反应详情

A solution of bis(2,2,2-trifluoroethyl)(methoxycarbonylmethyl)phosphonate (0.648 g, 2.04 mmol, 1.2 eq) and 18 crown 6 (2.24 g, 8.5 mmol, 5.0 eq) in tetrahydrofuran (30 mL), was cooled to n78° C. To this at n78° C. was added potassium bis(trimethylsilyl)amide (4.08 mL, 2.04 mmol, 1.2 eq). The reaction mixture was stirred at n78° C. for 30 min and treated with a solution of 2-imidazole-4-ylcyclopropanecarbaldehyde (0.64 g, 1.7 mmol) in tetrahydrofuran (5 mL). The reaction mixture was again stirred at n78° C. for 1 hour, treated with aqueous satd. ammonium chloride solution and extracted with ether. The organic layer was separated, washed with water and dried over anhyd. Na2SO4. Crude product was purified by flash column eluted with ethyl acetate: hexane (1:3) to give trityl protected product (0.730 g). A small amount (150 mg) of this product was deprotected by treatment with 2 N HCl at 90° C. for 1 h to give final product (yield=62 mg).

1. stirringThe reaction mixture was again stirred at n78° C
2. waitfor 1 hour
3. additiontreated with aqueous satd
4. extractionammonium chloride solution and extracted with ether
5. customThe organic layer was separated
6. washwashed with water
7. customdried over anhyd
8. customCrude product was purified by flash column
9. washeluted with ethyl acetate: hexane (1:3)
10. customto give trityl protected product (0.730 g)