反应详情

Under an argon atmosphere oxalyl chloride (1.17 mL, 13.8 mmol) was dissolved in DCM (30 mL) and cooled to −70 C. DMSO (1.95 mL, 27.6 mmol) in DCM (2.5 mL) was added over 5 min and stirred for 10 min. (1-Hydroxymethyl-cyclopropylmethyl)-carbamic acid tert-butyl ester (2.6 g, 12 mmol) in DCM (8.5 mL) was added at −70 C over 5 min and the mixture was stirred for 30 min. Et3N (6.4 mL, 45.6 mmol) was added over 5 min and the temperature was allowed to reach RT over 1 h. H2O was added and the aqueous phase was extracted with DCM (×2). The combined organic phases were washed with brine, dried over Na2SO4, filtered and concentrated in vacuo. The crude product was purified by flash chromatography on silica using heptane:EtOAc 1:15 as eluent to afford (1-Formyl-cyclopropylmethyl)-carbamic acid tert-butyl ester (0.65 g) as an oil.

1. temperaturecooled to −70 C
2. additionwas added at −70 C over 5 min
3. waitto reach RT over 1 h
4. extractionthe aqueous phase was extracted with DCM (×2)
5. washThe combined organic phases were washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude product was purified by flash chromatography on silica