Benzyl Bromide → 1-Benzylazepan-2-one

HRID 1593091Notes

Reaction equation

HRID 1593091 reaction equation
[H-].[Na+].[NH:3]1[CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][C:4]1=[O:10].[CH2:11](Br)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1>C1COCC1>[CH2:11]([N:3]1[CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][C:4]1=[O:10])[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1

Participants

5

Procedure

To a stirring 0° C. suspension of NaH (18.3 g, 763 mmol) in THF (195 mL) was added by addition funnel azepan-2-one (75.0 g, 667 mmol) in THF. An additional 2L of solvent was added as the reaction progressed in order to maintain agitation of the very viscous reaction suspension. Following addition, the reaction was allowed to warm to room temperature, and when the evolution of H2 gas ceased after stirring overnight, benzyl bromide was added dropwise by addition funnel and the reaction was stirred overnight. The crude product was filtered through Celite and concentrated in vacuo. Recrystallization from hexanes and ethyl acetate provided pure 1-benzyl-azepan-2-one as a white fluffy solid. 1H NMR (CDCl3, 300 MHz) 7.38-7.24 (5H, m), 4.61 (2H, s), 3.33-3.29 (2H, m), 2.65-2.61 (2H, m), 1.77-1.66 (4H, m), 1.56-1.46 (2H, m) ppm. 13C NMR (CDCl3, 75 MHz) 176.13, 138.06, 128.67, 128.31, 127.43, 51.20, 49.04, 37.33, 30.12, 28.26, 23.58 ppm.

Workup

  1. temperatureto maintain agitation of the very viscous reaction suspension
  2. additionaddition
  3. stirringthe reaction was stirred overnight
  4. filtrationThe crude product was filtered through Celite
  5. concentrationconcentrated in vacuo
  6. customRecrystallization from hexanes and ethyl acetate provided pure 1-benzyl-azepan-2-one as a white fluffy solid

Sources & evidence

ORD record
ord-1627141a23ce41f4b596ee2120b72fe2
Source dataset
uspto-grants-2007_11
Patent number
US07294637B2

Reaction notes

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