Racemic Resolution of Praziquantel and Praziquanamine

 

START: 13/02/14
FINISH: 14/02/14

Scheme

Hazard and Risk Assessment


Procedure
Dissolved MNR10-2 (6.14 g, 13.4 mmol, 1 equiv.) in toluene (500 mL). Started heating to reflux. At about 70 °C methanesulfonic acid (1.40 mL, 21.4 mmol, 1.6 equiv.). Heated to reflux; oil bath at about ~130 °C. Allowed to cool 40 min later. TLC (75% EtOAc/hexanes) indicated complete consumption of SM (KMnO4 stain) No apparent enamide present.
Reaction allowed to cool. Worked up according to MNR10.

Crude yield: 5.4 g.

Purified using column chromatography: 50 to 70 to 100% ethyl acetate/hexanes. Product obtained as an off-white foam 4.43 g, 90%.

~400 mg was saved. The remainder of the material was taken on to the next step (i.e. KAB119-2)

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