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Hello I came across this synthesis because several people are convinced of its effectiveness in isomeric separation wanted to share it. There are also photos, unfortunately they could not be inserted.
Devices:
50 mL round flask, 500 mL round flask, reflux cooler, magnetic stirrer with oil bath, vacuum filtration option, drying oven (optional), distillation bridge or rotary evaporator (optional)
Chemicals:
L-(+)-tartaric acid
D-(-)-tartaric acid
Benzoyl chloride
Diethyl ether
Toluene
Acetone
Note: Be careful when handling hot benzoyl chloride.
Performance:
2,3-Dibenzoyl tartaric anhydride:
10 g of enantiomerically pure tartaric acid (D-(−)- or L-(+) tartaric acid) is presented in 27 mL of benzoyl chloride and heated to 130 °C until solidified. It is heated until the contents of the piston can no longer be stirred (approx. 1-3 h). After cooling to room temperature, the solid is suspended in approx. 20 mL diethyl ether, filtered and washed with diethyl ether (2x15 mL). Subsequently, toluene is recrystallized (approx. 200 mL), washed with toluene and dried in a drying oven at 140 °C
dried to mass constancy.
Yield (2,3-dibenzoyl-L-tartaric anhydride): 20.0 g (88% d.Th.)
Yield (2,3-dibenzoyl-D-tartaric anhydride): 17.4 g (76% d.Th.)
2,3-Dibenzoyl tartaric acid:
2,3-dibenzoyl tartaric anhydride is suspended in a 500 mL flask in a mixture of 100 mL acetone and 50 mL water and heated to a boil for one hour. The acetone is distilled and the resulting emulsion is filled with water to 400 mL. It is heated to a boil for 15 min and the mixture is cooled to room temperature, stirring vigorously, precipitating a white solid. It is filtered, washed with water and dried in the desiccator over calcium chloride.
((−)-2,3-dibenzoyl-L-tartaric acid):
((+)-2,3-dibenzoyl-D-tartaric acid):
Hello I came across this synthesis because several people are convinced of its effectiveness in isomeric separation wanted to share it. There are also photos, unfortunately they could not be inserted.
Devices:
50 mL round flask, 500 mL round flask, reflux cooler, magnetic stirrer with oil bath, vacuum filtration option, drying oven (optional), distillation bridge or rotary evaporator (optional)
Chemicals:
L-(+)-tartaric acid
D-(-)-tartaric acid
Benzoyl chloride
Diethyl ether
Toluene
Acetone
Note: Be careful when handling hot benzoyl chloride.
Performance:
2,3-Dibenzoyl tartaric anhydride:
10 g of enantiomerically pure tartaric acid (D-(−)- or L-(+) tartaric acid) is presented in 27 mL of benzoyl chloride and heated to 130 °C until solidified. It is heated until the contents of the piston can no longer be stirred (approx. 1-3 h). After cooling to room temperature, the solid is suspended in approx. 20 mL diethyl ether, filtered and washed with diethyl ether (2x15 mL). Subsequently, toluene is recrystallized (approx. 200 mL), washed with toluene and dried in a drying oven at 140 °C
dried to mass constancy.
Yield (2,3-dibenzoyl-L-tartaric anhydride): 20.0 g (88% d.Th.)
Yield (2,3-dibenzoyl-D-tartaric anhydride): 17.4 g (76% d.Th.)
2,3-Dibenzoyl tartaric acid:
2,3-dibenzoyl tartaric anhydride is suspended in a 500 mL flask in a mixture of 100 mL acetone and 50 mL water and heated to a boil for one hour. The acetone is distilled and the resulting emulsion is filled with water to 400 mL. It is heated to a boil for 15 min and the mixture is cooled to room temperature, stirring vigorously, precipitating a white solid. It is filtered, washed with water and dried in the desiccator over calcium chloride.
((−)-2,3-dibenzoyl-L-tartaric acid):
((+)-2,3-dibenzoyl-D-tartaric acid):