3.5- di-r-butylcatechol

Phenolic inhibitors such as hydroquinone (35), monomethylhydroquinone p-metboxyphenol) (36) and 3,5-di-r-butylcatechol (37) are added to many commercial monomers to prevent polymerization during transport and storage. 

Oxidation of the carbinol (4) with periodate does not give the expected spiro-epoxy compound but the benzaldehyde acetal of 3,5-di-r-butylcatechol (5). This oxidative rearrangement is apparently limited to o-hydroxy-substituted diaryl- and triaryl-carbinols.3... 

Compiled from refs. 24-27. DBCHj, 3,5-di-r-butylcatechol NTAH3, iVJV-bis(carboxymethyl)glycine PDAHj, Af-(2-pyridylmethyl)7V-(carboxymethyl)glycine BPG, iV//-bis(2-pyridylmethyl)glycine TPA, tris(2-pyridiylmethyl)amine. 

Oxidation of catechols Oxidation of catechol itself by KOa is complicated by extensive concomitant polymerization. On the other hand, oxidation of 3,5-di-r-butylcatechol (1) is relatively simple. The first intermediate is the o-benzo-semiquinone as evidenced by the blue color that develops rapidly. An early... 

Acidification of solutions containing [0s02(Rcat)]2+ or direct treatment of the catechol with 0s04 in acetone gives dark blue, polymeric species [OsO(Rcat)2] hH2 O, thought to contain Os—O—Os —O---chains (R-cat = 4-methylcatechol, 4-terf-butylcatechol, 3,5-di-tert-butylcatechol). These are remarkably stable species, unreactive even towards boiling pyridine.4 6... 

Bis(3,4-dicarboxybenzoyl)phthalocyanines with M = Co(II) or Cu(II) have been covalently bound to linear polystyrene by a Friedel-Crafts reaction [130], The polymers contained 0.13 mmol g (12.4 wt.%) phthalocyanine moieties. The sensitivity of the polymers toward toxic gases were investigated by quartz balance transducers. The sensitivities are 6T0" m mL for NO2 and 2T0 m mL for chloroform and perchloroethylene, respectively. 52 (R = SO2CI, M = Fe) has been covalently bound to the amino groups of a cross-linked, hydrophilic polymer consisting of A/ -acryloyl-P-alanine-(aminoethyl-ene)-amide, A -acryloylpyrrolidine and 7V,A -bis(methacryloyl)-l,2-diamino-ethane as comonomers [131]. The polymer obtained, 52, contains 20 pmol phthalocyanine units per g. The catalytic oxidation of 2,4,6-trichlorophenol or 3,5-di-tert-butylcatechol in the presence of H2O2 or KHSO5 as oxidant has been studied. Around 80% of the trichlorophenol was catalytically oxidized within 2 h at pH 7. 

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