2-Chlorobenzoxazole

clear yellow liquid

To a suspension of 1 (10 mmol, 1.51 g) in SOClSpecifically include:Solid phosgene (BTC) is selected as the chlorinating agent.2 mmol of 2-mercaptobenzoxazole prepared in the step 1 was added to the flask.Add 10 mL of toluene or cyclohexane as solvent to the flask.4 mmol of solid triphosgene was added to the flask.Warm up to 50 ° C under magnetic stirring, keep warm for 10 min, and then slowly heat up.Each temperature is raised at 10 ° C for 10 min, when the temperature is raised to 105 ° C, the temperature is kept for 1 h; TCL point plate analysis, Properly extend the reaction time, After separation by column chromatography, 0.142 g of 2-chlorobenzoxazole was obtained.The product was slightly yellowish liquid with a yield of 46percent.General procedure: The substituted 2-aminophenol (1eq.) in water and 95percent ethanol was added potassium carbonate (1eq.) and CSBenzoxazole (1 mmol, 119.1 mg), Carbon tetrachloride (1.1 mmol, 169.2 mg) was placed in a 10 mL round bottom flask.Added 5 mL of N, N-dimethylformamide and sodium tert-butoxide (4.0 mmol, 384.4 mg).Stir at room temperature for 3 hours, TLC monitored the endpoint of the reaction.The mixture was poured into water and extracted with dichloromethane. The organic phase was collected and dried. The dichloromethane was removed by rotary evaporation to give the crude product.The crude product was subjected to silica gel column chromatography with petroleum ether and ethyl acetate as eluent (volume ratio = 30:1).2-Chlorobenzoxazole (light yellow oily liquid, 136.7 mg, yield 89percent) was obtained.To a suspension of 1.5 g (10 mmol) of product 3 in 8.6 mL (90 mmol) of POCl3at room temperature was added 2.5 g (12 mmol) of PCl5 along with 7 mL of CH2Cl2.The reaction mixture turned into a solution after the addition. After 12h of stirring at3room temperature, the reaction mixture was concentrated to remove excess POCl3, and the residue was treated with saturated aqueous NaHCO3 solution until pH 8 wasreached. The aqueous phase was extracted with CH2Cl2, and the combined CH2Cl2extracts were washed with brine, dried over MgSO4, and then concentrated to give 1.1g of crude product 4. Short-column chromatography on silica gel with petroleumether/ethyl acetate (200: 3) provided 864 mg (60percent yields) of product 4 as thecolorless oil.

Molecular Weight:153.56
XLogP3:2.8
Hydrogen Bond Acceptor Count:2
Exact Mass:152.9981414
Monoisotopic Mass:152.9981414
Topological Polar Surface Area:26
Heavy Atom Count:10
Complexity:131
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes