Potassium Hydroxide → 2-Methylhexahydroisoquinoline-6,8(2H,7H)-dione

HRID 2413027Notes

Reaction equation

HRID 2413027 reaction equation
[Na].C([C:4](CC)(C([O-])=O)[C:5]([O-])=[O:6])C.[CH3:13][N:14]1[CH2:19][CH2:18][CH:17]=[C:16]([C:20](=[O:22])[CH3:21])[CH2:15]1.[OH-].[K+]>C(O)C.O>[CH3:13][N:14]1[CH2:19][CH2:18][CH:17]2[CH:16]([C:20](=[O:22])[CH2:21][C:5](=[O:6])[CH2:4]2)[CH2:15]1

Participants

7

Reactant 4

HCID 14797Potassium HydroxideHCID 5360545Sodium2×HCID 69515632,2-DiethylpropanedioateHCID 10975568HCID 10975568, compound

Product 1

HCID 128559332-Methylhexahydroisoquinoline-6,8(2H,7H)-dione

Reagents, catalysts & solvents 2

HCID 702EthanolSolvent3×HCID 962WaterSolvent

Procedure

A 250 ml three necked flask, equipped with magnetic stirrer, reflux condenser and nitrogen inlet was charged with 80 ml ethanol. Thereafter, 2.28 g of sodium metal, freshly cut, was added and the mixture stirred till all the sodium had dissolved. Then, 12.33 g of diethylmalonate in 6 ml of ethanol, and 9.74 g of 1-(1,2,5,6-tetrahydro-1-methyl-3-pyridinyl)ethanone (arecolone) in 6 ml of ethanol, were added to the warm solution and the resulting solution was stirred and heated to reflux for 5 hours. Then, 10.2 g of 85% potassium hydroxide pellets were added and the mixture heated to reflux for four hours. During this period a heavy precipitate formed. With the aid of 50 ml water, the mixture was transferred into a 500 ml flask and concentrated at 30° and 20 mm of pressure. The residue was again concentrated from 50 ml water. It was then taken up in 100 ml water. 45 ml 12N hydrochloric acid were added and the solution was heated to reflux for 2 hours. It was then cooled and concentrated on a rotovap at 40° and 20 mm of pressure.

Workup

  1. temperaturereflux condenser and nitrogen inlet
  2. additionwas added
  3. dissolutionhad dissolved
  4. temperatureheated
  5. temperatureto reflux for 5 hours
  6. temperaturethe mixture heated
  7. temperatureto reflux for four hours
  8. customDuring this period a heavy precipitate formed
  9. concentrationconcentrated at 30°
  10. concentrationThe residue was again concentrated from 50 ml water
  11. addition45 ml 12N hydrochloric acid were added
  12. temperaturethe solution was heated
  13. temperatureto reflux for 2 hours
  14. temperatureIt was then cooled
  15. concentrationconcentrated on a rotovap at 40°

Sources & evidence

ORD record
ord-2954f6b458c04fe494fcc21faa113a70
Source dataset
uspto-grants-1985_01
Patent number
US04495354

Reaction notes

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