反应详情

KNO3 (69.97 mg, 0.69 mmol) was added portion-wise to a suspension of 1,2,3,4-tetrahydroquinolin-4-spiro-4′-piperidine (133 mg, 0.66 mmol) in 98% H2SO4 (2 mL) at 0° C. After the addition was complete, the reaction mixture was allowed to warm to room temperature and stirred for additional 2 h. The mixture was then poured into cracked ice and basified with 10% NaOH to pH 8. Boc2O (172 mg, 0.79 mmol) was added dropwise and the mixture was stirred at room temperature for 1 h. The mixture was then extracted with EtOAc and the combined organic layers were dried over Na2SO4, filtered and concentrated to yield crude 7′-nitro-spiro[piperidine-4,4′(1′H)-quinoline], 2′,3′-dihydro-carboxylic acid tert-butyl ester (230 mg), which was used in the next step without further purification.

1. additionAfter the addition
2. stirringthe mixture was stirred at room temperature for 1 h
3. extractionThe mixture was then extracted with EtOAc
4. dry with materialthe combined organic layers were dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated