Hydrochloric Acid → Uracel, 3-ethyl-

Participants

Reaction Steps

13.47 g (40 mM) of 6-amino-1-(4-chlorobenzyl)-5-isobutyrylaminouracil were dissolved in 130 ml of DMF, treated at 5° C. with 4.57 g (40.8 mM) potassium t-butoxide and after dissolution, 3.28 ml (44 mM) of ethyl bromide added. After 3 hours, another 1.14 g of t-BuOK and 1.64 ml of ethyl bromide were added. After a further 1.5 hours, 1.64 ml of ethyl bromide was supplemented. After a total of 22 hours, the solution was neutralized with 1N HCl to pH 7 and the solvents evaporated in vacuo. The residue was taken up in dichloromethane-water and the organic phase collected giving 17.66 of crude 3-ethyl uracil, which was dissolved in 17.6 ml of 1N NaOH and heated under reflux for 1 hour. The solution was treated twice with 1 g of charcoal, filtered and neutralized with 5N HCl to pH 7. The solid was diluted with water, collected, and dried. The crude material was recrystallized from methanol to give 7.42 g (49.2%) of 3-(4-chlorobenzyl)-1-ethyl-8-isopropyl-xanthine, mp 221-2° C.

Provenance & Evidence