Allyl-(1-methyl-pent-4-enyl)-carbamic acid benzyl ester → Benzyl 2-methyl-2,3,4,7-tetrahydro-1H-azepine-1-carboxylate

HRID 229802Notes

Reaction equation

HRID 229802 reaction equation
[CH2:1]([O:8][C:9](=[O:20])[N:10]([CH2:17][CH:18]=C)[CH:11](C)[CH2:12][CH2:13][CH:14]=[CH2:15])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>C(Cl)Cl.C=CC1C=CC=CC=1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.Cl[Ru]Cl>[CH2:1]([O:8][C:9]([N:10]1[CH2:11][CH:12]=[CH:13][CH2:14][CH2:15][CH:17]1[CH3:18])=[O:20])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

4

Reactant 1

HCID 11608774Allyl-(1-methyl-pent-4-enyl)-carbamic acid benzyl ester

Product 1

HCID 11586812Benzyl 2-methyl-2,3,4,7-tetrahydro-1H-azepine-1-carboxylateYield 92%

Reagents, catalysts & solvents 2

HCID 60145889Benzylidene-bis(triphenylphosphine)ruthenium dichlorideCatalyst2×HCID 6344DichloromethaneSolvent

Procedure

Allyl-(1-methyl-pent-4-enyl)-carbamic acid benzyl ester (0.872 g, 3.19 mmol) was dissolved in CH2Cl2 (10 ml) and a stream of argon gas was bubbled into the reaction mixture for 10 minutes. Then bis(tricyclohexylphosphine)benzylidine ruthenium(IV) dichloride (Strem Chemicals, Grubbs' catalyst, 19 mg, 0.0227 mmol) was added and the reaction mixture was refluxed for 2 h. Additional bis(tricyclohexylphosphine)benzylidine ruthenium(IV) dichloride (mg, 0.0108 mmol) was added and the reaction mixture was refluxed for an additional 1.5 hours. The reaction was cooled to RT under argon overnight, then was concentrated in vacuo by rotary evaporation, then was chromatographed (silica gel, 5% EtOAc/hexanes) to give the title compound (0.72 g, 92%): 1H NMR: 7.35-7.20 (m, 5H), 5.65 (1H, m), 5.13 (2H, AB), 4.45-4.05 (m, 2H), 3.56 (1H, d), 2.25-2.10 (m, 2H), 1.90-1.60 (m, 2H), 1.12 (3H, d); Liquid Chromatgraphy/Electrospray mass spec: M+H+=246.2.

Workup

  1. customa stream of argon gas was bubbled into the reaction mixture for 10 minutes
  2. temperaturethe reaction mixture was refluxed for 2 h
  3. temperaturethe reaction mixture was refluxed for an additional 1.5 hours
  4. concentrationwas concentrated in vacuo by rotary evaporation
  5. customwas chromatographed (silica gel, 5% EtOAc/hexanes)

Sources & evidence

ORD record
ord-d000d78496f54fe3a788c55061ebd08d
Source dataset
uspto-grants-2009_07
Patent number
US07563784B2

Reaction notes

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