7-[(3aS,4R,6R,6aR)-6-({[4-(5,6-Dichloro-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-1,3-benzodiazol-2-yl)butyl]amino}methyl)-2,2-dimethyl-hexahydrocyclopenta[d][1,3]dioxol-4-yl]-N-cyclopropyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine (0.222 g, 0.311 mmol) was dissolved in THF (5 ml) and MeOH (5 ml) and formaldehyde (0.05 ml, 0.621 mmol) was added at r.t. under N2. NaBH3CN (0.023 g, 0.373 mmol) was added at r.t. and the reaction left for 2 hrs. After this time LCMS analysis showed the reaction was complete so the reaction was quenched by addition of sat. NaHCO3 solution (10 ml), water (10 ml) and DCM (10 ml). The organic layer was separated and the aqueous layer was extracted with DCM (2×10 ml). The combined organic layers were dried over MgSO4, filtered and concentrated in vacuo to give the crude product. The crude product was purified by silica flash column chromatography using between 100% DCM and 15% MeOH:95% DCM as eluent to give the product as a colorless oil
