1-Chloroethyl chloroformate → 3-Cyclopropyl-6,7,8,9-tetrahydropyrazino[2,3-f][1,4]oxazepine hydrochloride

HRID 2188703Notes

Reaction equation

HRID 2188703 reaction equation
C([N:8]1[CH2:14][C:13]2[N:15]=[CH:16][C:17]([CH:19]3[CH2:21][CH2:20]3)=[N:18][C:12]=2[O:11][CH2:10][CH2:9]1)C1C=CC=CC=1.[Cl:22]C(OC(Cl)C)=O>C1(C)C=CC=CC=1>[ClH:22].[CH:19]1([C:17]2[CH:16]=[N:15][C:13]3[CH2:14][NH:8][CH2:9][CH2:10][O:11][C:12]=3[N:18]=2)[CH2:21][CH2:20]1

Participants

4

Reactant 2

HCID 5213051-Chloroethyl chloroformateHCID 669933158-Benzyl-3-cyclopropyl-6,7,8,9-tetrahydropyrazino[2,3-f][1,4]oxazepine

Product 1

HCID 669934443-Cyclopropyl-6,7,8,9-tetrahydropyrazino[2,3-f][1,4]oxazepine hydrochlorideYield 16%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
100 °C

Procedure

To a solution of 8-benzyl-3-cyclopropyl-6,7,8,9-tetrahydropyrazino[2,3-f][1,4]oxazepine (79.9 mg) in toluene (3 mL) was added 1-chloroethyl chloroformate (0.033 mL), and the mixture was stirred at 100° C. for 3 hr. The reaction mixture was cooled to room temperature, and concentrated. To the obtained residue was added methanol (3 mL) and the mixture was stirred at 60° C. for 2 hr. The reaction mixture was cooled to room temperature, and concentrated. The concentrate was diluted with ethyl acetate, and washed with saturated aqueous sodium hydrogen carbonate, water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was purified by basic silica gel column chromatography (solvent gradient; 10→100% ethyl acetate/hexane). To a solution of the obtained oil in methanol (1 mL) was added 0.1 N hydrochloric acid (0.6 mL), and the mixture was concentrated under reduced pressure. The obtained crude crystals were purified by recrystallization (ethanol-diisopropyl ether) to give the title compound (10.2 mg, 16%) as colorless crystals.

Workup

  1. temperatureThe reaction mixture was cooled to room temperature
  2. concentrationconcentrated
  3. additionTo the obtained residue was added methanol (3 mL)
  4. stirringthe mixture was stirred at 60° C. for 2 hr
  5. temperatureThe reaction mixture was cooled to room temperature
  6. concentrationconcentrated
  7. additionThe concentrate was diluted with ethyl acetate
  8. washwashed with saturated aqueous sodium hydrogen carbonate, water and saturated brine
  9. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  10. concentrationconcentrated under reduced pressure
  11. customThe obtained residue was purified by basic silica gel column chromatography (solvent gradient; 10→100% ethyl acetate/hexane)
  12. additionTo a solution of the obtained oil in methanol (1 mL) was added 0.1 N hydrochloric acid (0.6 mL)
  13. concentrationthe mixture was concentrated under reduced pressure
  14. customThe obtained crude crystals
  15. customwere purified by recrystallization (ethanol-diisopropyl ether)

Sources & evidence

ORD record
ord-0bba6d327d80443a9e4d468ce1b91848
Source dataset
uspto-grants-2012_12
Patent number
US08324201B2

Reaction notes

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