Diethyl Ether → Di-tert-butyl (2-formyl-1,4-phenylene)dicarbamate

HRID 394413Notes

Reaction equation

HRID 394413 reaction equation
[C:1]([O:5][C:6]([NH:8][C:9]1[CH:14]=[CH:13][C:12]([NH:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])=[CH:11][C:10]=1Br)=[O:7])([CH3:4])([CH3:3])[CH3:2].C([Li])(C)(C)C.CN(C)[CH:31]=[O:32].CCOCC>O>[C:1]([O:5][C:6](=[O:7])[NH:8][C:9]1[CH:14]=[CH:13][C:12]([NH:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])=[CH:11][C:10]=1[CH:31]=[O:32])([CH3:4])([CH3:3])[CH3:2]

Participants

6

Reactant 4

HCID 3283Diethyl EtherHCID 6228DimethylformamideHCID 154289672,5-Bis-tert.-butyloxycarbonylaminobromobenzeneHCID 178418306HCID 178418306, compound

Product 1

HCID 15539052Di-tert-butyl (2-formyl-1,4-phenylene)dicarbamate

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
-20 °C

Procedure

3.3 g (0.01 mol) 2,5-bis-tert.-butyloxycarbonylamino-bromobenzene from step A are dissolved in 100 ml of water-free tetrahydrofuran under argon. Gradually 17 ml of a 1.6 molar methyl lithium ether solution (0.03 mol) are added. The reaction mixture is cooled to −20° C. Subsequently 7 ml of 1.5 molar t-butyl lithium solution (0.01 mol) are added gradually. After ending the addition the solution is stirred for 30 minutes at −20° C. Subsequently 1.2 g of dimethylformamide (0.02 mol) are added and the reaction mixture is stirred for an hour at −20° C. After slow heating to room temperature the reaction mixture is hydrolyzed with water and then poured into ether, the aqueous phase is extracted with ether and then the organic phase is dried with magnesium sulfate. The solvent is distilled off in a rotary evaporator and the residue is purified on silica gel with petroleum ether/ethyl acetate (9:1).

Workup

  1. additionthe addition the solution
  2. stirringthe reaction mixture is stirred for an hour at −20° C
  3. temperatureAfter slow heating to room temperature the reaction mixture
  4. extractionthe aqueous phase is extracted with ether
  5. dry with materialthe organic phase is dried with magnesium sulfate
  6. distillationThe solvent is distilled off in a rotary evaporator
  7. customthe residue is purified on silica gel with petroleum ether/ethyl acetate (9:1)

Sources & evidence

ORD record
ord-3d2e707a52874193af73980bbf7a3e3a
Source dataset
uspto-grants-2003_08
Patent number
US06602302B1

Reaction notes

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