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

Temperature

0 °C

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

1. customTo an oven dried 250 mL round bottomed flask
2. additionA magnetic stirbar was added
3. additionadded to the flask dropwise via syringe
4. customwas fitted to the flask
5. temperatureheated
6. temperatureto reflux for 16 h
7. temperatureThe reaction mixture was cooled to room temperature
8. customtransferred to a separatory funnel
9. washThe organic phase was washed with saturated NaHCO3 solution (2×70 mL), H2O (2×70 mL), and Brine (1×70 mL)
10. dry with materialDried over Na2SO4
11. filtrationfiltered
12. concentrationconcentrated under reduced pressure
13. customThe crude mixture was purified by flash chromatography
14. washeluting with 20%→30% acetone in hexanes

ORD record

ord-a626677dec3743dd9483c7491d58127a

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08263774B2