Yield:54851-35-3 92%

Reaction Conditions:

with sodium hydrogensulfide in methanol;water; for 4 h;Heating / reflux;

Steps:

21.a

To a clear solution of sodium hydrosulfide (2.1 g, 23 mmol) in water (3 mL) was added 5-amino-4,6- dichloropyrimidine (3.5 g, 21 mmol) and methanol (30 mL), and the mixture was re fluxed for 4 h. It was evaporated and to the residue was added EtOAc (30 mL) and saturated aqueous ammonium chloride (50 mL). The organic layer was separated and dried, concentrated and purified by column chromatography (Hexane/EtOAc 3:1) to give 3.2 g (92%) of the title compound.

References:

WO2008/57402,2008,A2 Location in patent:Page/Page column 61