tert-Butanol → tert-Butyl (1-methylcyclopropyl)carbamate

Temperature

80 °C

To a solution of 1-methylcyclopropanecarboxylic acid (3.52 g) in tert-butanol (50 mL) were added diphenylphosphoryl azide (7.58 mL) and triethylamine (4.90 mL), and the mixture was stirred at 80° C. for 15 hours. After cooling to room temperature, the reaction mixture was concentrated in vacuo. To the residue were added water and an aqueous saturated sodium hydrogencarbonate solution, and the mixture was extracted with diethylether. The organic layer was dried over magnesium sulfate and filtered. The filtrate was concentrated in vacuo, and the resultant crude product was purified by column chromatography on silica gel (solvent: hexane/ethyl acetate=90/10 to 87/13) to give 1-methyl-1-[N-(tert-butoxycarbonyl)amino]-cyclopropane (4.66 g, yield: 77%) as a colorless solid.

1. temperatureAfter cooling to room temperature
2. concentrationthe reaction mixture was concentrated in vacuo
3. additionTo the residue were added water
4. extractionan aqueous saturated sodium hydrogencarbonate solution, and the mixture was extracted with diethylether
5. dry with materialThe organic layer was dried over magnesium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated in vacuo
8. customthe resultant crude product was purified by column chromatography on silica gel (solvent: hexane/ethyl acetate=90/10 to 87/13)

ORD record

ord-17e248e2cb024dbe886e6b9ec5d9a371

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08921380B2