反应详情

A round bottomed flask was charged with 3-amino-1-(tert-butoxycarbonyl)azetidine-3-carboxylic acid (prepared according the procedure described in Synthesis 1991, 783-784.) (2.464 mmol), sodium carbonate (1.3 g, 12.32 mmol), a stir bar and water (70 mL). (9H-fluoren-9-yl)methyl carbonochloridate (1.9 g, 7.39 mmol) in 1,4-dioxane (50 mL) was added and the milky solution was stirred overnight at rt. The next day the reaction was poured into a separatory funnel and the aqueous solution washed with diethyl ether (repeated twice) (organic phases were discarded at this stage). The aqueous phase was acidified to pH 2-3 with 1 M HCl (a precipitate was formed) and the product was extracted with EtOAc (repeated 3 times). The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated to dryness. The solid was used without purification in the next step. LRMS (M+Na)+: 461 m/z.

1. customprepared
2. customdescribed in Synthesis 1991, 783-784
3. additionThe next day the reaction was poured into a separatory funnel
4. washthe aqueous solution washed with diethyl ether (
5. customwas formed) and the product
6. extractionwas extracted with EtOAc (repeated 3 times)
7. washThe combined organic layers were washed with brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated to dryness
11. customThe solid was used without purification in the next step