Dimethylformamide → 2-Chloro-5-nitrobenzo[d]oxazole
Reaktionsgleichung
S[C:2]1[O:3][C:4]2[CH:10]=[CH:9][C:8]([N+:11]([O-:13])=[O:12])=[CH:7][C:5]=2[N:6]=1.CN(C=O)C.S(Cl)([Cl:21])=O>>[Cl:21][C:2]1[O:3][C:4]2[CH:10]=[CH:9][C:8]([N+:11]([O-:13])=[O:12])=[CH:7][C:5]=2[N:6]=1Komponenten
4
Reaktionsbedingungen
- Temperatur
- 65 °C
Versuchsvorschrift
Subsequently, the crude 2-mercapto-5-nitrobenzoxazole (10 g, 51 mmol), previously prepared, was dissolved in thionyl chloride (100 mL). DMF (60 μL) was added and the reaction mixture was heated at 65° C. for 45 min. After cooling, the solvent was removed under reduced pressure and to the residue, toluene was added twice (2×20 mL) and each time subsequently evaporated in vacuo to remove volatiles via azeotrope. The resultant crude product was dissolved in ethyl acetate (400 mL), washed with brine (200 mL), dried over Na2SO4, filtered, and concentrated to give compound 29, 2-chloro-5-nitrobenzoxazole, as (8.2 g, crude).