1,4-Dichlorobenzene → HCID 19741711, compound

HRID 2255118Notes

Reaction equation

HRID 2255118 reaction equation
[C:1]([NH:4][CH:5]([C:10]1[CH:15]=[CH:14][CH:13]=[C:12]([O:16]CC=C)[CH:11]=1)[C:6]([O:8][CH3:9])=[O:7])(=[O:3])[CH3:2].[CH:20]1[C:25](Cl)=CC=C(Cl)[CH:21]=1>>[C:1]([NH:4][CH:5]([C:10]1[CH:15]=[CH:14][C:13]([CH2:25][CH:20]=[CH2:21])=[C:12]([OH:16])[CH:11]=1)[C:6]([O:8][CH3:9])=[O:7])(=[O:3])[CH3:2]

Participants

3

Reactant 2

HCID 46851,4-DichlorobenzeneHCID 19741706HCID 19741706, compound

Product 1

HCID 19741711HCID 19741711, compound

Conditions

Temperature
350 °C

Procedure

A solution of methyl α-(acetylamino)-3-(2-propenoxy)benzeneacetate from Preparation 5 above (8.0 g, 32 mmol) in 15 g of p-dichlorobenzene is heated at 350° C. for 16 hours in a sealed tube. The reaction mixture is cooled and the contents of the tube are purified by silica gel chromatography, eluting with CHCl3 to remove the p-dichlorobenzene and then with 5% MeOH-CHCl2 to remove the rearrangement products (methyl α-(acetylamino)-3-hydroxy-2-(2-propenyl) benzeneacetate, methyl α-(acetylamino)-3-hydroxy-4-(2-propenyl)benzeneacetate). The rearrangement products (a 1:1 mixture of methyl α-(acetylamino)-3-hydroxy-2-(2-propenyl)-benzeneacetate, methyl α-(acetylamino)-3-hydroxy-4-(2propenyl)benzeneacetate) are separated by silica gel chromatography (Chromatotron/EtOAc). Recrystallization from diisopropylether/THF gives the compound of methyl α-(acetylamino)-3-hydroxy-4-(2-propenyl)benzeneacetate above (2.60 g, 33%) as a white solid, mp 143°-145° C.

Workup

  1. temperatureThe reaction mixture is cooled
  2. customthe contents of the tube are purified by silica gel chromatography
  3. washeluting with CHCl3
  4. customto remove the p-dichlorobenzene
  5. customwith 5% MeOH-CHCl2 to remove the rearrangement products (methyl α-(acetylamino)-3-hydroxy-2-(2-propenyl) benzeneacetate, methyl α-(acetylamino)-3-hydroxy-4-(2-propenyl)benzeneacetate)
  6. additionThe rearrangement products (a 1:1 mixture of methyl α-(acetylamino)-3-hydroxy-2-(2-propenyl)-benzeneacetate, methyl α-(acetylamino)-3-hydroxy-4-(2propenyl)benzeneacetate)
  7. customare separated by silica gel chromatography (Chromatotron/EtOAc)
  8. customRecrystallization from diisopropylether/THF

Sources & evidence

ORD record
ord-59ec9d812beb40d7a5deed6d20db838b
Source dataset
uspto-grants-1993_08
Patent number
US05238958

Reaction notes

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