A solution of 2,4,6-trichloropyrimidine-5-carbaldehyde (26.82 mmol) in CH2Cl2 (225 mL) is cooled to −78° C. To this is added a suspension of 1-benzyl-4-hydrazinylpiperidine hydrochloride (26.82 mmol) in Et3N (160.9 mmol), CH2Cl2 (25 mL), and ethanol (15 mL). The solution is allowed to stir at this temperature for 5 minutes, then warmed to room temperature and stirred for an additional 30 minutes, then concentrated in vacuo at 30° C. This dichloride intermediate is dissolved in ethanol (225 mL) and a solution of 8-oxa-3-azabicyclo[3.2.1]octane hydrochloride (24.14 mmol) in Et3N (160.9 mmol) and ethanol (20 mL) is added. The mixture is stirred at room temperature for 1 hour, concentrated, and purified by column chromatography (0-4% methanol in CH2Cl2) provides 3-(1-(1-benzylpiperidin-4-yl)-6-chloro-1H-pyrazolo[3,4-d]pyrimidin-4-yl)-8-oxa-3-azabicyclo[3.2.1]octane. (66%, MS=439.3 (M+H))
