Chloride → (S)-(-)-2-t-Butyl-2-piperazinecarboxamide

HRID 1586533

Reaction equation

HRID 1586533 reaction equation
[C:1]([NH:5][C:6]([C:8]1[CH:13]=[N:12][CH:11]=[CH:10][N:9]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[Cl-]>CO>[C:1]([NH:5][C:6]([C@@H:8]1[CH2:13][NH:12][CH2:11][CH2:10][NH:9]1)=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

4

Reactant 2

HCID 312ChlorideHCID 4462842N-tert-butylpyrazine-2-carboxamide

Product 1

HCID 9806153(S)-(-)-2-t-Butyl-2-piperazinecarboxamide

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

0.5 g (2.7 mmol) of pyrazinecarboxylic acid tert-butylamide (prepared according to Example 3), 26.9 mg (58 μmol) of bicyclo[2.2.1]hepta-2,5-dienerhodium(I) chloride dimer and 72 mg (121 μmol) of 1-[1 (R)-(dicyclohexylphosphino)ethyl]-2(S)-(diphenylphosphino)ferrocene were placed in an autoclave under argon. After the addition of 10 ml of degassed methanol, the autoclave was flushed three times with argon and twice with hydrogen. A hydrogen pressure of 50 bar was then applied. Hydrogenation was carried out at 70° C. for 20 hours. The autoclave was depressurized and flushed with nitrogen. The solvent was completely distilled off. The yield of the title compound was 0.50 g. A conversion of 80 percent was determined by NMR. The enantiomeric excess (ee) was 77.6 percent according to GC analysis.

Workup

  1. customthe autoclave was flushed three times with argon
  2. customflushed with nitrogen
  3. distillationThe solvent was completely distilled off

Sources & evidence

ORD record
ord-5c436cb535344985a936f615956edea5
Source dataset
uspto-grants-1999_08
Patent number
US05945534

Linked notes

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