Boron trifluoride etherate → Diisopropylether ethyl acetate

Participants

Reaction Steps

(5RS, 6SR)-2-[4-(Ethylthio)phenyl]-6-phenyl-5,6-dihydro-4H-1,3-oxazin-5-ol may be prepared in the following manner: working as in Example 38 for the preparation of 2-[4-(dimethylamino)phenyl]-6-phenyl-5,6-dihydro-4H-1,3-oxazin-5-ol, but starting with N-[(2RS, 3RS)-2,3-epoxy-3-phenylpropyl]-4-(ethylthio)benzamide (10 g) and boron trifluoride etherate (4.3 cc) in dichloromethane (100 cc), and after crystallization of the residue obtained in an ethyl acetate/diisopropyl ether mixture (30:70 by volume), (5RS, 6SR)-2-[4-(ethylthio)phenyl]-6-phenyl-5,6-dihydro-4H-1,3-oxazin-5-ol (4.2 g), m.p. 120° C., is obtained.

Provenance & Evidence