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 with stirring overnight; then was quenched with aqueous saturated NH4Cl (100 ml) at room temperature. The mixture was extracted with EtOAc (100 ml). The organic layer was washed with brine; dried over Na2SO4, filtered and concentrated 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
4. stirringwith stirring overnight
5. customthen was quenched with aqueous saturated NH4Cl (100 ml) at room temperature
6. extractionThe mixture was extracted with EtOAc (100 ml)
7. washThe organic layer was washed with brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure
11. customto give a yellow oil which
12. customwas crystallized from hexane

ORD record

ord-2dba0ba9f8aa418d871bd5132dadab8b

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09409943B2