Dimethyl Sulfoxide → tert-butyl 4-oxotetrahydrofuran-3-ylcarbaMate

Temperature

-78 °C

A mixture of oxalyl chloride (3.20 mL, 36.9 mmol) in THF (137 mL) is cooled to −78° C. under nitrogen and treated dropwise with DMSO (5.24 mL, 73.8 mmol). The mixture is stirred for 20 min at −78° C., whereupon trans-tert-butyl N-[4-hydroxytetrahydrofuran-3-yl]carbamate (5.00 g, 24.6 mmol) is added. Stirring at −78° C. is continued for 1 h. Triethylamine (18.5 mL, 133 mmol) is added and the reaction is warmed to room temperature. The reaction is stirred for 16 h, then water (100 mL) is added and the reaction is concentrated in vacuo to remove THF. The mixture is extracted with EtOAc (3×70 mL), the combined organics dried over magnesium sulfate, filtered, and concentrated to give 6.4 g of crude product as an orange oil. The crude product is purified on silica gel (220 g, 15-30% EtOAc/hexanes) to give the title compound as a yellow oil (2.20 g, 44%). GC-MS m/z 201 (M)+, 143 (M-t-Bu)+.

1. additionis added
2. temperaturethe reaction is warmed to room temperature
3. stirringThe reaction is stirred for 16 h
4. concentrationthe reaction is concentrated in vacuo
5. customto remove THF
6. extractionThe mixture is extracted with EtOAc (3×70 mL)
7. dry with materialthe combined organics dried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customto give 6.4 g of crude product as an orange oil
11. customThe crude product is purified on silica gel (220 g, 15-30% EtOAc/hexanes)

ORD record

ord-f6566f26513948fea0a7289b83e288aa

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658693B2