3,4-Dimethyl-cyclohex-3-enecarboxylic acid → Methanone, bis(3,4-dimethylphenyl)-

HRID 2414201Notes

Reaction equation

HRID 2414201 reaction equation
[CH3:1][C:2]1[CH2:3][CH:4]([C:9]([OH:11])=O)[CH2:5][CH2:6][C:7]=1[CH3:8]>[Pt]>[CH3:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:6][C:7]=1[CH3:8])[C:9]([C:4]1[CH:5]=[CH:6][C:7]([CH3:8])=[C:2]([CH3:1])[CH:3]=1)=[O:11]

Participants

3

Reactant 1

HCID 114578033,4-Dimethyl-cyclohex-3-enecarboxylic acid

Product 1

HCID 78393Methanone, bis(3,4-dimethylphenyl)-Yield 60%

Reagents, catalysts & solvents 1

HCID 23939PlatinumCatalyst

Procedure

A more complete dehydrogenation of a crude product mixture of the ketonic decarboxylative coupling of 3,4-dimethyl-3-cyclohexene carboxylic acid was accomplished by passing the crude product mixture over a 0.5 wt % platinum on alumina catalyst at a temperature of 385° C. This resulted in a 60 to 75% yield of 3,3',4,4'-tetramethylbenzophenone. The 3,4-dimethyl-3-cyclohexene carboxylic acid had been contacted with a 19 wt % MnO2 /Al2O3 catalyst at a temperature of about 360° C. and a pressure of about 15 psia for a contact time of about 7 sec.

Workup

  1. customat a temperature of 385° C

Sources & evidence

ORD record
ord-63b68b62b611433a8a74fd2568919cb4
Source dataset
uspto-grants-1988_01
Patent number
US04721815

Reaction notes

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