Citric Acid → HCID 10018437, compound

Participants

Reaction Conditions

Reaction Steps

To a reaction vessel equipped with a mechanically driven agitator, water-cooled condenser, addition funnel, thermometer, and nitrogen inlet was added 80 cc. of anhydrous diethyl ether of diethylene glycol and 8 g. (0.35 mole) of freshly cut sodium pieces. The mixture was cooled to -2° C. and a solution of 52.4 g. (0.16 mole) of hexamethylditin in 80 cc. of anhydrous diethyl ether of diethylene glycol was added over 20 minutes. The hazy green mixture was stirred for one additional hour at 0° C. and then allowed to warm to room temperature over three hours. The mixture was filtered and then added dropwise over a 2.5 hour period to a solution of 36.6 g. (0.16 mole) ethyl-p-bromobenzoate in 160 cc. of the diethyl ether of diethylene glycol, cooled to -15° C. The solution was stirred 2 hours at -2° C. and 16 hours at room temperature. The solution was then hydrolyzed using 300 cc. of a 5% aqueous citric acid solution. The water phase was separated from the organic phase and washed twice with 200 cc. portions of ether. The organic layers were combined, dried over a quantity of magnesium sulfate, and concentrated under reduced pressure. The solvent was removed at 50 mm. pressure (mercury manometer) and the residue distilled at 0.15 mm. A clear liquid fraction boiling at 88°-90° C. was isolated and analyzed. The tin content was found to be 37.54%. The calculated tin content for carbethoxyphenyltin is 37.92%. Gas chromatographic analysis indicated a purity of 97.6%. The refractive index was recorded as 1.5362 at 23° C. The nuclear magnetic resonance spectrum contained a singlet at 0.38 ppm. (CH3 --Sn, 9H's), a triplet at 1.46 ppm. (CH3 --,3H's), a quartet at 4.50 ppm. ##STR5## and a doublet of doublets at 7.86 ppm. ##STR6##

Provenance & Evidence