Ethanolamine → Dihydrothebaine

Participants

Reaction Conditions

Reaction Steps

Thebaine (4.0 g dry basis, 12.9 mmol) is placed in a mixture of 1-methoxy-2-propanol (13.0 g) and ethanolamine (1.3 g, 21.3 mmol, 1.65 equiv) and is heated to 110° C. In anther vessel, p-toluenesulfonylhydrazide (4.8 g, 25.8 mmol, 2.0 equiv) is dissolved at room temperature in a mixture of ethanolamine (9.6 g, 157.2 mol, 12.2 equiv) and 1-methoxy-2-propanol (0.8 g) and the solution is added in portions to the thebaine mixture over about a 2 hour period while maintaining the batch temperature at ˜110° C. The reaction mixture is held at 110 to 112° C. for 1 hour then cooled to 22° C. and water (24 g) added while maintaining the batch temperature at ≦30° C. The resulting slurry (pH 10.8) is filtered and the product is washed with water (3×8 g) and dried at 40° C. to constant weight to give 8,14-dihydrothebaine (3.63 g, 90.1% yield; 98.8 area % purity by HPLC).

Provenance & Evidence