Hydrochloric Acid → 1-Methyl-4,4-diphenylpiperidine

HRID 328245Notes

Reaction equation

HRID 328245 reaction equation
[CH3:1][N:2]1[CH2:7][CH2:6][C:5](O)([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)[CH:4](C(=O)C2C=CC=CC=2)[CH2:3]1.[Cl-].[Al+3].[Cl-].[Cl-].Cl>C1C=CC=CC=1>[CH3:1][N:2]1[CH2:3][CH2:4][C:5]([C:8]2[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=2)([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)[CH2:6][CH2:7]1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 20784(4-Hydroxy-1-methyl-4-phenylpiperidin-3-yl)(phenyl)methanoneHCID 6451240Aluminum(III) Chloride2×

Product 1

HCID 2079801-Methyl-4,4-diphenylpiperidine

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Conditions

Temperature
45 °C

Procedure

100 g. of 1-methyl-3-benzoyl-4-hydroxy-4-phenylpiperidine are suspended in 600 ml. of anhydrous benzene while stirring. 200 g. of finely pulverized, anhydrous aluminum chloride are added in portions thereto within 25 minutes. The reaction temperature increases to about 45° C. when adding the first portion of aluminum chloride. After about 20 minutes the reaction temperature of the reaction mixture is maintained at 50° to 55° C. for about 1 hour. The reaction mixture is then cooled to room temperature and is introduced into a mixture of ice and concentrated hydrochloric acid while stirring. After heating the mixture to room temperature, the benzene layer is separated from the hydrochloric acid and oil layer which is washed with benzene. The hydrochloric acid and oil layer is diluted, while stirring, with an amount of water sufficient to cause substantially all the oil to be dissolved. The resulting aqueous solution is then rendered alkaline by the addition of 40% sodium hydroxide solution, while stirring, and the alkaline solution is extracted with ether. The combined ether extracts are dried over anhydrous potassium carbonate and are concentrated by evaporation of the ether. 83.5 g. of the crude base are obtained as residue in the form of a dark oil. A light oil boiling at 98° to 103° C./0.01 mm. Hg is recovered by distillation of said crude oil in a high vacuum. The oil solidifies to crystals on standing for a short period of time. After recrystallization from aqueous dimethylformamide, the resulting 1-methyl-4,4-diphenylpiperidine has a melting point of 71° to 73° C.

Workup

  1. temperatureAfter about 20 minutes the reaction temperature of the reaction mixture is maintained at 50° to 55° C. for about 1 hour
  2. temperatureThe reaction mixture is then cooled to room temperature
  3. temperatureAfter heating the mixture to room temperature
  4. customthe benzene layer is separated from the hydrochloric acid and oil layer which
  5. washis washed with benzene
  6. additionThe hydrochloric acid and oil layer is diluted
  7. stirringwhile stirring, with an amount of water sufficient
  8. dissolutionto be dissolved
  9. additionby the addition of 40% sodium hydroxide solution
  10. stirringwhile stirring
  11. extractionthe alkaline solution is extracted with ether
  12. dry with materialThe combined ether extracts are dried over anhydrous potassium carbonate
  13. concentrationare concentrated by evaporation of the ether

Sources & evidence

ORD record
ord-d58b11e7b9d2448fbb1c95f12e43a9d3
Source dataset
uspto-grants-1977_04
Patent number
US04016280

Reaction notes

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