A mixture of 14.6 g of 3-iodo-4-hydroxy-6-pivaloylaminopyrrolo[2,3-d]pyrimidine, 7.6 g of 2-(2-propynyloxy)-tetrahydropyran, 798 mg (10%) of palladium chloride, 2.36 g (20%) of triphenyl phosphine, 428 mg (5%) of cuprous iodide, 45 ml of triethyl amine and 700 ml of acetonitrile is heated at reflux under nitrogen for 12 hours. There then are added to the hot reaction mixture 3.2 g of 2-(2-propynyloxy)-tetrahydropyran and reflux is continued for an additional 12 hours. After heating for a total of 24 hours under reflux, the solvent is removed under reduced pressure, and the residue filtered through silica gel using 2% methanol in methylene chloride. This filtrate is concentrated and chromatographed on silica gel eluting with 20:1 ethyl acetate:hexane mixture to give 3-(3-tetrahydropyr-2-yloxyprop-1-yn-1-yl)-4-hydroxy-6-pivaloylaminopyrrolo[2,3-d]pyrimidine which is further purified by recrystallization with ethyl acetate.
