反应详情

A microwave vial was charged with (S)-3-bromo-7-iodo-5′,6′-dihydrospiro[chromeno[2,3-b]pyridine-5,4′-[1,3]oxazin]-2′-amine (500 mg, 1.059 mmol, Intermediate 25), copper(I) iodide (20.17 mg, 0.106 mmol), (+)-sodium 1-ascorbate (10.49 mg, 0.053 mmol) and sodium azide (0.074 ml, 2.118 mmol). The vial was evacuated and backfilled with nitrogen. EtOH (2 ml), rac-trans-1,2-diaminocyclohexane (0.019 ml, 0.159 mmol) and water (0.9 ml) were added. The reaction mixture was heated overnight to 56° C. An additional portion of each reagent were added and the reaction was heated for additional 6 hours. The reaction mixture was partitioned between water and EtOAc. The organic phase was separated and dried over MgSO4. The solvent was removed under reduced pressure and the residue was purified by flash chromatography (silical gel, 20-100% EtOAc/hexanes) to afford (S)-7-azido-3-bromo-5′,6′-dihydrospiro[chromeno[2,3-b]pyridine-5,4′-[1,3]oxazin]-2′-amine as a yellow solid.

1. customThe vial was evacuated
2. temperatureThe reaction mixture was heated overnight to 56° C
3. additionAn additional portion of each reagent were added
4. temperaturethe reaction was heated for additional 6 hours
5. customThe reaction mixture was partitioned between water and EtOAc
6. customThe organic phase was separated
7. dry with materialdried over MgSO4
8. customThe solvent was removed under reduced pressure
9. customthe residue was purified by flash chromatography (silical gel, 20-100% EtOAc/hexanes)