Cornforth reagent → tert-Butyl methyl(4-oxobutyl)carbamate

HRID 2248622Notes

Reaction equation

HRID 2248622 reaction equation
[OH:1][CH2:2][CH2:3][CH2:4][CH2:5][N:6]([CH3:14])[C:7](=[O:13])[O:8][C:9]([CH3:12])([CH3:11])[CH3:10].[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1>ClCCl>[CH3:14][N:6]([CH2:5][CH2:4][CH2:3][CH:2]=[O:1])[C:7](=[O:13])[O:8][C:9]([CH3:12])([CH3:10])[CH3:11]

Participants

4

Reactant 2

HCID 2724130Cornforth reagentHCID 14854943tert-Butyl (4-hydroxybutyl)(methyl)carbamate

Product 1

HCID 15078448tert-Butyl methyl(4-oxobutyl)carbamateYield 70%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

A solution of 50 parts of (1,1-dimethylethyl) (4-hydroxybutyl)methylcarbamate in 91 parts of dichloromethane was added dropwise to a mixture of 150 parts of pyridinium dichromate, 112 parts of molecular sieves and 1300 parts of dichloromethane at a temperature about 10° C. Upon completion, stirring was continued for 3 hours at room temperature. The reaction mixture was filtered, washed with 1,1'-oxybisethane and the filtrate was evaporated. The residue was purified by column chromatography over silica gel using dichloromethane as eluent. The pure fractions were collected and the eluent was evaporated with methylbenzene, yielding 35 parts (70%) of (1,1-dimethylethyl) methyl(4-oxobutyl)carbamate as a residue (int. 38).

Workup

  1. filtrationThe reaction mixture was filtered
  2. washwashed with 1,1'-oxybisethane
  3. customthe filtrate was evaporated
  4. customThe residue was purified by column chromatography over silica gel
  5. customThe pure fractions were collected
  6. customthe eluent was evaporated with methylbenzene

Sources & evidence

ORD record
ord-6333324afbd543bc85d35f00cbeab497
Source dataset
uspto-grants-1991_08
Patent number
US05041454

Reaction notes

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