Réaction #1552067

Équation de réaction

n-BuLi

H2SO4

Cyclohexanone

2-bromo-N-methyl-N-phenylaniline

→

desired compound

Rendement 30.0%

10-methyl-10H-spiro[acridine-9,1′-cyclohexane]

Rendement 30.0%

Solvants

THF

Conditions de réaction

Traitement

1. 1
   Températureto warm to room temperature
2. 2
   workup.STIRRINGstirred overnight under argon
3. 3
   AutreAfter quenching with saturated ammonium chloride
4. 4
   Extractionthe reaction was extracted with Et2O
5. 5
   Lavagewashed with brine and water
6. 6
   Séchagedried over anhydrous MgSO4
7. 7
   Autrethe solvent evaporated under reduced pressure
8. 8
   AutreTo the neat residue thus obtained
9. 9
   workup.STIRRINGthe mixture stirred at room temperature for 1 h under argon
10. 10
    ExtractionAfter dilution with 30 mL DI H2O, the reaction was extracted with Et2O (5×50 mL)
11. 11
    Lavagewashed with brine and water
12. 12
    Séchagedried over anhydrous MgSO4
13. 13
    Autrethe solvent was evaporated under reduced pressure
14. 14
    AutreThe residue was purified by flash column chromatography

Mode opératoire

A flame-dried two-necked flask was charged with 2-bromo-N-methyl-N-phenylaniline (1.0 g, 3.8 mmol) and 100 mL dry THF under argon and cooled to −78° C. in a dry ice-acetone bath. 2.6 mL of a 1.6 M solution of n-BuLi in hexanes (4.16 mmol) was added dropwise over 5 minutes and the reaction stirred at −78° C. under argon for 1 h. Cyclohexanone (0.43 mL, 0.412 g, 4.2 mmol) was added in one portion to the reaction mixture at −78° C., the reaction allowed to warm to room temperature and stirred overnight under argon. After quenching with saturated ammonium chloride, the reaction was extracted with Et2O, the organic layers combined, washed with brine and water and dried over anhydrous MgSO4 and the solvent evaporated under reduced pressure. To the neat residue thus obtained was added 2 mL of concentrated H2SO4 under argon and the mixture stirred at room temperature for 1 h under argon. After dilution with 30 mL DI H2O, the reaction was extracted with Et2O (5×50 mL), the organic layers were combined, washed with brine and water and dried over anhydrous MgSO4, and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography using hexanes as the eluent to yield 0.3 g (30%) of the desired compound as a clear oil. 1H NMR (400 MHz, CHCl3) δ 1.53 (m, 4H), 2.10 (m, 4H), 3.12 (s, 3H), 5.65 (m, 1H), 6.66 (m, 3H), 7.18 (m, 6H). 13C NMR (100 MHz, CHCl3) δ 22.0, 23.0, 25.6, 28.2, 39.2, 113.7, 116.9, 125.6, 126.3, 127.7, 128.2, 128.5, 130.3, 137.9, 142.8, 145.6, 149.0. HRMS (ESI) calc for C19H21N [M+H]+ 264.1747, found 264.1758. IR (KBr plate) 693 (m), 747(m), 1069 (s), 1155 (m), 1263 (m), 1345 (m), 1499 (s), 1602(s), 2853 (m), 2921 (s) cm−1.

Source