Toluenes, bromo fluoro

Toluenes substituted with chloro, bromo, fluoro, or cyano groups can be dichlorinated or dibrominated and the resulting benzal halides hydrolyzed directly to the corresponding aldehydes in the presence of calcium carbonate or sulfuric acid (50-70%). o- and p-Xylene have been converted to the corresponding dialdehydes. ° In the halogenation of certain cresols, the carbonate or acetate esters are used in order to prevent nuclear halogenation. ... 

Other examples of preferential sulfonylation at 0-2 are known methanesulfonylation of 8-bromoguanosine gave 8-bromo-2, 5 -di-0-(methylsulfonyl)guanosine in 42% yield, and unimolar p-toluene-sulfonylation of 5-fluoro-5 -0-trityluridine gave 5-fluoro-2 -0-p-... 

Halogen substituted toluenes are readily converted into nitriles because electron-withdrawing substituents enhance the reactivity of such compounds in the ammoxidation reaction. The fluoro-, chloro-, bromo-, and iodo-substituted toluenes [e. g. 41,74-76] can, therefore, be converted to the corresponding nitriles. Whereas the conversion rate of /7-halotoluenes (over vanadium phosphate catalysts [41,75]) is nearly independent of the nature of the halogen substituent, the selectivity decreases in the sequence p-Cl > /7-Br >> p-l. Ammoxidation of isomeric chloro-toluenes results in different conversion p o > m) and selectivity p > o > m) sequences [41,75,76]. 

The particular value of the method is for converting methyl and polymethyl derivatives of polycyclic aromatic compounds into mono- and poly-carboxylic acids. For instance, 1-methylnaphthalene with a 42% excess of aqueous sodium dichromate solution in an autoclave at 240-250° gives 95% of 1-naphthoic acid in 18 h 2-methylnaphthalene with a 55% excess gives a 93% yield of 2-naphthoic acid the methyl group in fluoro-, bromo-, chloro-, nitro-, and methoxy-toluene as well as in xylenes and heterocycles can usually be oxidized smoothly to a carboxyl group. An excess of Na2Cr207 acts as a buffer and favors smooth reaction. With 1.5 moles of Na2Cr207 the reaction occurs in accord with the equation ... 

Bromo-2-fluoro biphenyl intermediate, foam builders Alkenyl succinic anhydride intermediate, food additives Soy acid Stearyl alcohol intermediate, food emulsifiers Caprylic/capric acid Tallow acid intermediate, food supplements (tablet form) Cetyl alcohol intermediate, food wrap Vinylidene chloride monomer intermediate, fragrances p-t-Butyl toluene t-Butyl-m-xylene Citral Cyclopentanone Diethyl toluene diamine Dimethyl hexynediol 1,2-Methylenedioxybenzene 2-Methylpentanal Myrcene n-Propyl bromide intermediate, fragrances cosmetics Acetic anhydride n-Butyraldehyde n-Butyric acid Butyric anhydride 2-Ethylhexoic acid Isobutyric anhydride 2-Methylpropanal Propionic anhydride intermediate, fragrances personal care Butyric anhydride Isobutyric anhydride intermediate, free-radical polymerization initiators... 

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