Sulfuric Acid → N-carbobenzoxy-D-alanine(1-methyl-1-cyclopentyl)ester

HRID 620688

Reaction equation

HRID 620688 reaction equation
[C:1]([NH:11][C@@H:12]([C:14]([OH:16])=[O:15])[CH3:13])([O:3][CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1)=[O:2].S(=O)(=O)(O)O.[CH3:22][C:23]1[CH2:27][CH2:26][CH2:25][CH:24]=1>ClCCl>[CH3:22][C:23]1([O:15][C:14](=[O:16])[C@@H:12]([CH3:13])[NH:11][C:1]([O:3][CH2:4][C:5]2[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=2)=[O:2])[CH2:27][CH2:26][CH2:25][CH2:24]1

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 127461-MethylcyclopenteneHCID 70832N-Cbz-d-alanine

Product 1

HCID 22839475N-carbobenzoxy-D-alanine(1-methyl-1-cyclopentyl)ester

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a magnetically stirred solution of 22.3 g (0.1 mol) N-Cbz-D-alanine in 50 mls of dry dichloromethane containing 0.5 mls of concentrated sulfuric acid at 0° C., was added dropwise a 10 g (0.1 mol) sample of 1-methylcyclopentene in 50 mls of dichloromethane. After 5 days of stirring at room temperature, the mixture was heated to reflux for 4 hours, after which the reaction was cooled to room temperature, washed with 100 mls of saturated NaHCO3, 100 mls of water and dried over MgSO4. Filtration followed by evaporation of the solvent yielded 1.81 g of the product. NMR(CDCl3): δ1.3-1.4 (d, 3H), 1.5 (s, 3H), 1.5-1.7 (m, 8H), 4.2 (m, 1H), 5.05 (s, 2H), 5.25 (m, 1H), 7.3 (s, 5H).

Workup

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 4 hours
  3. temperatureafter which the reaction was cooled to room temperature
  4. washwashed with 100 mls of saturated NaHCO3, 100 mls of water
  5. dry with materialdried over MgSO4
  6. filtrationFiltration
  7. customfollowed by evaporation of the solvent

Sources & evidence

ORD record
ord-818ad3fe93584082b34aef5512667bcd
Source dataset
uspto-grants-1989_04
Patent number
US04822635

Linked notes

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