Reaction #336837

Reaction equation

ammonia

Phosphorus oxychloride

5-chloro-2-cyclopropyl-1,6-dihydro-6-oxo-4-pyrimidinecarboxylic acid

product

5-chloro-2-cyclopropyl-1,6-dihydro-6-oxo-4-pyrimidine-carboxylic acid

→

title compound

5,6-dichloro-2-cyclopropyl-4-pyrimidinecarboxylic acid

Solvents

acetonitrile

Conditions

Workup

1. 1
   TemperatureThe reaction mixture was cooled to 30° C.
2. 2
   Temperaturemaintained at 5-10° C.
3. 3
   Concentrationthe mixture was concentrated at 25° C. with a rotary evaporator
4. 4
   Otherto remove acetonitrile
5. 5
   Otherthe precipitated product was isolated by filtration
6. 6
   Washwashed with water (2×25 mL)
7. 7
   OtherThe solid was dried in a vacuum oven

Procedure

Phosphorus oxychloride (14 mL, 23 g, 0.15 mol) and 5-chloro-2-cyclopropyl-1,6-dihydro-6-oxo-4-pyrimidinecarboxylic acid (i.e. the product of Step B1 or B2) (75 g, 300 mmol) were combined and heated at 85° C. for 3 h. The reaction mixture was cooled to 30° C. and added over 30 minutes to a mixture of acetonitrile (50 mL) and ice water (80 mL), with the temperature maintained at 5-10° C. and the pH maintained in the range 1-3 by co-feeding aqueous ammonia (28%). The pH was adjusted to about 2, the mixture was concentrated at 25° C. with a rotary evaporator to remove acetonitrile, and the precipitated product was isolated by filtration and washed with water (2×25 mL). The solid was dried in a vacuum oven to afford the title compound (ca. 7.0 g).

Source