反应详情

Indole-3-carboxylic acid (6.43 gr, 39.9 mmol) is added in portions to a solution of 5.33 mL (37.7 mmol) of trifluoroacetic anhydride in dichloromethane (172 mL) and under nitrogen atmosphere. The resulting suspension is left under stirring for 30 minutes. 7-hydroxy-9-methoxycarbonylmethyl-9-aza-bicyclo[3.3.1]nonan-3-carboxylic acid methyl ester (6 gr, 22.1 mmol) dissolved in dichloromethane (15 mL) is then added dropwise. Next, a catalytic amount of DMAP is added, and the suspension is then left under stirring for 4 h. Following that time, and once the limiting starting product has been used up as shown by thin-layer chromatography (dichloromethane/methanol/ammonia 90:10:1, which reveals potassium permanganate), water (50 mL) is added to the reaction mixture and the mixture is basified with a saturated aqueous solution of sodium bicarbonate. Following filtration to remove the remains of indole-3-carboxylic acid in excess, the resulting phases are separated. The organic phase is dried over magnesium sulphate and evaporated to dryness, to give 7-(1H-Indole-3-carbonyloxy)-9-methoxycarbonylmethyl-9-aza-bicyclo[3.3.1]nonane-3-carboxylic acid methyl ester as a white solid (8.20 gr, 89%) that can be used directly in the following synthesis step.

1. waitThe resulting suspension is left
2. additionis then added dropwise
3. waitthe suspension is then left
4. stirringunder stirring for 4 h
5. additionis added to the reaction mixture
6. filtrationfiltration
7. customto remove the remains of indole-3-carboxylic acid in excess, the resulting phases
8. customare separated
9. dry with materialThe organic phase is dried over magnesium sulphate
10. customevaporated to dryness