D-Lactic Acid → HCID 13923246, compound

Participants

Reaction Conditions

Reaction Steps

2740 g (1 mole) of purified 3.3% strength by weight aqueous D(-)-lactic acid are initially taken, and 182 g (1 mole) of racemic 3,3,6-trimethyl-9-oxo-1,5-diazabicyclo[4.3.0]nonane are introduced slowly at 22° C. The reaction is slightly exothermic, and the temperature increases to 25° C. Stirring is continued for 1 hour, and the mixture is evaporated down in a rotary evaporator at a maximum bath temperature of 70° C. and under 30 mm Hg. 277 g of residue are obtained in the form of a reddish oil, to which 300 ml of tetrahydrofuran are added while stirring. After about 1 hour, the suspension containing the precipitated colorless crystals is cooled to -5° C. and stirred for half an hour at this temperature, and the product is washed with 3×50 ml of tetrahydrofuran at -20° C. and dried in a drying oven at 50° C.

Provenance & Evidence