[CH3:1][C:2]1([CH3:10])[CH2:7][CH2:6][CH2:5][C:4]([CH3:9])([CH3:8])[NH:3]1.[Li:11]CCCC.COC1C=CC(C=NC2CCCCC2)=C(C)C=1.CN(OC)C(C1CC1)=O.[Cl-].[NH4+]>O1CCCC1>[Li:11][N:3]1[C:4]([CH3:9])([CH3:8])[CH2:5][CH2:6][CH2:7][C:2]1([CH3:10])[CH3:1]Lithium tetramethylpiperidide was prepared by the treatment of 2,2,6,6-tetramethylpiperidine (1.0 g; 7.0 mmol) in tetrahydrofuran (17 mL) with n-BuLi (1.6 M in hexanes; 8.0 mmol) dropwise at −15° C. After 15 minutes at −15° C., a solution of N-(4-methoxy-2-methylbenzylidene)-cyclohexanamine (660 mg; 2.86 mmol) in tetrahydrofuran (3 mL) was added dropwise to give a purple solution. The reaction mixture was allowed to warm to 0° C. over a 20 minute period, then a solution of N-methyl-N-methoxycyclopropanecarboxamide (630 mg: 4.4 mmol) in tetrahydrofuran (2 mL) was added in one portion while at 0° C. The reaction mixture was kept at room temperature for 30 minutes and then added to saturated aqueous ammonium chloride. The solution was extracted with diethyl ether and the organic phase was washed with brine, dried and concentrated under reduced pressure.
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