Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1) → tert-butyl N-methyl-N-(4-oxocyclohexyl)carbamate

Participants

Reaction Steps

To a solution of (3,3-dimethyl-1,5-dioxa-spiro[5,5]undec-9-yl)-methyl-carbamic acid tert-butyl ester (1.27 g, 3.63 mmol, 1.0 eq.) in acetone (40 mL) and water (20 mL) was added PPTS (228 mg, 0.25 eq.) and the resulting reaction was heated to reflux overnight, cooled to room temperature, concentrated to 20 mL, poured in saturated NaHCO3 and extracted with 3×EtOAc. The combined organic layers were dried over Na2SO4, filtered and concentrated. The residue was purified by silica gel chromatography (hexanes to 20% EtOAc/hexanes) to give methyl-(4-oxo-cyclohexyl)-carbamic acid tert-butyl ester (735 mg, 88%) as a white solid.

Provenance & Evidence