Orotic Acid → 2,6-Dioxo-1,2,3,6-tetrahydropyrimidine-4-carbonyl bromide

Participants

Reaction Conditions

Reaction Steps

In a dry 2-necked, round bottomed flask, equipped with a magnetic stirrer and fixed with a separatory funnel, containing 10.07 mL (130 mmol) of thionyl bromide, and a water condenser, is placed 15.61 g (100 mmol) of orotic acid. Addition of the thionyl bromide is completed with heating to about 45° C. over the course of about 80 minutes. When addition of the thionyl bromide is complete the mixture is heated and stirred for an additional hour. The water condenser is then replaced with a distillation side arm condenser and the crude mixture is distilled. The crude distillate in the receiving flask is then fractionally distilled to obtain the acyl bromide, 2,6-dioxo-1,2,3,6-tetrahydropyrimidine-4-carbonyl bromide (orotoyl bromide). This acyl bromide, 6.57 g (30 mmol), is put into a dry separatory funnel and combined with 25 mL of dry DCM for use in the next step of the reaction.

Provenance & Evidence