Di-tert-butyl dicarbonate → HCID 18914284, compound

HRID 1292123Notes

Reaction equation

HRID 1292123 reaction equation
[CH3:1][CH:2]1[CH2:7][C:6](=[O:8])[CH:5]=[CH:4][N:3]1[C:9]([O:11][CH2:12][C:13]1[CH:18]=CC=C[CH:14]=1)=[O:10].C(OC(OC(OC(C)(C)C)=O)=O)(C)(C)C.[H][H]>[Pd].C(OCC)(=O)C>[CH3:14][CH:13]([CH3:18])[CH2:12][O:11][C:9]([N:3]1[CH2:4][CH2:5][C:6](=[O:8])[CH2:7][CH:2]1[CH3:1])=[O:10]

Participants

6

Reactant 3

HCID 90495Di-tert-butyl dicarbonateHCID 11459227Benzyl 2-methyl-4-oxo-3,4-dihydropyridine-1(2H)-carboxylateHCID 178418361HCID 178418361, compound

Product 1

HCID 18914284HCID 18914284, compoundYield 20.9%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 8857Ethyl AcetateSolvent

Procedure

A mixture of 1.1 g of the crude 2(R,S)-methyl-1(benzyloxycarbonyl)-2,3-dihydro-4-pyridone, 200 mL of ethyl acetate, 1 g of di-tert-butyldicarbonate and 1 g of 10% palladium on carbon was shaken under 55 psi of hydrogen for 24 h. The mixture was filtered, concentrated under reduced pressure, and purified by low pressure chromatography on silica gel eluting with 40% ethyl acetate in hexane. There was obtained first 0.20 g of (±)-1-(2,2-dimethylethoxycarbonyl)-2-methyl-4-oxopiperidine: 1H NMR (400 MHz, CDCl3) 4.65 (m, 1H), 4.2 (m, 1H), 3.3 (m, 1H), 2.65 (dd, 1H), 2.45 (m, 1H), 2.3 (m, 1H), 2.2 (dd, 1H), 1.45 (s, 9H), 1.14 (d, 3H). Later fractions gave 0.50 g of the (±)-1-(2,2-dimethylethoxycarbonyl)-2-methyl-4-hydroxypiperidine: 1H NMR (400 MHz, CDCl3) 4.3 (m, 1H), 4.15 (t, 1H), 3.8 (m, 1H), 3.25 (m, 1H), 2.15 (s, 1H), 2.8 (m, 1H), 1.65 (m, 3H), 1.42 (s, 3H), 1.25 (d, 3H).

Workup

  1. filtrationThe mixture was filtered
  2. concentrationconcentrated under reduced pressure
  3. custompurified by low pressure chromatography on silica gel eluting with 40% ethyl acetate in hexane

Sources & evidence

ORD record
ord-df522161a0c04627a65240b915a7976b
Source dataset
uspto-grants-1998_05
Patent number
US05756508

Reaction notes

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