1-Methyl-4-piperidone → 1-methyl-4-(2-trityl-2,3-dihydro-1H-isoindol-5-yl)-piperidin-4-ol

HRID 2412234Notes

Reaction equation

HRID 2412234 reaction equation
Br[C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[CH2:7][N:6]([C:11]([C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1)([C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)[CH2:5]2.C([Li])CCC.[CH3:35][N:36]1[CH2:41][CH2:40][C:39](=[O:42])[CH2:38][CH2:37]1>C1COCC1>[CH3:35][N:36]1[CH2:41][CH2:40][C:39]([C:2]2[CH:3]=[C:4]3[C:8](=[CH:9][CH:10]=2)[CH2:7][N:6]([C:11]([C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)([C:18]2[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=2)[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH2:5]3)([OH:42])[CH2:38][CH2:37]1

Participants

5

Reactant 3

HCID 740491-Methyl-4-piperidoneHCID 592631135-Bromo-2-trityl-isoindolineHCID 178418339Butyllithium

Product 1

HCID 592631371-methyl-4-(2-trityl-2,3-dihydro-1H-isoindol-5-yl)-piperidin-4-olYield 57%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Under nitrogen, a solution of 5-bromo-2-trityl-2,3-dihydro-1H-isoindole (2.03 g, 4.6 mmol) in THF (20 mL) was cooled to −78° C. n-Butyllithium solution (2.5M in hexanes, 2.0 mL, 5 mmol) was added over 5 minutes, then after 10 minutes, 1-methyl-4-piperidone was added dropwise. After a further hour, the cooling bath was removed and the reaction quenched with sodium bicarbonate solution. The mixture was extracted with ethyl acetate then the organic phase washed with brine, dried (MgSO4) and concentrated. The residue was purified by flash chromatography on silica (gradient elution with 2M methanolic ammonia/dichloromethane, 0% to 5%) to afford 1-methyl-4-(2-trityl-2,3-dihydro-1H-isoindol-5-yl)-piperidin-4-ol as a pink foam (1.25 g, 57%). 1H NMR (MeOH-d4) 7.56 (6H, dd), 7.28 (6H, t), 7.25-7.21 (2H, m), 7.15 (3H, t), 7.03 (1H, d), 3.92 (2H, s), 3.91 (2H, s), 2.70 (2H, d), 2.53 (2H, td), 2.33 (3H, s), 2.06 (2H, td), 1.70 (2H, d). MS: [M+H]+ 475.

Workup

  1. additionwas added over 5 minutes
  2. waitAfter a further hour
  3. customthe cooling bath was removed
  4. customthe reaction quenched with sodium bicarbonate solution
  5. extractionThe mixture was extracted with ethyl acetate
  6. washthe organic phase washed with brine
  7. dry with materialdried (MgSO4)
  8. concentrationconcentrated
  9. customThe residue was purified by flash chromatography on silica (gradient elution with 2M methanolic ammonia/dichloromethane, 0% to 5%)

Sources & evidence

ORD record
ord-28ae3ae4ea584d959596f2403e3183ef
Source dataset
uspto-grants-2014_08
Patent number
US08816087B2

Reaction notes

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