Dimethylformamide → 4-{[t-Butyl(dimethyl)silyl]oxy}-4,5,6,7-tetrahydro-1-benzofuran-2-carboxaldehyde

Temperature

0 °C

To a solution of t-butyl(dimethyl)(4,5,6,7-tetrahydro-1-benzofuran-4-yloxy)silane (4.1 g, 16 mmol) that was obtained in Example 7 (7a) in tetrahydrofuran (30 ml) was slowly added dropwise n-butyllithium (a 1.6 M solution in hexane, 31 ml, 49 mmol) at −78° C. with stirring, and after raising the reaction temperature to 0° C., the resulting mixture was stirred for 30 minutes. After cooling again the reaction mixture to −78° C. while stirring, N,N-dimethylformamide (13 ml, 162 mmol) was added to the reaction mixture with stirring, and the resulting mixture was stirred for 30 minutes. After stirring, a saturated aqueous solution of ammonium chloride (10 ml) was added to the reaction mixture to quench the reaction, and the resulting mixture was poured into water (50 ml) and extracted with ether. The extract was washed with a saturated aqueous solution of sodium chloride and dried over magnesium sulfate. After filtration, the filtrate was evaporated in vacuo, and the crude product of the title compound thus obtained was purified by chromatography on a silica gel column using a mixed solvent of ethyl acetate and hexane (1:9) as the eluent to afford the title compound (4.3 g) in a yield of 94% as a white crystalline solid.

1. stirringthe resulting mixture was stirred for 30 minutes
2. temperatureAfter cooling again the reaction mixture to −78° C.
3. stirringwhile stirring
4. stirringwith stirring
5. stirringthe resulting mixture was stirred for 30 minutes
6. stirringAfter stirring
7. customto quench
8. customthe reaction
9. extractionextracted with ether
10. washThe extract was washed with a saturated aqueous solution of sodium chloride
11. dry with materialdried over magnesium sulfate
12. filtrationAfter filtration
13. customthe filtrate was evaporated in vacuo

ORD record

ord-af4d2eab1d254eaab1a0d1bff962c361

Source dataset

uspto-grants-2010_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07687491B2