2-Methylresorcinol → 2,4-Dihydroxy-3-methylbenzaldehyde

HRID 728232Notes

Reaction equation

HRID 728232 reaction equation
P(Cl)(Cl)(Cl)=O.CN([CH:14]=[O:15])C1C=CC=CC=1.[CH3:16][C:17]1[C:23]([OH:24])=[CH:22][CH:21]=[CH:20][C:18]=1[OH:19]>CCOCC>[OH:19][C:18]1[C:17]([CH3:16])=[C:23]([OH:24])[CH:22]=[CH:21][C:20]=1[CH:14]=[O:15]

Participants

5

Reactant 3

HCID 118432-MethylresorcinolHCID 24813Phosphorus oxychlorideHCID 66737N-Methylformanilide

Product 1

HCID 803952,4-Dihydroxy-3-methylbenzaldehydeYield 57%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

Phosphorus oxychloride (80 mL, 0.86 mol) was added to a stirred mixture of N-methylformanilide (102 mL, 0.82 mol) in ether (250 mL). The mixture was stirred for 1 hour at room temperature and then cooled in ice. 2-Methyl resorcinol (Aldrich, 100 g 0.81 mol) was added and the mixture was allowed to warm to room temperature while stirring overnight. The precipitated intermediate product was collected by filtration and rinsed with ether (3×). The intermediate was hydrolyzed by dissolving in a mixture of acetone (250 mL) and water (250 mL) and stirring for 30 minutes. Water (2 L) was added, the mixture was brought to a boil, and then allowed to cool and deposit crystalline product. This was recrystallized a second time from water (4 L) to afford pure product (70 g, 57%). M.p. 150° C. (Lit. 152°-3° C. [W. Baker et al., J. Chem. Soc., 2834-5 (1949)⟧ NMR (DMSO-d6): δ 1.973 (s, 3H), 6.551 (d, J=8.5 hz, 1H), 7.428 (d, J-8.5 hz, 1H), 9.703 (s, 1H), 10.745 (s, 1H), and 11.592 (s, 1H),

Workup

  1. temperaturecooled in ice
  2. temperatureto warm to room temperature
  3. stirringwhile stirring overnight
  4. filtrationThe precipitated intermediate product was collected by filtration
  5. washrinsed with ether (3×)
  6. dissolutionby dissolving in a mixture of acetone (250 mL) and water (250 mL)
  7. stirringstirring for 30 minutes
  8. additionWater (2 L) was added
  9. temperatureto cool
  10. customThis was recrystallized a second time from water (4 L)

Sources & evidence

ORD record
ord-42c8b996c3054e35a46b15c626332566
Source dataset
uspto-grants-1991_09
Patent number
US05047519

Reaction notes

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