Methyl iodide → Carbamic acid, [(1-methylcyclopropyl)sulfonyl]-, 1,1-dimethylethyl ester

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence