Hydrochloric Acid → 6-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxylic acid

HRID 2243183Notes

Reaction equation

HRID 2243183 reaction equation
C[O:2][C:3]([C:5]1[S:9][C:8]2[CH2:10][CH:11]([CH3:14])[CH2:12][CH2:13][C:7]=2[CH:6]=1)=[O:4].[Li+].[OH-].Cl>C1COCC1.CO>[CH3:14][CH:11]1[CH2:10][C:8]2[S:9][C:5]([C:3]([OH:4])=[O:2])=[CH:6][C:7]=2[CH2:13][CH2:12]1

Participants

6

Reactant 3

HCID 313Hydrochloric AcidHCID 3939Lithium HydroxideHCID 67017790HCID 67017790, compound

Product 1

HCID 38704956-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxylic acidYield 87.4%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 704 mg of 6-methyl-4,5,6,7-tetrahydro-benzo[b]thiophene-2-carboxylic acid methyl ester (obtained in step b) in a mixture of THF (5ml) and methanol (2 ml) were added 8.37 ml of 1N LiOH and the reaction mixture was stirred at RT for 16 h. Then the pH was adjusted to 2 by addition of 2N HCl and the suspension was extracted with ethyl acetate. The combined organic extracts were washed with brine, dried (MgSO4) and concentrated. The remaining residue was then purified by crystallization from hot dichloromethane to give 574 mg (87%) of 6-methyl-4,5,6,7-tetrahydro-benzo[b]thiophene-2-carboxylic acid as brown solid. MS (ISP) 195.1 (M−H)−.

Workup

  1. extractionthe suspension was extracted with ethyl acetate
  2. washThe combined organic extracts were washed with brine
  3. dry with materialdried (MgSO4)
  4. concentrationconcentrated
  5. customThe remaining residue was then purified by crystallization from hot dichloromethane

Sources & evidence

ORD record
ord-34e403b32e194ecbbb46b25cc25449cc
Source dataset
uspto-grants-2010_03
Patent number
US07674815B2

Reaction notes

Loading…