Hydrochloric Acid → 6-Hydroxy-2,5,7,8-tetramethylchroman-2-acetic acid

HRID 1706619Notes

Reaction equation

HRID 1706619 reaction equation
C([O:4][C:5]1[C:6]([CH3:21])=[C:7]([CH3:20])[C:8]2[O:13][C:12]([CH3:17])([CH2:14][C:15]#N)[CH2:11][CH2:10][C:9]=2[C:18]=1[CH3:19])(=O)C.[OH-:22].[K+].Cl.[OH2:25]>C(O)CO>[OH:4][C:5]1[C:6]([CH3:21])=[C:7]([CH3:20])[C:8]2[O:13][C:12]([CH2:14][C:15]([OH:25])=[O:22])([CH3:17])[CH2:11][CH2:10][C:9]=2[C:18]=1[CH3:19]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 962Water2×HCID 14797Potassium HydroxideHCID 57234417rac.-6-acetyloxy-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrile

Product 1

HCID 55926-Hydroxy-2,5,7,8-tetramethylchroman-2-acetic acidYield 82%

Reagents, catalysts & solvents 1

HCID 174Ethylene GlycolSolvent

Procedure

A mixture of 1.0 g (3.48 mmoles) of rac.-6-acetyloxy-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrile, 1.0 g (15.2 mmoles) of 85% KOH, 1 ml of water and 8 ml of ethylene glycol was stirred and refluxed for 16 hr. The reaction mixture was cooled to room temperature, then poured into water. The pH of the solution was adjusted to 8 with 1 N aqueous HCl. The resulting mixture was extracted with two portions of ether (the ether extracts were discarded). The aqueous phase was acidified with 3 N aqueous HCl and worked-up with ether in the usual manner giving 756 mg (82%) of rac.-(6-hydroxy-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-yl)acetic acid as a tan solid.

Workup

  1. temperaturerefluxed for 16 hr
  2. extractionThe resulting mixture was extracted with two portions of ether (the ether extracts

Sources & evidence

ORD record
ord-e190bbc75d964768aa20c4093edd078f
Source dataset
uspto-grants-1980_06
Patent number
US04208333

Reaction notes

Loading…