Dimethyl malonate → Benzoic acid, 2,4-dihydroxy-3-methyl-, methyl ester

HRID 267817Notes

Reaction equation

HRID 267817 reaction equation
ClN1CCCCCC1=O.Cl[CH2:11][CH2:12][C:13](=[O:16])[CH2:14][CH3:15].[C:17](OC)(=[O:23])[CH2:18][C:19]([O:21][CH3:22])=[O:20]>C1C=CC=CC=1>[CH3:15][C:14]1[C:17]([OH:23])=[C:18]([C:19]([O:21][CH3:22])=[O:20])[CH:11]=[CH:12][C:13]=1[OH:16]

Participants

5

Reactant 3

HCID 7943Dimethyl malonateHCID 880611-Chlorohexahydro-2H-azepin-2-oneHCID 965263-Pentanone, 1-chloro-

Product 1

HCID 118521Benzoic acid, 2,4-dihydroxy-3-methyl-, methyl esterYield 85%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Conditions

Temperature
30 °C

Procedure

In a 1-L three-necked flask fitted with a mechanical stirrer and a reflux condenser protected by a calcium chloride drying tube, are placed a solution of 60.5 g of N-chlorocaprolactam in 400 ml of benzene and 75.5 g of methyl 3-methyl-dihydroresorcylate, prepared from 5-chloropentan-3-one (R. B. Woodward et al., J.Am.Chem.Soc. 74, 4223 (1952)) and dimethyl malonate; m.p. 126.5° - 127.9° C. The reaction mixture is stirred at reflux temperature for 8 hours, then cooled to 30° C, transferred to a separatory funnel and washed successively with water, 0.2 molar sodium carbonate solution and again with water. The organic layer is then cooled to 5° C and extracted with cold 0.4N sodium hydroxide solution. The aqueous solution is acidified with a slight excess of 15% hydrochloric acid. The temperature is maintained at 0° C throughout the acidification. The solid product is filtered off, washed thoroughly with water and dried, yielding 63.5 g (85%) of methyl 3-methyl-resorcylate (identified by NMR, IR and mass spectral analysis). M.p. 130.5° - 131.6° C).

Workup

  1. customIn a 1-L three-necked flask fitted with a mechanical stirrer and a reflux condenser
  2. customprotected by a calcium chloride drying tube
  3. temperatureat reflux temperature for 8 hours
  4. customtransferred to a separatory funnel
  5. washwashed successively with water, 0.2 molar sodium carbonate solution and again with water
  6. temperatureThe organic layer is then cooled to 5° C
  7. extractionextracted with cold 0.4N sodium hydroxide solution
  8. temperatureThe temperature is maintained at 0° C throughout the acidification
  9. filtrationThe solid product is filtered off
  10. washwashed thoroughly with water
  11. customdried

Sources & evidence

ORD record
ord-afb8a99ca82d483c9b86c7003b1769d3
Source dataset
uspto-grants-1976_03
Patent number
US03944596

Reaction notes

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