To a oven-dried 10 mL round bottom flask was transferred under Ar 2.88 mL Rieke Zinc (0.14 g Zn, 2.2 mmol, 5 g/100 mL THF) using a 12 gauge needle. Then isopropyl iodide (200 □L, 2 mmol) was added via syringe. The solution turned warm and the content was stirred at rt for 3 h. In a separate flask (25 mL) was dissolved N-(4-(dipropylphosphoryl)phenyl)-2-iodo-9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-amine (0.28 g, 0.5 mmol) and PdCl2(PPh3)2 (0.035 g, 0.05 mmol) in 4.0 mL dry DMF. The Zinc reagent was transferred to the reaction via a syringe. The reaction mixture was stirred at rt overnight. 20 mL EtOAc/20 mL water was added to the reaction mixture and the content was filtered through Celite, washed with 1% MeOH/EtOAc (30 mL). The organic layer was separated and washed with water, brine, and dried Na2SO4. The final product was purified on silica gel (4˜7.5% MeOH/DCM).
