Bromo Bromotoluene

An example of this is given in Section IV.63—the conversion of 3-bromo-4-aminotoluene into m-bromotoluene. Another application is to the preparation of. iM.-tribromobenzene (Section IV,72) ... 

Yields of 54% of 2-methoxy-4 -methyl diphenyl ether from -bromotoluene and guaiacol, and 60% of 2-mcthoxy-5-methyl-diphenyl ether from 3-bromo-4-methoxytoluene and phenol, have been obtained by the same method in the laboratory of the submitters,... 

Stock and Baker2 5 9 measured the relative rates of chlorination of a number of halogenated aromatics in acetic acid containing 20.8 M H20 and 1.2 M HC1 at 25 °C and the values of the second-order rate coefficients (103Ar2) are as follows p-xylene (11,450), benzene (4.98), fluorobenzene (3.68), chlorobenzene (0.489), bromobenzene (0.362), 2-chlorotoluene (3.43), 3-chlorotoluene (191), 4-chloro-toluene (2.47), 4-fluorotoluene (9.70), 4-bromotoluene (2.47). Increasing the concentration of the aromatic, however, caused, in some cases, a decrease in the rate coefficients thus an increase in the concentration of chlorobenzene from 0.1 M to 0.2 M caused a 20 % decrease in rate coefficient, whereas with 4-chloro-and 4-bromo-toluene, no such change was observed. 

The relay compound 1025 required for the synthesis of all of these 7-oxygenated carbazole alkaloids was obtained starting from commercially available 4-bromo-toluene (1023) and m-anisidine (840) in two steps and 72% overall yield. Buchwald-Hartwig amination of 4-bromotoluene (1023) with m-anisidine (840) furnished quantitatively the corresponding diarylamine 1024. Oxidative cyclization of 1024 using catalytic amounts of palladium(ll) acetate afforded 3-methyl-7-methoxycarbazole (1025). Oxidation of 1025 with DDQ led to clauszoline-K (98), which, on cleavage of the methyl ether using boron tribromide, afforded 3-formyl-7-hydroxycarbazole (99) (546) (Scheme 5.149). 

Equip a 1 litre three-necked flask with a reflux condenser, a mechanical stirrer, and a cork carrying a dropping funnel and a thermometer which reaches nearly to the bottom of the flask connect the upper end of the condenser to an absorption trap (Fig. II, 8, 1). Place 100 g. of p-bromo-toluene (Section IV,62) in the flask and immerse the latter in an oil bath (colourless oil in a large beaker). Heat the bath until the temperature of the stirred p-bromotoluene reaches 105°. Illuminate the liquid with... 

Trinitrobromotoluene, (02N)3(Br).C6H.CH3 mw 306.04, N 13.73% Only one isomer is described in-the literature 2,4,6-Trinitro-3-bromotoluene, col ndls(from ale), mp 143 4°, sol in ale, insol in liqroin was first prepd by nitrating 2,4-dinitro -5 bromotoluene and later by diazotizing 2,6 -dinitro-3-bromo-4 aminotoluene(Ref 1). Qvist et al(Ref 2) prepd this compd by nitrating the 5-bromo deriv of o-cymene(isopropyltoluene) and also by nitrating 2,4 dinitro-5-bromotoluene(Ref 3). The trinitrobromotoluene is definitely an expl compd although no investigator has reported its expl props... 

By the method above outlined, toluene has been prepared from bromo-benzene, and p-xylene from p-bromotoluene. 

Bromotoluene, AJ97 U-Bromotoluene, AJ98 a-Bromo- -tolunitrile, AL76... 

Bromo-4-aminotoluene m-Bromotoluene (54-69%, pure) Cu powder added. 28... 

The relative reactivities of photodehalogenation of the three dibromobenzenes, the three bromotoluenes, the three bromoanisoles, the three bromophenols and the three iodo-toluenes in hexane have been determined by irradiation under otherwise identical conditions at X > 290 nm and at a > 230 nm377. With the short-wavelength radiation, the dibromobenzenes and the bromoanisoles react fastest, having almost equal reactivity. The bromotoluenes react about three times as slow and the iodotoluenes are somewhat less reactive than their bromo analogues. The bromophenols are very unreactive. At X > 290 nm, the highest yields are observed with the iodotoluenes, as expected on the basis of their absorption spectra. 

Bromo 2 propyne flupropadine Bromo succinimide quinmerac m. Bromotoluene see PCBA... 

SYNS (BROMOMETHYL)BENZENE p-(BROMO-METHYL)NITROBENZENE BROMOPHENYL-METHANE (O-BROMOTOLUENE P [Pg.151]

For the preparation of chlorides or bromides, the diazonium salt is decomposed with a solution of cuprous chloride or bromide in the corresponding halogen acid (Sandmeyer reaction). It is possible to prepare the aryl bromide from the diazonium chloride or sulfate. A variation Involves the use of copper powder and a mineral acid for the decomposition step (Gattermann reaction). Both procedures are illustrated by the syntheses of the isomeric bromotoluenes and chlorotoluenes. The usual conditions of the Sandmeyer reaction fail in the preparation of the chloro- and bromo-phenanthrenes. However, these compounds can be successfully obtained by the interaction of the diazonium compound with mercuric and potassium halides (Schwechten procedure). Another procedure for formation of aryl bromides involves treatment of the amine hydrobromide with nitrogen trioxide in the presence of excess 40% hydro-bromic acid. The Intermediate diazonium perbromide is then decomposed by heat. ... 

The spectra of the intermediate transients formed in the reaction of OH with dichloro- and dibromo-benzenes and chloro- and bromo-toluenes exhibited absorption maxima around 325-330 nm with both ortho- and w to-isomers of dichlorobenzenes, dibromobenzenes, and bromotoluenes (Fig. 6). The transients were assigned to the isomeric OH adducts formed from the addition of OH to the benzene ring. A blue shift was observed in the absorption maximum of -bromotoluene (315 nm) when compared to its ortho- and meta-isomers which have maxima at 330 nm. Such a behavior was also seen in the absorption spectra of OH adducts of 0- and w-chlorotoluenes (325-330 nm) and w-xylenes (326-328 nm) as compared to their... 

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