Dimethylformamide → N,N'-Dicyclohexylurea

HRID 1769307Notes

Reaction equation

HRID 1769307 reaction equation
CN(C=[O:5])C.FC1C(O)=C(F)C(F)=C(F)C=1F.[CH:18]1([N:24]=[C:25]=[N:26][CH:27]2[CH2:32][CH2:31][CH2:30][CH2:29][CH2:28]2)[CH2:23][CH2:22][CH2:21][CH2:20][CH2:19]1>C(#N)C>[C:25]([NH:24][CH:18]1[CH2:19][CH2:20][CH2:21][CH2:22][CH2:23]1)([NH:26][CH:27]1[CH2:32][CH2:31][CH2:30][CH2:29][CH2:28]1)=[O:5]

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 10868DicyclohexylcarbodiimideHCID 13041Pentafluorophenol

Product 1

HCID 4277N,N'-Dicyclohexylurea

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

Suspended in 200 ml of acetonitrile are N-(9-fluorenylmethoxycarbonyl)-4-L-hydroxyproline (20.5 g, 50 mmol), followed by the addition of 12 ml of N, N'-dimethylformamide under ice cooling. The resulting mixture is stirred, to which 11.9 g (1.1 equivalents) of pentafluorophenol and 13.2 g (1.1 equivalents) of dicyclohexylcarbodiimide are added. The resulting suspension is stirred for one hour and then, stirred overnight at room temperature. Dicyclohexylurea produced by the reaction is removed by filtration and the filtrate is concentrated. The concentrate is dissolved in ethyl acetate. Dicyclohexylurea, which remained undissolved, is removed by filtration. The operations of dissolution in ethyl acetate, filtration, and concentration are additionally repeated twice. N,N'-Dimethylformamide contained in the concentrate is completely distilled off under reduced pressure. The concentrate is dissolved in ethyl acetate, and to the resulting solution is added n-hexane for re-precipitation, whereby 28.0 g of the product is obtained (yield: 93%).

Workup

  1. additionare added
  2. stirringstirred overnight at room temperature

Sources & evidence

ORD record
ord-b8a4fec150e84f62920deb465639012a
Source dataset
uspto-grants-1995_01
Patent number
US05380875

Reaction notes

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