Catechol sulfate

CycHc esters show accelerated hydrolysis rates. Ethylene sulfate compared to dimethyl sulfate is twice as fast ia weak acid (first order) and 20 times as fast ia weak alkaH (second order) (50). Catechol sulfate [4074-55-9] is 2 x 10 times faster than diphenyl sulfate ia alkaline solution (52). Alcoholysis rates of several dialkyl sulfates at 35—85°C are also known (53). 

Catechol sulfates are efficiently synthesized by reacting the appropriate catechol with AyV -sulfonyldiimidazole in the presence of potassium fluoride [33]... 

Cyclic five-membered sulfates and sultones are known to undergo hydrolysis from 105 to 107 faster than their acyclic analogs. Thus, for example, catechol sulfate [54] undergoes alkaline hydrolysis 2 x 107 faster than diphenyl sulfate (Kaiser et al., 1965), and l-naphthol-8-sulfonic acid sultone [55] hydrolyzes 5 x 105 faster than phenyl cr-toluenesulfonate (Kaiser et al., 1967). In contrast... 

Most compounds of this type are cyclic sulfite and sulfate esters of aromatic 1,2-diols as well as anhydrides of aromatic 1,2-disulfonic acids. The simplest representatives with unsubstituted benzene rings are 1,3,2-benzodioxathiole 2-oxide (48) (catechol sulfite), the corresponding 2,2-dioxide (156) (catechol sulfate) and 2,1,3-benzoxadithiole 1,1,3,3-tetroxide (158) (1,2-benzenedisulfonic anhydride). Compound (48) was synthesized by refluxing catechol with thionyl chloride in the presence of pyridine. In a similar fashion, from 2-mercaptophenol 1,2,3-benzoxadithiole 2-oxide was prepared (81AG603). The dioxide (156) was obtained in two steps by reaction of catechol monosodium salt with sulfuryl chloride in benzene at 0-10 °C and subsequent reflux of the intermediate (155) in the presence of pyridine. 

Sulfamide (136) can be prepared by reaction of sulfuryl chloride (128) with excess ammonia in dichloromethane at -50°C, followed by extraction of the product with acetonitrile (Scheme 55). By using primary amines in the condensation, the method can be extended to obtain N,N -disubstituted sulfamides (137) (Scheme 55). A valuable route to di- and trisubstituted sulfamides involves the reaction of catechol sulfate (138) with aniline. Aniline reacts slowly with (138) to give the sulfamoyl ester (139). The unreacted aniline then promotes base-catalysed elimination of catechol to form the transient, highly reactive N-phenylsulfonylimine (140) which is trapped by aniline to yield N,N -diphenylsulfamide (141). By reaction of the ester (139) with an alkylamine, the procedure can be used to obtain trisubstituted sulfamides (142) (Scheme 56). In general, the amination of the 2-hydroxyphenyl sulfamate esters using alkylamines is an efficient route for the synthesis of trialkylsulfamides (143) (Scheme 57). 

Reaction of this polymer with methylene-imidazole (or chloromethyl-imidazole) leads to a 15% incorporation of imidazole ring on the polymer backbone. Hydrolysis of phenolic sulfate esters (catechol sulfate) was studied and accelerations of 10 -fold, compared to unbound imidazole, were obtained This remarkable macromolecular catalyst, possessing a high local... 

METHOD 1 [112l-5g phenol in dH20 is stirred 5 hours at 20 C with some ferric sulfate (Fe2(S04)3, an additional 7mLs dH20, 13mLs 6% H2O2 and a pinch of aluminum oxide (AI2O3). Yield of catechol is 2.5g (50%). 

The properties of 1,1-dichloroethane are Hsted ia Table 1. 1,1-Dichloroethane decomposes at 356—453°C by a homogeneous first-order dehydrochlofination, giving vinyl chloride and hydrogen chloride (1,2). Dehydrochlofination can also occur on activated alumina (3,4), magnesium sulfate, or potassium carbonate (5). Dehydrochlofination ia the presence of anhydrous aluminum chloride (6) proceeds readily. The 48-h accelerated oxidation test with 1,1-dichloroethane at reflux temperatures gives a 0.025% yield of hydrogen chloride as compared to 0.4% HCl for trichloroethylene and 0.6% HCl for tetrachloroethylene. Reaction with an amine gives low yields of chloride ion and the dimer 2,3-dichlorobutane, CH CHCICHCICH. 2-Methyl-l,3-dioxaindan [14046-39-0] can be prepared by a reaction of catechol [120-80-9] with 1,1-dichloroethane (7). 

Wash with cone H2SO4, then Na2C03 soln, dry with anhydrous Na2C03, and finally pass through a 50cm column of activated alumina before distn. Alternatively, wash with 10% ferrous sulfate soln to remove peroxides, then H2O, dry with CaS04, and dist in vac. Add 0.2% of catechol to stabilise it. VERY TOXIC. 

Kondo maintained his interest in this area, and with his collaborators [62] he recently made detailed investigations on the polymerization and preparation of methyl-4-vinylphenyl-sulfonium bis-(methoxycarbonyl) meth-ylide (Scheme 27) as a new kind of stable vinyl monomer containing the sulfonium ylide structure. It was prepared by heating a solution of 4-methylthiostyrene, dimethyl-diazomalonate, and /-butyl catechol in chlorobenzene at 90°C for 10 h in the presence of anhydride cupric sulfate, and Scheme 27 was polymerized by using a, a -azobisi-sobutyronitrile (AIBN) as the initiator and dimethylsulf-oxide as the solvent at 60°C. The structure of the polymer was confirmed by IR and NMR spectra and elemental analysis. In addition, this monomeric ylide was copolymerized with vinyl monomers such as methyl methacrylate (MMA) and styrene. 

Pure cultures growing anaerobically with catechol and sulfate were isolated,and the carboxylation of catechol was proposed to be the initial reaction of anaerobic catechol degradation by Desulfobacterium sp. strain Cat2. Zhang and Young" proposed that the initial key reaction for anaerobic degradation of naphthalene and phenanthrene was also carboxylation. 

Szewzyk R, N Pfennig (1987) Complete oxidation of catechol by the strictly anaerobic sulfate-reducing Desulfobacterium catecholicum sp. nov. Arch Microbiol 147 163-168. 

Kuever J, J Kuhner, S Janssen, U Eischer, K-H Blotevogel (1993) Isolation and characterization of a new spore-forming sulfate-reducing bacterium growing by complete oxidation of catechol. Arch Microbiol 159 282-288. 

Benzaldehyde, suitable for this synthesis, is purified in the following way. A 60-g. (58-ml.) sample is washed with two 20-ml. portions of 10% sodium carbonate and then with water. It is then dried over 5-10 g. of anhydrous magnesium sulfate. A few small crystals of hydroquinone or catechol are added with the drying agent. The dry benzaldehyde is decanted through a cotton plug into a Claisen flask it is distilled under reduced pressure, preferably below 30 mm. 

Cytochrome P4502E1, also microsomally located, catalyzes the hydroxylation of phenol to form hydroquinone (and to a much lesser extent catechol), which is then acted upon by the phase II enzymes (Benet et al. 1995 Campbell et al. 1987 Gut et al. 1996 McFadden et al. 1996). All three enzyme systems are found in multiple tissues and there is competition among them not only for phenol but for subsequent oxidative products, like hydroquinone. As a consequence, the relative amount of the products formed can vary based on species, dose and route of administration. In vivo, the gastrointestinal tract, liver, lung, and kidney appear to be the major sites of phenol sulfate and glucuronide conjugation of simple phenols (Cassidy and Houston 1984 Powell et al. 1974 Quebbemann and Anders 1973 ... 

Hydroxylamine Sulfate Diethylene Glycol Beta-Propiolactone Nitrogen Tetroxide Ethylene Oxide Benzophenone Benzophenone Diethylene Glycol Oxygen, Liquefied Dibenzoyl Peroxide Catechol Cresols... 

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