3,4-dihydro-2H-pyran → 2,6-Dichloro-9-(tetrahydro-2H-pyran-2-yl)-9H-purine

Participants

Reaction Conditions

Reaction Steps

2,6-Dichloro-9H-purine (20 g, 0.11 mol) and 4-toluenesulphonic acid monohydrate (0.2 g) were dissolved in ethyl acetate (300 ml), the mixture heated to 50° C. and a solution of 3,4-dihydro-2H-pyran (12.6 ml, 0.14 mol) in ethyl acetate (50 ml) added slowly over 30 minutes. The reaction mixture was cooled to room temperature, water (100 ml) added and the pH of the solution adjusted to 7 by addition of a saturated aqueous solution of sodium hydrogen carbonate. The organic layer was separated, washed sequentially with water and brine, dried over anhydrous magnesium sulphate, filtered and the solvent removed under reduced pressure. The residue was azeotroped with pentane (×2) to afford the title compound as a slightly impure white solid (30.9 g).

Provenance & Evidence