N-bromobutanimide → 8-Bromo-2-butoxy-9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-amine

Participants

Reaction Conditions

Reaction Steps

2-(Butoxy)-9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-amine (for example, as prepared for Intermediate 4) (9.45 g) was dissolved in chloroform (50 mL) and cooled to 0° C. (ice-bath). To this solution was added portion wise N-bromosuccinimide (commercially available, for example, from Aldrich) (6.07 g) keeping the temperature below 3° C. This gave a dark green solution, stirred at 2.5° C. for 30 minutes before allowing to warm to room temperature and then stirring for 6 hours. The reaction mixture was then washed with water (100 mL, twice). The organic phase was dried/separated using a hydrophobic frit and evaporated to give a dark brown gum which was purified by silica chromatography (120 g) (ISCO) using a gradient elution of 0-50% ethyl acetate: cyclohexane to afford the title compound as a pale yellow solid (8.37 g).

Provenance & Evidence