1-Tetralone → Ethyl 1-oxo-3,4-dihydro-1H-spiro[naphthalene-2,4'-piperidine]-1'-carboxylate

HRID 1591158Notes

Reaction equation

HRID 1591158 reaction equation
[C:1]1(=[O:11])[C:10]2[C:5](=[CH:6][CH:7]=[CH:8][CH:9]=2)[CH2:4][CH2:3][CH2:2]1.Br[CH2:13][CH2:14][N:15]([CH2:21][CH2:22]Br)[C:16](=[O:20])[O:17][CH2:18][CH3:19].[H-].[Na+]>CN(C)C=O>[CH2:18]([O:17][C:16]([N:15]1[CH2:21][CH2:22][C:2]2([CH2:3][CH2:4][C:5]3[C:10](=[CH:9][CH:8]=[CH:7][CH:6]=3)[C:1]2=[O:11])[CH2:13][CH2:14]1)=[O:20])[CH3:19]

Participants

5

Reactant 3

HCID 107241-TetraloneHCID 24758Sodium hydrideHCID 10924683Ethyl bis(2-bromoethyl)carbamate

Product 1

HCID 53766172Ethyl 1-oxo-3,4-dihydro-1H-spiro[naphthalene-2,4'-piperidine]-1'-carboxylateYield 26%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
50 °C

Procedure

To a solution of 2.92 g (20.0 mmoles) 1-tetralone and 9.0 g (30.0 mmoles) ethyl bis(2-bromoethyl)carbamate (S. Huybuchts and G. J. Hoornaert, Synth. Commum., 11, 17 (1981) in 20 ml dry dimethylformamide heated to 50° C. under argon was added in portions 2.00 g (50.0 mmol) of 60% sodium hydride dispersion is mineral oil. The mixture was stirred 14 hours at 50° C. and the solvent was removed in vacuo. The residue was taken up in 50 ml ether, quenched with 5 ml saturated ammonium chloride solution, diluted with 10 ml water, and the layers were separated. The aqueous layer was extracted with 2×50 ml ether. The combined extracts were washed with 2×15 ml water and brine, dried, and the solvent was removed in vacuo to give 7.77 g crude product as an oil. This was purified by flash chromatography on silica gel eluting with ethyl acetate: hexane (30:70) to give 1.47 g (26%) product as an oil; 'H NMR (deuteriochloroform): δ1.26 (t, 3H), 1.52 (m, 2H), 1.97 (m, 2H), 2.06 (t,2H), 3.01 (t, 3H), 3.59 (m, 4H), 4.14 (q, 2H), 7.24 (t, 1H), 7.31 (t, 1H), 7.97 (m, 1H), 8.01 (d, 1H).

Workup

  1. customthe solvent was removed in vacuo
  2. customquenched with 5 ml saturated ammonium chloride solution
  3. additiondiluted with 10 ml water
  4. customthe layers were separated
  5. extractionThe aqueous layer was extracted with 2×50 ml ether
  6. washThe combined extracts were washed with 2×15 ml water and brine
  7. customdried
  8. customthe solvent was removed in vacuo
  9. customto give 7.77 g crude product as an oil
  10. customThis was purified by flash chromatography on silica gel eluting with ethyl acetate: hexane (30:70)

Sources & evidence

ORD record
ord-a86cab9c5d9c4a79afa67c9b7a84defb
Source dataset
uspto-grants-1993_04
Patent number
US05206240

Reaction notes

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