Dopamine → Dopamine ribonamide

Participants

Reaction Steps

D-(+)-Ribonic acid gamma-lactone (2.0 gm, 13.5 mmol) was added to methanol (25 mL) in a 100 mL round bottom flask with stirring until dissolved, and then an additional 5 min. 3-Hydroxytyramine (2.6 gm, 13.5 mmol) was added slowly, allowing it to dissolve, with stirring, over the course of about 10 minutes. Triethylamine (1.4 gm, 13.5 mmol) was then added and the reaction mixture refluxed for 4 hr. in the dark, during which time the solution acquired a slight yellow color. Solvents were removed by rotary evaporation using anhydrous ethanol as an azeotrope to remove any residual water. The resultant dried product constituted a thick syrup which solidified upon standing (1 hr.) to give a white solid. The white solid product was stirred (1 hr.) with acetone (40 mL), again resulting in a white solid as a product. The resultant solid was collected by filtration and dried in vacuo for 6 hrs. yielding dopamine ribonamide (3.83 gm, 12.7 mmol, 94.1% yield .) 1H and 13C-NMR results and CHN analyses were consistent with structure. Melting point was 90-91° C. Predicted C13H19N1: (301.30): C, 51.82; H, 6.36; N, 4.65; Analysis results of synthesis product: C, 51.67; H, 6.40; N, 4.69.

Provenance & Evidence