Ethylene Glycol → 4-Amino-4-phenylcyclohexan-1-one

HRID 1462508Notes

Reaction equation

HRID 1462508 reaction equation
C1O[C:4]2([CH2:9][CH2:8][C:7]([N:16]=C=O)([C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=3)[CH2:6][CH2:5]2)[O:3]C1.[OH-].[Na+].C(O)CO.Cl>C(OCC)C.O>[NH2:16][C:7]1([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH2:6][CH2:5][C:4](=[O:3])[CH2:9][CH2:8]1

Participants

7

Reactant 4

HCID 174Ethylene GlycolHCID 313Hydrochloric Acid2×HCID 14798Sodium Hydroxide2×HCID 125955658-Isocyanato-8-phenyl-1,4-dioxaspiro[4.5]decane

Product 1

HCID 204533024-Amino-4-phenylcyclohexan-1-oneYield 52%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent2×

Procedure

A reaction mixture consisting of 21.9 gm. (0.085 mole) 4-isocyanato-4-phenylcyclohexanone ethylene ketal (prepared as in Example 17, Part G), 10.9 gm. sodium hydroxide, and 210 ml. ethylene glycol is heated at the reflux temperature for sixty-six (66) hours. A solution results which is cooled in an ice-water bath. A small amount of ice is added to the solution followed by 23 ml. of concentrated hydrochloric acid which is added dropwise with stirring. After five minutes, the acidified solution is made strongly basic by adding 50% aqueous sodium hydroxide. The basic solution is diluted with 800 ml. water. The strongly basic, dilute aqueous solution is then extracted four times with 200 ml. portions of diethyl ether. The extracts are combined and washed with water and with brine, before removing the ether by evaporation under reduced pressure. The residue thus obtained is dissolved in 50 ml. of diethyl ether and the oily solution is treated with an equivalent of 3 N hydrogen chloride in diethyl ether. A precipitate forms which is collected on a filter and recrystallized from a mixture of methylene chloride and ethyl acetate. There is thus obtained 15.2 gm. (52% yield) of 4-amino-4-phenylcyclohexanone, ethylene ketal hydrochloride which has a melting point at 226° to 228° C. (with decomposition). A second crop of crystals weighs 1.60 gm. and has a melting range from 222° to 226° C. An analytical sample has a melting point at 248° to 249° C.

Workup

  1. customA solution results which
  2. temperatureis cooled in an ice-water bath
  3. additionA small amount of ice is added to the solution
  4. additionThe basic solution is diluted with 800 ml
  5. extractionThe strongly basic, dilute aqueous solution is then extracted four times with 200 ml
  6. washwashed with water and with brine
  7. custombefore removing the ether
  8. customby evaporation under reduced pressure
  9. customThe residue thus obtained
  10. dissolutionis dissolved in 50 ml
  11. customA precipitate forms which is collected on
  12. filtrationa filter
  13. customrecrystallized from a mixture of methylene chloride and ethyl acetate

Sources & evidence

ORD record
ord-d33e8dbebe8b440b8f9d8accbdd726e6
Source dataset
uspto-grants-1984_07
Patent number
US04460604

Reaction notes

Loading…