3-[(3-Chloro-phenyl)-(2-methyl-propane-2-sulfinylimino)-methyl]-pyrazole-1-sulfonic acid dimethylamide → 3-[1-(3-Chloro-phenyl)-1-(2-methyl-propane-2-sulfinylamino)-ethyl]-pyrazole-1-sulfonic acid dimethylamide

Participants

Reaction Conditions

Reaction Steps

Methylmagnesium bromide (15.08 mL, 21.11 mmol) was added to a solution of 3-[(3-chloro-phenyl)-(2-methyl-propane-2-sulfinylimino)-methyl]-pyrazole-1-sulfonic acid dimethylamide (2.2 g, 5.28 mmol) in THF (25 mL) at 0° C. under nitrogen. The mixture was stirred at 0° C. for 2 hours, quenched with NH4Cl (aq. sat. solution) and the product was extracted with DCM. The organic layer was separated, dried (MgSO4), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica gel; AcOEt in DCM 0/100 to 100/0). The desired fractions were collected and concentrated in vacuo to yield 3-[1-(3-chloro-phenyl)-1-(2-methyl-propane-2-sulfinylamino)-ethyl]-pyrazole-1-sulfonic acid dimethylamide (2.28 g, 99% yield) as a colourless oil which solidified upon standing.

Provenance & Evidence