Hydrochloric Acid → 8,9-dichloro-5-methyl-6,7-dihydro-1-oxo-1H,5H-benzo[ij]quinolizine-2-carboxylic acid

HRID 1649430Notes

Reaction equation

HRID 1649430 reaction equation
[Cl:1][C:2]1[C:11]([Cl:12])=[CH:10][CH:9]=[C:8]2[C:3]=1[CH2:4][CH2:5][CH:6]([CH3:13])[NH:7]2.C([O:16][CH:17]=[C:18]([C:24](OCC)=O)[C:19]([O:21]CC)=[O:20])C.O=P12OP3(OP(OP(O3)(O1)=O)(=O)O2)=O.P(=O)(O)(O)O.[OH-].[Na+].Cl>>[Cl:1][C:2]1[C:3]2=[C:8]3[N:7]([CH:6]([CH3:13])[CH2:5][CH2:4]2)[CH:24]=[C:18]([C:19]([OH:21])=[O:20])[C:17](=[O:16])[C:9]3=[CH:10][C:11]=1[Cl:12]

Participants

7

Reactant 6

HCID 313Hydrochloric AcidHCID 1004Phosphoric AcidHCID 6871Diethyl (ethoxymethylene)malonateHCID 14798Sodium HydroxideHCID 14812Phosphorus oxide (P4O10)HCID 155717775,6-Dichloro-2-methyl-1,2,3,4-tetrahydroquinoline

Product 1

HCID 155717798,9-dichloro-5-methyl-6,7-dihydro-1-oxo-1H,5H-benzo[ij]quinolizine-2-carboxylic acidYield 49.8%

Conditions

Temperature
160 °C

Procedure

A mixture of 3.2 g of 5,6-dichloro-1,2,3,4-tetrahydroquinaldine and 3.2 g of diethyl ethoxymethylenemalonate was allowed to react by heating at 160° C. for 30 minutes. Then 13 g of polyphosphoric acid prepared from 6.5 g of phosphorus pentoxide and 6.5 g of phosphoric acid was added to the mixture and the resulting mixture was allowed to react by heating at 140° to 150° C. for 1 hour. After completion of the reaction, the mixture was poured onto 100 g of ice, followed by rendering the mixture to pH 4 to 5 with a 40% aqueous sodium hydroxide solution to precipitate crystals. The crystals were collected by filtration, dried and mixed with 50 ml of a 10% aqueous sodium hydroxide solution. The mixture was allowed to react at 100° to 110° C. for 1 hour. After cooling, the reaction mixture was rendered acidic with concentrated hydrochloric acid to precipitate crystals. Recrystallization of the crystals thus-obtained from ethanol gave 2.3 g of 8,9-dichloro-5-methyl-6,7-dihydro-1-oxo-1H,5H-benzo[ij]quinolizine-2-carboxylic acid having a melting point of 269° to 271° C.

Workup

  1. customto react
  2. additionwas added to the mixture
  3. customto react
  4. temperatureby heating at 140° to 150° C. for 1 hour
  5. customAfter completion of the reaction
  6. customto precipitate crystals
  7. filtrationThe crystals were collected by filtration
  8. customdried
  9. additionmixed with 50 ml of a 10% aqueous sodium hydroxide solution
  10. customto react at 100° to 110° C. for 1 hour
  11. temperatureAfter cooling
  12. customto precipitate crystals
  13. customRecrystallization of the crystals
  14. customthus-obtained from ethanol

Sources & evidence

ORD record
ord-2ba20b734416438692e59e7f57b5ee40
Source dataset
uspto-grants-1983_11
Patent number
US04416884

Reaction notes

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