Hydrochloric Acid → HCID 69422275, compound

Participants

Reaction Conditions

Reaction Steps

Methylamine (2.0M in THF; 10 ml, 20 mmol) was added dropwise over 5 minutes to a solution of 2-cyclopenten-1-one (1.68 ml, 20 mmol) in dichloromethane (16 ml) cooled to −4° C. The resulting mixture was stirred at −4° C. to +1° C. for 1 hour 30 minutes then added to a solution of 3-toluenesulfonyl chloride (3.83 g, 20.1 mmol), triethylamine (2.8 ml, 20 mmol) and 4-dimethylaminopyridine (128.4 mg, 1.05 mmol) in dichloromethane (50 ml). The reaction mixture was stirred at 0° C. for 30 minutes, allowed to warm to room temperature over 30 minutes then stirred for a further 2 hours. The mixture was poured into 1M hydrochloric acid (100 ml), separated and the organic phase washed with saturated aqueous sodium hydrogen carbonate (100 ml). The organic phase was dried (MgSO4), concentrated in vacuo and the residue purified by flash chromatography, eluting with 1:3, 1:2 then 1:1 ethyl acetate-isohexane, to give the title compound (2.48 g, 46%) as an pale amber oil; δH (400 MHz, CDCl3) 1.89 (1H, m), 2.05 (1H, m), 2.10-2.22 (3H, m), 2.34 (1H, m), 2.44 (3H, s), 2.78 (3H, s), 4.60 (1H, m), 7.40 (2H, m), 7.60 (2H, m).

Provenance & Evidence