Thionyl Chloride → 7-Methoxy-1,2-dihydro-3-naphthoyl chloride

HRID 1638774Notes

Reaction equation

HRID 1638774 reaction equation
[CH3:1][O:2][C:3]1[CH:12]=[C:11]2[C:6]([CH:7]=[C:8]([C:13]([OH:15])=O)[CH2:9][CH2:10]2)=[CH:5][CH:4]=1.S(Cl)([Cl:18])=O>C1C=CC=CC=1>[CH3:1][O:2][C:3]1[CH:12]=[C:11]2[C:6]([CH:7]=[C:8]([C:13]([Cl:18])=[O:15])[CH2:9][CH2:10]2)=[CH:5][CH:4]=1

Participants

4

Reactant 2

HCID 24386Thionyl ChlorideHCID 127384776-Methoxy-3,4-dihydronaphthalene-2-carboxylic acid

Product 1

HCID 104211287-Methoxy-1,2-dihydro-3-naphthoyl chloride

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A mixture of 7-methoxy-1,2-dihydro-3-naphthoic acid [Jacques et al., Bull. Soc. Chim. Fr., 512 (1950)] (2 g), benzene (50 ml) and thionyl chloride (2 ml) is heated under reflux for one hour. After distilling off the solvent under reduced pressure, benzene (50 ml) is added and the benzene is distilled off again under reduced pressure. The 7-methoxy-1,2-dihydro-3-naphthoyl chloride thus obtained is dissolved in dioxane (10 ml). The solution is added dropwise to a mixture of 1-(3,4,5-trimethoxybenzyl)piperazine dihydrochloride (2.6 g), dioxane (50 ml) and triethylamine (5 ml) at room temperature with stirring. Then the mixture is stirred at room temperature for 30 minutes. Water (300 ml) is added to the mixture, which is extracted with ethyl acetate. The extract solution is washed with a dilute aqueous solution of sodium hydroxide and water, then the solvent is distilled off under reduced pressure. The resulting oily substance is purified by silica gel column chromatography (hexane:acetone=1:1). The product thus obtained is dissolved in ethanol and the solution is treated with on ethanolic hydrogen chloride (5 ml) to give 1-(7-methoxy-1,2-dihydro-3-naphthoyl)-4-(3,4,5-trimethoxybenzyl)piperazine hydrochloride (2.9 g) as colorless crystals, m.p. 210°-215° C. (decomp.).

Workup

  1. temperatureis heated
  2. temperatureunder reflux for one hour
  3. distillationAfter distilling off the solvent under reduced pressure, benzene (50 ml)
  4. additionis added
  5. distillationthe benzene is distilled off again under reduced pressure

Sources & evidence

ORD record
ord-89302cbc093e4af4b32576d7779503c0
Source dataset
uspto-grants-1989_11
Patent number
US04880809

Reaction notes

Loading…