Hydroxy methylbenzoate

In more recent years, the need to create molecular diversity for peptide libraries has resulted in somewhat of a renaissance for the 4-hydroxy-methylbenzoic acid linkage agent. The ability to cleave the peptide-to-resin ester with many nucleophiles including hydroxide, alkoxides, and primary amines has added to the library workers arsenal. 

In order to remove 1-3 g. of contaminating 2-hydroxy-3-methylbenzoic acid, the crude acid is ground in a mortar and refluxed briefly with 100 ml. of chloroform, and the suspension is filtered hot (Note 9). The separated solid is dried in air and added to 1 1. of boiling water. Fhe mixture is boiled gently for 15 min-... 

Hydroxyisophthalic acid has been prepared by oxidizing 2-hydroxy-3-methylbenzoic acid with lead dioxide, by cleaving the ether group of 2-methoxyisophthalic acid with hydriodic acid, and by hydrolyzing 2-iodoisophthalic acid with alcoholic sodium hydroxide. ... 

Hydroxylamine-O-sulfonic acid for N-amination of pyridine, 43, 1 Hydroxylation of indene, 41, 53 2-Hydroxy-3-methylbenzoic add, oxidation to 2-hydroxyisophthalic acid by lead dioxide, 40, 48 Rydroxymethyleerrocene. 40, 52... 

Methylphenol is carboxylated by a methanogenic consortinm to 4-hydroxy-3-methyl-benzoate that was dehydroxylated to 3-methylbenzoate, which was the stable end product (Bisaillon et al. 1991). 

Roberts DJ, PM Fedorak, SE Hrudey (1990) COj incorporation and 4-hydroxy-2-methylbenzoic acid formation during anaerobic metabolism of m-cresol by a methanogenic consortium. Appl Environ Microbiol 56 472-478. 

Technically important dyes are salicylic acid derivatives that function as chrome mordant dyes for wool. Thus Cl Mordant Blue 1 (6.187) is made by the aldehyde synthesis from 2,6-dichlorobenzaldehyde and 2-hydroxy-3-methylbenzoic (o-cresotinic) acid in concentrated sulphuric acid. Oxidation of the leuco base is achieved by the addition of sodium nitrite. On wool the product, which is isolated as the sodium salt, is a dull maroon colour, changing to a bright blue on treatment with a chromium salt. Some dyes of this type, such as Cl Mordant Violet 1 (6.188), also contain a basic group. This compound is also prepared by the aldehyde route. 

As found by Engman et al. (1999), sodium alkyltelluroates are excellent reagents for the generation of aryl radicals from the corresponding iodides in the dark. Accordingly, l-(2-iodo-phenyl)-l-methyloxirane reacts with two equivalents of sodium 1-butyltelluroate giving 2,3-dihydro-3-hydroxy-3-methylbenzo[( ]tellurophene, which was isolated in 62% yield. The latter was readily converted into 2,3-dihydro-3-methylbenzo[( ]tellurophene on treatment with a catalytic amount of p-toluenesulfonic acid (94% yield Scheme 7.42). 

Pezzuto, J. M., Antosiak, S. K., Messmer, W. M., Slaytor, M. B. and Honig, G. R. 1983. Interaction of the antileukemic alkaloid, 2-hydroxy-3,8,9-trimethoxy-5-methylbenzo[c]phenanthridine (fagaronine) with nucleic acids. Chemistry and Biology Interaction, 43 323-339. 

This does not occur in the case of catalyst and reactants here described. With Bronsted-type catalysis, the reaction between the benzoyl cation, Ph-C" =0, and the hydroxy group in phenol is quicker than the electrophilic substitution in the ring. This hypothesis has been also confirmed by running the reaction between anisole and benzoic acid in this case the prevailing products were (4-methoxy)phenylmethanone (the product of para-C-benzoylation) and methylbenzoate (obtained by esterification between anisole and benzoic acid, with the co-production of phenol), with minor amounts of phenylbenzoate, phenol, 2-methylphenol and 4-methylphenol. Therefore, when the 0 atom is not available for the esterification due to the presence of the substituent, the direct C-acylation becomes the more favored reaction. 

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