Hydrochloric Acid → HCID 19736746, compound

HRID 326312Notes

Reaction equation

HRID 326312 reaction equation
C[O:2][C:3]1[CH:17]=[C:16]([O:18][CH3:19])[CH:15]=[C:14]2[C:4]=1[C:5](=[O:20])[CH2:6][C:7]1([NH:13]2)[CH2:12][CH2:11][CH2:10][CH2:9][CH2:8]1.Cl.N1C=CC=CC=1.Cl>>[OH:2][C:3]1[CH:17]=[C:16]([O:18][CH3:19])[CH:15]=[C:14]2[C:4]=1[C:5](=[O:20])[CH2:6][C:7]1([NH:13]2)[CH2:8][CH2:9][CH2:10][CH2:11][CH2:12]1

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 10176127Pyridinium chlorideHCID 19736708HCID 19736708, compound

Product 1

HCID 19736746HCID 19736746, compound

Conditions

Temperature
190 °C

Procedure

A mixture of 5,7-dimethoxyspiro[1,2,3,4-tetrahydroquinoline-2,1'-cyclohexan]-4-one (prepared in Preparation 80) (0.422 g, 1.53 mmol) and pyridine hydrochloride (1.2 g, 10.4 mmol) is heated at 190° C. for one hour with stirring under nitrogen gas. After cooling, dilute hydrochloric acid is added to the mixture and the mixture is extracted with ethyl acetate. The extract is washed with saturated brine, dried, and the solvent is removed by distillation. The residue is placed on a silica gel column and eluted with a mixture of ethyl acetate and dichloromethane (1:3). From the earlier fractions, 5-hydroxy-7-methoxyspiro[1,2,3,4-tetrahydroquinoline-2,1'-cyclohexan]-4-one is obtained as a crystalline solid (0.098 g, 25%). From the succeeding fractions, the title compound is obtained as a crystalline solid (0.26 g, 68%). Recrystallization from diethyl ether gives a product having a melting point of 132°-133° C.

Workup

  1. temperatureAfter cooling
  2. extractionthe mixture is extracted with ethyl acetate
  3. washThe extract is washed with saturated brine
  4. customdried
  5. customthe solvent is removed by distillation
  6. washeluted with a mixture of ethyl acetate and dichloromethane (1:3)

Sources & evidence

ORD record
ord-f00d18be225344afbde5cf757da678b0
Source dataset
uspto-grants-1993_12
Patent number
US05268386

Reaction notes

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