Ammonia → 1-Carbamoyl-3-(trimethylstannyl)dibenzofuran

To a stirred solution of the stannane 306 (1.1 g, 2.96 mmol) in anhydrous acetonitrile (5 mL) and THF (15 mL) under a nitrogen atmosphere was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.13 g, 5.9 mmol) and 1-hydroxybenzotriazole hydrate (1.2 g, 8.9 mmol). The solution was stirred 30 min., then 11 mL of a 2.6 M ethanolic ammonia solution was added. The resulting milky white solution was stirred an additional 30 min. before being quenched with saturated aqueous ammonium chloride. The solvents were removed under vacuum and the residue taken up in ether (75 mL) and EtOAc (75 mL). The solution was washed with water (3 times) and brine (2 times), then dried with magnesium sulfate and filtered. The solution was concentrated under vacuum and the residue was purified by flash chromatography (silica gel, 35% EtOAc in hexanes) to provide 979 mg (88% yield) of stannane 307 as a white solid.

1. stirringThe resulting milky white solution was stirred an additional 30 min.
2. custombefore being quenched with saturated aqueous ammonium chloride
3. customThe solvents were removed under vacuum
4. washThe solution was washed with water (3 times) and brine (2 times)
5. dry with materialdried with magnesium sulfate
6. filtrationfiltered
7. concentrationThe solution was concentrated under vacuum
8. customthe residue was purified by flash chromatography (silica gel, 35% EtOAc in hexanes)

ORD record

ord-1544d2a324d44ec9a61177a7642b0e36

Source dataset

uspto-grants-1991_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05025008