Ethanolamine → Dihydrothebaine

Participants

Reaction Conditions

Reaction Steps

Thebaine (4.0 g dry basis, 12.9 mmol) is placed in a mixture of 2-methoxyethanol (13.0 g) and ethanolamine (1.3 g, 21.3 mmol, 1.65 equiv) and is heated at 110 to 114° C. p-Toluenesulfonylhydrazide (4.8 g, 25.8 mmol, 2.0 equiv) is dissolved at 15 to 25° C. in a mixture of ethanolamine (9.6 g, 157.2 mol, 12.2 equiv) and 2-methoxyethanol (0.8 g) and then the solution is added in portions to the thebaine mixture at such a rate that the batch temperature is maintained in the range 110 to 115° C. The reaction mixture is held at 110 to 114° C. for 1 hour then cooled to less than 20° C. after which water (24 g) is added to the mixture. The resulting slurry (pH 10.9) is stirred, further cooled to 0 to 5° C. and then filtered. The product is washed with water (3×8 g) and dried at 40° C. to constant weight to give 8,14-dihydrothebaine (3.84 g, 95.3% yield; 98.4 area % purity by HPLC).

Provenance & Evidence