反应详情

温度

-23 °C

The carboxylic acid of step 7 above (3.71 mmoles) is dissolved in CHCl3 (10 ml), combined with Et3N (3.71 mmoles), cooled to -23° C. and mixed with ethyl chloroformate (3.71 mmoles) for 30 minutes. Aminoquinuclidine (14.8 mmoles) and aqueous K2CO3 (1 ml) are added and the reaction mixture is stirred for 1 hour and diluted with H2O (10 ml). The organic layer is separated, washed with aqueous NaHCO3 (50 ml, sat'd) and H2O (3×50 ml), dried, evaporated and chromatographed with Ether:MeOH (5 g, 1:1) to give a brown oil which is dissolved in EtOH. Concentrated HCl is added to the solution precipitating a white solid which is filtered and recrystallized affording a white solid which NMR indicates is the desired product.

1. customThe organic layer is separated
2. washwashed with aqueous NaHCO3 (50 ml, sat'd) and H2O (3×50 ml)
3. customdried
4. customevaporated
5. customchromatographed with Ether
6. customMeOH (5 g, 1:1) to give a brown oil which
7. customprecipitating a white solid which
8. filtrationis filtered
9. customrecrystallized
10. customaffording a white solid which NMR