Methyl iodide → tert-Butyl (1-methylcyclopropane-1-sulfonyl)carbamate

Temperature

-78 °C

A solution of tert-butyl cyclopropylsulfonylcarbamate (4.3 g, 20 mmol) was dissolved in dry THF (100 ml) and cooled to −78° C. To this solution was added n-BuLi (17.6 ml, 44 mmol, 2.5 M in hexane) slowly. The reaction mixture was allowed to warm to room temperature over a period of 1.5 h. This mixture was then cooled to −78° C., and a solution of n-BuLi (20 mmol, 8 ml, 2.5M in hexane) was added, stirred for 1 h and a neat solution of methyl iodide (5.68 g, 40 mmol) was added. The reaction mixture was allowed to warm to room temperature for overnight, quenched with aqueous saturated NH4Cl (100 ml) at room temperature. It was extracted with EtOAc (100 ml). The combined organic layer was washed with brine dried on Na2SO4, filtered and evaporated under reduced pressure to give a yellow oil which was crystallized from hexane to afford the product as a slightly yellow solid. (3.1 g, 81%). 1H NMR (400 MHz, DMSO-d6): δ ppm 10.97 (s, 1H), 1.44 (s, 12H), 1.35-1.33 (m, 2H), 0.93-0.91 (m, 2H).

1. temperatureto warm to room temperature over a period of 1.5 h
2. temperatureThis mixture was then cooled to −78° C.
3. temperatureto warm to room temperature for overnight
4. customquenched with aqueous saturated NH4Cl (100 ml) at room temperature
5. extractionIt was extracted with EtOAc (100 ml)
6. washThe combined organic layer was washed with brine
7. customdried on Na2SO4
8. filtrationfiltered
9. customevaporated under reduced pressure
10. customto give a yellow oil which
11. customwas crystallized from hexane
12. customto afford the product as a slightly yellow solid

ORD record

ord-d88d5b3589db4980b74cfa9374dafd97

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08957203B2