Resorcinol Resorcylic acid

Bromoresorcinol may be similarly prepared from /3-resor-cylic acid [27]. To obtain 2-bromo- or 2-chloro-resorcinol, /3-resorcylic acid is successively nitrated and halogenated. The resulting product is then reduced, deaminated, and finally decarboxylated (H2O, 100 , 3hr) to give the desired compound [28]. 

Kluge C, A Tschech, G Fuchs (1990) Anaerobic metabolism of resorcylic acids (m-dihydroxybenzoates) and resorcinol (1,3-benzenediol) in a fermenting and in a denitrifying bacterium. Arch Microbiol 155 68-74. 

Tschech A, B Schink (1985) Fermentative degradation of resorcinol and resorcylic acids. Arch Microbiol 143 52-59. 

The reaction is particularly facile with di- and tri-hydric phenols. Thus p-resorcylic acid is readily obtained by passing carbon dioxide through a boiling aqueous solution of the potassium or sodium salt of resorcinol ... 

Since the nitration of resorcinol by the conventional method for phenols (i.e. sulphonation followed by the action of nitric acid) yields a trinitro derivative, two other methods for the preparation of dinitroresorcinol are possible, viz. oxidation of dinitrosorcsorcinol or nitration of resorcylic acid followed by decarboxylation. 

Resacetophenone, 21,103 Resorcinol, 21, 23, 103 27, 21 cx-Resorcylic acid, 21, 27 Ring opening by hydrolysis with barium hydroxide, 22, 91 Rosenmund synthesis, aldehyde, 21, 84, 110... 

The nmr chemical shifts of alkah metal ( K, Na etc.) phenoxide moved to down field upon formation of the complex, [ phenoxide-M CO2] with carbon dioxide in the Kolbe-Schmitt reaction. The complex formed under pressure of carbon dioxide showed more increments in weights and chemical shifts, as much as 0.72 ppm of (5 paia of potassium phenoxide at 5 MPa. The kinetic studies on the carboxylation of resorcinol in aqueous hydrogencarbonates with carbon dioxide revealed an equilibrium between resorcinol and the product or resorcylic acid. 

The rate of the formation of /3 -resorcylic acid (RA) was a first order with respect both to ROH and to KHCOi. The overall reaction rate with bubbling carbon dioxide gas into the aqueous solution of potassium hydrogencarbonates is d[resorcylic acidj/dt = ki[resorcinol][KHCO,d + k2[resorcinol][pC02] ( 1)... 

Phenols that have more than one hydroxyl group may be carboxylated with CO2 at atmospheric pressure under basic conditions. The research team of Y.-C. Gao synthesized 3,5-di-fert-butyl-y-resorcylic acid from 4,6-di-fert-butyl resorcinol using the Kolbe-Schmitt reaction under these conditions. The resorcylic acid derivative was needed in order to prepare ternary complexes of lanthanide(lll)-3,5-di-fert-butyl-Y-resorcylate with substituted pyridine-A/-oxide. 

Carboxylation of resorcinols. The acidity of the aromatic hydrogens in resorcinols prompted Israeli chemists4 to investigate the possibility of carboxylation with magnesium methyl carbonate. The reaction was successful. Thus resorcinol gave /3-resorcylic acid (45%) and 2,4-dihydroxyisophthalic acid (15%), together with starting material (43%). 

As examples, / - and y-resorcylic acid afford resorcinol readily when boiled with water.30... 

Also obtained by photo-Fries rearrangement of resorcinol monobenzoate [219], Preparation by reaction of di(carbomethoxy)-P-resorcylic acid chloride with benzene in the presence of aluminium chloride at 60-70° for 1 h, then at 80° for 1 h (70%) [220],... 

Preparation by reaction of p-resorcylic acid with resorcinol,... 

Also obtained by action of P-resorcylic acid with resorcinol in the presence of zinc chloride for 45 min at 125-140° [1505]. 

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