In a 2 mL microwave vial, 6-fluoro-5-(7H-pyrrolo[2,3-d]pyrimidin-5-ylmethyl)-pyridin-2-ylamine (68, 9.72 mg, 0.04 mmol) and 3,4,5-trimethoxy-benzaldehyde (69, 15.7 mg, 0.08 mmol) were dissolved in 600 μL of 95:5 ethanol:acetic acid, and silica supported cyanoborohydride (50 mg, 1 mmol/g, 0.05 mmol) was added. The reaction was irradiated for 10 minutes at 160° C. in a microwave. The vial was centrifuged to condense the silica and the supernatant was removed by pipette into another vial. The residual silica was rinsed with 500 μL of ethanol, centrifuged and the supernatant added to the first supernatant. The solvents were removed under vacuum and the resulting material dissolved in dimethyl sulfoxide for purification by HPLC. Samples were purified on Phenomenex C18 column (50 mm×10 mm ID) with mobile phase A of 0.1% trifluoroacetic acid in water, mobile phase B of 0.1% trifluoroacetic acid in acetonitrile, 20-100% B over 16 minutes at a flow rate of 6 mL/min. Appropriate fractions were collected and solvents removed under vacuum to provide the desired compound. MS (ESI) [M+H+]+=424.3.
