4-Methyl phenol methylene chloride reaction

Reaction of phenols with BTMABr3 or TBABr3 in a methanol/methylene chloride solvent mixture results in a step-by-step bromination. The degree of bromination depends solely on the molar ratio of reagent to substrate (equation 64)522. With the first mole of reagent / -bromophenol is obtained, followed by 2,4- dibromophenol and, finally, 2,4,6-tribromophenol. The role of methanol in these systems is apparently the in situ formation of methyl hypobromite. The same selectivity is, however, found in chloroform523. 

An effort was made to prepare a butyl analogue containing a ring, but it was never completed. This was the cyclopropylmethyl isomer, 2,5-dimethoxy-4-cyclo-propylmethylamphetamine hydrochloride, DOCPM. Only the first step of its synthesis was complete (the reaction of cyclopropylcarboxylic acid chloride with p-dimethoxybenzene) and even it went badly. The desired ketone (2,5-dimethoxyphenyl cyclopropyl ketone) was most difficult to separate from the recovered starting ether. A promising approach would be the isolation of the phenol (2-hydroxy-5-methoxyphenyl cyclopropyl ketone) which is a beautiful yellow solid with a melting point of 99-100 °C from methanol. Anal. (Cl 1 HI203) C,H. It then could be methylated to the wanted intermediate. It is the major product when the reaction is conducted with anhydrous aluminum chloride in methylene chloride. 

CAS 68610-51-5 EINECS/ELINCS 271-867-2 Synonyms p-Cresol dicyclopentadiene butylated polymer 4-Methyl phenol reaction product with dicyclopentadiene and isobutylene Classification Sterically hindered phenol Definition Butylated reaction prod, of p-cresol and dicyclopentadiene Properties Off-wh. to tan powd. sol. in acetone, ethyl acetate, ethanol, methylene chloride, llq. phosphites insol. in water m.w. 600-700 dens. 1.10 flash pt. (COC) 215 C... 

The first phenolic derivative of ferrocene to be reported, di(l-hy-droxy-3-methyl-cyclopentadienyl) iron, was prepared by the reaction between 3-methyl-2-cyclopentanone, sodamide, and ferrous chloride in liquid ammonia. This compound is remarkably unstable, being extremely sensitive to air. It is a yellow substance which sublimes at 130-140° at 0.1 mm pressure, and is readily soluble in methylene dichloride but insoluble in carbon tetrachloride and in n-heptane. In water saturated with nitrogen a yellow solution is produced which rapidly bec( nes blue-green on exposure to air. The compound forms a benzoate (mp 121-123.5°) which is stable in air. An analogous derivative of the dicyclo-pentadienyl cobalt (III) cation has also been obtained (6). 

Various aromatic amines, phenols, and compounds containing active methylene groups can be titrated with arenediazonium salts, from which 4-bromo-l-naphthale-nediazonium chloride seems to be the most widely applicable titrant. Compounds that react slowly with arenediazonium salts can be determined by back-titration when the excess of arenediazonium salt is back-titrated with either sodium tetraphenylborate or 2,4-diaminotoluene. Indirect determination is useful for secondary amines, which react with arenediazonium ions to form triazenes. The determination of diazonium salts of ampholytic character is based on the reaction of these salts with l-phenyl-3-methyl-5-pyrazolone, the excess of which is titrated with 4-bromo-l-naphthalenediazonium chloride solution. 

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