Hydrochloric Acid → Benzenesulfinic acid, 4-methyl-, methyl ester

Participants

Reaction Conditions

Reaction Steps

To a 5-liter, 3-neck round bottom flask, was added 2845 mls of methanol (5 volumes) and was bubbled in 165.58 grams (1.4 equivalents, 4.47 gmoles) of anhydrous HCl. Heat evolved during addition of HCl to MeOH. The flask was maintained at a temperature range from 20 to 25° C. by cooling and adjusting addition rate. Sodium toluene sulfinic acid (1.0 equivalents, 569 grams, 3.19 gmoles) was added and stirred at room temperature for 1 to 4 hours. Water 2850 mls (5 volumes) was added, then and 2850 mls of toluene (5 volumes.) The mixture was stirred from 1 to 30 minutes and the layers were allowed to separate The layers were separated and the aqueous layer was back extracted twice using 1425 mls (2.5 volumes) of toluene for each back extraction. All toluene layers were combined and washed two times with 1425 mls (2.5 volumes) of 1 molar sodium bicarbonate solution for each wash. The layers were separated and the toluene layerers was concentrated under vacuum to approximately 3 volumes. The volumes were concentrated to a small alloquote to an oil on rotovap indicated a final weight yield of 476.78 grams of ester, 87.7% of theory weight.

Provenance & Evidence