Sodium Chloride → 16-(2-Hydroxy-3,4-dimethoxy-6-methylphenyl)hexadecanoic acid

HRID 2412847Notes

Reaction equation

HRID 2412847 reaction equation
S1(CCCC1)(=O)=O.C1(C)C=CC(S(O)(=O)=O)=CC=1.O=[C:20]([CH2:29][CH2:30][CH2:31][CH2:32][CH2:33][CH2:34][CH2:35][CH2:36][CH2:37][C:38]1[C:43]([CH3:44])=[CH:42][C:41]([O:45][CH3:46])=[C:40]([O:47][CH3:48])[C:39]=1[OH:49])[CH2:21][CH2:22][CH2:23][CH2:24][CH2:25][C:26]([OH:28])=[O:27].C([BH3-])#N.[Na+].[Cl-].[Na+]>C1CCCCC1.CN(C)C=O>[OH:49][C:39]1[C:40]([O:47][CH3:48])=[C:41]([O:45][CH3:46])[CH:42]=[C:43]([CH3:44])[C:38]=1[CH2:37][CH2:36][CH2:35][CH2:34][CH2:33][CH2:32][CH2:31][CH2:30][CH2:29][CH2:20][CH2:21][CH2:22][CH2:23][CH2:24][CH2:25][C:26]([OH:28])=[O:27]

Participants

8

Reactant 5

HCID 5234Sodium ChlorideHCID 6101p-Toluenesulfonic acidHCID 31347SulfolaneHCID 5003444Sodium cyanoborohydrideHCID 133705097-Oxo-16-(2-hydroxy-3,4-dimethoxy-6-methylphenyl)hexadecanoic acid

Product 1

HCID 1337050816-(2-Hydroxy-3,4-dimethoxy-6-methylphenyl)hexadecanoic acidYield 57.3%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8078CyclohexaneSolvent

Procedure

To a solvent mixture of dimethylformamide (10 ml) and sulfolane (10 ml) containing p-toluenesulfonic acid (100 mg) is added 7-oxo-16-(2-hydroxy-3,4-dimethoxy-6-methylphenyl)hexadecanoic acid (1.75 g) and p-toluenesulfonyl hydrazide (930 mg) at 100° C. After 5 minutes, cyclohexane (10 ml) and sodium cyanoborohydride (1.0 g) are added. The reaction is conducted at 100° C. for 20 minutes. Then, at room temperature, a saturated aqueous solution of sodium chloride (100 ml) is added, followed by extraction with ether (50 ml×2). The ether layers are combined, washed with water, 1N--HCl and water in that order, and dried over anhydrous sodium sulfate. The solvent is distilled off, and the residue is dissolved in chloroform and subjected to column chromatography on silica gel, elution being carried out with chloroform. The fractions containing the desired compound are pooled and the solvent is distilled off. To the crystalline residue is added petroleum ether and, after cooling, the crystals are collected by filtration. The above procedure yields 970 mg of 16-(2-hydroxy-3,4-dimethoxy-6-methylphenyl)hexadecanoic acid, m.p. 45° C.-46° C.

Workup

  1. waitThe reaction is conducted at 100° C. for 20 minutes
  2. extractionfollowed by extraction with ether (50 ml×2)
  3. washwashed with water, 1N
  4. dry with materialHCl and water in that order, and dried over anhydrous sodium sulfate
  5. distillationThe solvent is distilled off
  6. dissolutionthe residue is dissolved in chloroform
  7. washsubjected to column chromatography on silica gel, elution
  8. additionThe fractions containing the desired compound
  9. distillationthe solvent is distilled off
  10. additionTo the crystalline residue is added petroleum ether
  11. temperatureafter cooling
  12. filtrationthe crystals are collected by filtration

Sources & evidence

ORD record
ord-96c32b8f62a141a089cb4126ef5a141b
Source dataset
uspto-grants-1985_01
Patent number
US04495104

Reaction notes

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