Methyl iodide → Tert-butyl 4-methyl-3-oxopiperazine-1-carboxylate

HRID 1108566Notes

Reaction equation

HRID 1108566 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][NH:11][C:10](=[O:14])[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH3:15]C(C)([O-])C.[K+].IC>CN(C=O)C>[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([CH3:15])[C:10](=[O:14])[CH2:9]1)=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

5

Reactant 3

HCID 6328Methyl iodideHCID 3157178Tert-butyl 3-oxopiperazine-1-carboxylateHCID 23665647Potassium tert-butoxide

Product 1

HCID 18783916Tert-butyl 4-methyl-3-oxopiperazine-1-carboxylateYield 73.3%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

1-tert-Butoxycarbonyl-3-oxopiperazine (see Tetrahedron Lett. (1980), 21(32), 3019-20 for outline of synthesis, 5 g) was dissolved in dry DMF (75 ml) and potassium tert-butoxide (3.08 g) was added. The mixture was stirred at ambient temperature for 1 hour, then iodomethane (3.9 g) was added, and stirring continued at the same temperature for 2.5 hours. Solvent was evaporated, and the residue chromatographed on silica, using as eluant a gradient increasing in polarity from 0 to 100% ethyl acetate in iso-hexane. Relevant fractions were combined and evaporated to give 1-tert-butoxycarbonyl-4-methyl-3-oxopiperazine (3.92 g).

Workup

  1. stirringstirring
  2. waitcontinued at the same temperature for 2.5 hours
  3. customSolvent was evaporated
  4. customthe residue chromatographed on silica
  5. temperaturea gradient increasing in polarity from 0 to 100% ethyl acetate in iso-hexane
  6. customevaporated

Sources & evidence

ORD record
ord-5d42a03af54f46bbab768f2f59cea513
Source dataset
uspto-grants-2000_05
Patent number
US06069145

Reaction notes

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