Potassium Carbonate → Tert-butyl 3-ethynyl-3-methylpiperidine-1-carboxylate

HRID 2178357Notes

Reaction equation

HRID 2178357 reaction equation
[CH:1]([C:3]1([CH3:16])[CH2:8][CH2:7][CH2:6][N:5]([C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[CH2:4]1)=O.[C:17](=O)([O-])[O-].[K+].[K+].[N+](=C(P(=O)(OC)OC)C(=O)C)=[N-]>CO>[C:1]([C:3]1([CH3:16])[CH2:8][CH2:7][CH2:6][N:5]([C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[CH2:4]1)#[CH:17]

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 222589171,1-Dimethylethyl 3-formyl-3-methyl-1-piperidinecarboxylateHCID 136023029(1E)-1-diazo-1-dimethoxyphosphorylpropan-2-one

Product 1

HCID 118113975Tert-butyl 3-ethynyl-3-methylpiperidine-1-carboxylateYield 73%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a stirred solution of tert-butyl 3-formyl-3-methylpiperidine-1-carboxylate (2.10 g, 9.25 mmol) in methanol (40 mL) was added potassium carbonate (2.76 g, 20.00 mmol). The mixture was treated with dimethyl 1-diazo-2-oxopropylphosphonate (2.11 g, 11.00 mmol), and the resulting mixture was allowed to stir at room temperature. After 2 h, the mixture was concentrated, diluted with water, and extracted with ethyl acetate. The organic phase was washed with brine, dried over magnesium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography (6% ethyl acetate/petroleum ether elute) to afford 1.50 g (73%) of tert-butyl 3-ethynyl-3-methylpiperidine-1-carboxylate as a pale yellow oil.

Workup

  1. concentrationthe mixture was concentrated
  2. additiondiluted with water
  3. extractionextracted with ethyl acetate
  4. washThe organic phase was washed with brine
  5. dry with materialdried over magnesium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe residue was purified by silica gel chromatography (6% ethyl acetate/petroleum ether elute)

Sources & evidence

ORD record
ord-e91d854fd6b447478592c943242f4a2c
Source dataset
uspto-grants-2015_06
Patent number
US09067914B1

Reaction notes

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