反应详情

A solution of 5-({[t-butyl(dimethyl)silyl]oxy}methyl)-N′-hydroxyfuran-2-carboximidamide (0.19 g, 0.70 mmol) that was obtained in Example 2 (2b), 4-cyclohexylbenzoic acid (0.16 g, 0.77 mmol), and N,N′-dicyclohexylcarbodiimide (0.17 g, 0.84 mmol) in dichloromethane (1.5 ml) was stirred for 1 hour. After stirring, the reaction mixture was diluted with ether, and insoluble materials were removed by filtration with Celite, and then the filtrate was evaporated in vacuo. Subsequently, to a solution of the residue obtained in tetrahydrofuran (1.0 ml) was added tetrabutylammonium fluoride (a 1.0 M solution in tetrahydrofuran, 1.1 ml, 1.1 mmol) with stirring, and the resulting mixture was stirred at 60° C. for 1 hour. After stirring, the reaction mixture was poured into water (20 ml) to quench the reaction 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 (1:1) as the eluent to afford the title compound (0.18 g) in a yield of 81% as a white crystalline solid.

1. stirringAfter stirring
2. customwere removed by filtration with Celite
3. customthe filtrate was evaporated in vacuo
4. customSubsequently, to a solution of the residue obtained in tetrahydrofuran (1.0 ml)
5. stirringwith stirring
6. stirringthe resulting mixture was stirred at 60° C. for 1 hour
7. stirringAfter stirring
8. customto quench
9. customthe reaction
10. extractionextracted with ether
11. washThe extract was washed with a saturated aqueous solution of sodium chloride
12. dry with materialdried over magnesium sulfate
13. filtrationAfter filtration
14. customthe filtrate was evaporated in vacuo