Isoprene → 1-(2,2,4-Trimethyl-3-cyclohexen-1-yl)ethan-1-one

HRID 2058989

Reaction equation

HRID 2058989 reaction equation
[O:1]=[C:2]([CH:4]=[C:5]([CH3:7])[CH3:6])[CH3:3].[Cl-].[Al+3].[Cl-].[Cl-].[CH2:12]=[CH:13][C:14](=C)[CH3:15].[C:17]1(C)CCC(C(C)=C)CC=1>C1(C)C=CC=CC=1>[C:2]([CH:4]1[CH2:15][CH2:14][C:13]([CH3:12])=[CH:6][C:5]1([CH3:17])[CH3:7])(=[O:1])[CH3:3]

Participants

6

Reactant 4

HCID 6557IsopreneHCID 8858Mesityl oxideHCID 223111-Methyl-4-Prop-1-En-2-YlcyclohexeneHCID 6451240Aluminum(III) Chloride

Product 1

HCID 30169881-(2,2,4-Trimethyl-3-cyclohexen-1-yl)ethan-1-one

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent2×

Procedure

Mesityl oxide (441 g) is added at 12°-16° C. to a stirred suspension of aluminum chloride (63 g) in toluene (2100 ml). A solution of isoprene (1224 g) in toluene (1800 ml) is then added over a period of 1.5 hr. at 15°-20° C. After approximately 48 hr. at 15°-25° C., the reaction mixture is washed successively with 10% hydrochloric acid sollution, water, 10% sodium bicarbonate solution, and water. The washed material is distilled rapidly at 3 mm Hg using a short column to give 626 g of crude product. Fractionation of 548 g of this material through a 12"×1", Goodloe packed column gives 478 g of 4-acetyl-1,3,3-trimethyl-1-cyclohexene containing a small amount of 1,8-p-menthadiene. The structure is confirmed by NMR (1H and 13C).

Workup

  1. customat 15°-20° C
  2. washat 15°-25° C., the reaction mixture is washed successively with 10% hydrochloric acid sollution, water, 10% sodium bicarbonate solution, and water
  3. distillationThe washed material is distilled rapidly at 3 mm Hg
  4. customto give 626 g of crude product

Sources & evidence

ORD record
ord-612fbb855d0a4cc3a66f8000a93e5deb
Source dataset
uspto-grants-1982_03
Patent number
US04320771

Linked notes

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