4-Toluenesulfonyl chloride → 2-(4,4-Dimethyl-4,5-dihydro-1,3-oxazol-2-yl)quinoline

Participants

Reaction Conditions

Reaction Steps

To an oven dried 250 mL round bottomed flask was weighed p-Toluene sulfonyl chloride (1.049 g, 5.5 mmol) and N,N-dimethylaminopyridine (39.1 mg, 0.32 mmol). A magnetic stirbar was added and the flask was placed under N2 atmosphere. The flask was charged with DCE (20 mL) and triethylamine (3.2 mL, 23 mmol). The N-(1-hydroxy-2-methylpropan-2-yl)quinoline-2-carboxamide (1.112 g, 4.55 mmol) was dissolved in DCE (15 mL) and added to the flask dropwise via syringe. The reaction mixture was stirred at 0° C. for 15 min, before a reflux condenser was fitted to the flask and heated to reflux for 16 h. The reaction mixture was cooled to room temperature, transferred to a separatory funnel and diluted with DCM (70 mL). The organic phase was washed with saturated NaHCO3 solution (2×70 mL), H2O (2×70 mL), and Brine (1×70 mL). Dried over Na2SO4, filtered and concentrated under reduced pressure. The crude mixture was purified by flash chromatography eluting with 20%→30% acetone in hexanes to afford 4,4-dimethyl-2-(quinoline-2-yl)-oxazoline in 47% yield (484 mg, 2.14 mmol) according to the reaction

Provenance & Evidence