Hexachloro-/7-xylene, by treatment with a mixture of chlorosulfonic acid, iodine and chlorine afforded either the 2,5-dichloro derivative or tetrachloro-terephthaloyl chloride depending on the experimental conditions (see Chapter 4, p 51). 

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