Promethazine → promethazine dibenzoyl-D-tartrate

Participants

Reaction Steps

To prepare promethazine-D-tartrate, promethazine (10 g, 0.035 mol) dissolved in 80 ml acetone was heated in a 60° C. bath while dibenzoyl-D-tartaric acid (12.789 g, 0.036 mol) was added. The resulting clear yellow solution was left at ambient temperature for 3 days (step 2). A heavy precipitate formed, which was filtered off and recrystalized from ethanol four times to give 4.0 g promethazine dibenzoyl-D-tartrate white crystals (step 3).

Provenance & Evidence