2,5,7,7-Tetramethyloct-2-enal → 2,5,7,7-Tetramethyloctanal

HRID 845372Notes

Reaction equation

HRID 845372 reaction equation
[CH3:1][C:2](=[CH:5][CH2:6][CH:7]([CH3:13])[CH2:8][C:9]([CH3:12])([CH3:11])[CH3:10])[CH:3]=[O:4].[H][H]>CO.[Pd]>[CH3:1][CH:2]([CH2:5][CH2:6][CH:7]([CH3:13])[CH2:8][C:9]([CH3:10])([CH3:12])[CH3:11])[CH:3]=[O:4]

Participants

5

Reactant 2

HCID 539973842,5,7,7-Tetramethyloct-2-enalHCID 178418361HCID 178418361, compound

Product 1

HCID 199810432,5,7,7-TetramethyloctanalYield 97.1%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

In a hydrogenation autoclave, 250 g (1.37 moles) of 2,5,7,7-tetramethyl-2-octenal, dissolved in 500 ml of methanol, were hydrogenated in the presence of 25 g of a 0.5% strength palladium/alumina catalyst at 80° C., initially under a hydrogen pressure of 25 bar, and after 2-3 h, under 55 bar. The total hydrogenation time was 10 h. The catalyst was filtered off, after which fractional distillation gave 245 g (1.33 moles) of 2,5,7,7-tetramethyloctanal (bp.=68° C./0.3 mbar; nD25 =1.4308), corresponding to a yield of 96% of theory. The compound was in the form of a diastereomeric mixture.

Workup

  1. waitThe total hydrogenation time was 10 h
  2. filtrationThe catalyst was filtered off
  3. distillationafter which fractional distillation

Sources & evidence

ORD record
ord-bf9c462445ed4567bf66e6ac104a6224
Source dataset
uspto-grants-1988_07
Patent number
US04758548

Reaction notes

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