Methanesulfonyl chloride → Tert-butyl 3-(methanesulfonyloxy)azetidine-1-carboxylate

To a solution of tert-butyl 3-hydroxy-1-azetanecarboxylate (4.0 g, 0.023 mol) in anhydrous pyridine (50 mL), methanesulfonyl chloride (5.3 g, 0.046 mol) was added at −20° C. under an atmosphere of nitrogen. The yellow heterogeneous mixture was stirred between −20° C. to −30° C. for one hour, then between 0° C. to −5° C. for two hours. The mixture was poured into ice water (50 mL). The water phase was extracted with ethyl acetate (2×50 mL). The combined organic extracts were washed with water (1×50 mL), 5% aquoeus citric acid (4×50 mL), water (1×50 mL), saturated sodium bicarbonate (1×50 mL), and brine (1×50 mL) and dried over sodium sulfate. The solvent was removed under reduced pressure to yield tert-butyl 3-[(methylsulfonyl)oxy]-1-azetanecarboxylate as brownish oil (4.85 g, 0.019 mol).

1. waitbetween 0° C. to −5° C. for two hours
2. extractionThe water phase was extracted with ethyl acetate (2×50 mL)
3. washThe combined organic extracts were washed with water (1×50 mL), 5% aquoeus citric acid (4×50 mL), water (1×50 mL), saturated sodium bicarbonate (1×50 mL), and brine (1×50 mL)
4. dry with materialdried over sodium sulfate
5. customThe solvent was removed under reduced pressure

ORD record

ord-d738ff5f5c5e4259aa32121155ab35d5

Source dataset

uspto-grants-2005_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06921763B2