Methanol → 3,7-Dimethyl-2,7-octadienoic acid

HRID 444418Notes

Reaction equation

HRID 444418 reaction equation
C[Li].[CH3:3]N(C)CCN(C)C.[CH3:11][C:12](=[CH2:21])[CH2:13][CH2:14][CH2:15][C:16]#[C:17][C:18]([OH:20])=[O:19].CO>C(OCC)C.CCCCCC>[CH3:3][C:16]([CH2:15][CH2:14][CH2:13][C:12]([CH3:11])=[CH2:21])=[CH:17][C:18]([OH:20])=[O:19]

Participants

7

Reactant 4

HCID 887MethanolHCID 8037N,N,N',N'-TetramethylethylenediamineHCID 128775997-Methyl-7-octen-2-ynoic acidHCID 178418348HCID 178418348, compound

Product 1

HCID 540284963,7-Dimethyl-2,7-octadienoic acid

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolvent2×HCID 8058HexaneSolvent

Procedure

To 11.0 mmol of cuprous iodide in 30 ml of dry diethyl ether at -40° under nitrogen is added 10.6 mmol of methyllithium in hexane, followed immediately by 13.0 mmol of tetramethylethylenediamine (TMEDA). After stirring for 30 min, the suspension is cooled to about -50°, and 10 mmol of the methyl ester of 7-methyl-7-octen-2-ynoic acid in 1 ml ether is added dropwise. The temperature is maintained at -45° to -50° for 20 min and then 2 ml of methanol is added dropwise to quench the reaction, followed by 1 ml sat. (NH4)2SO4. The suspension is allowed to warm to RT, after which the solid is filtered off and washed with ether. The combined organic layers are washed with sat. (NH4)2SO4, 5% HCl, sat. NaHCO3 and brine, then dried over CaSO4. The solvent is removed by distillation, yielding the Z methyl ester of 3,7-dimethyl-2,7-octadienoic acid.

Workup

  1. temperaturethe suspension is cooled to about -50°
  2. temperatureThe temperature is maintained at -45° to -50° for 20 min
  3. customto quench
  4. customthe reaction
  5. filtrationafter which the solid is filtered off
  6. washwashed with ether
  7. washThe combined organic layers are washed with sat. (NH4)2SO4, 5% HCl, sat. NaHCO3 and brine
  8. dry with materialdried over CaSO4
  9. customThe solvent is removed by distillation

Sources & evidence

ORD record
ord-a8b6f74ac88649af86ff519a5461bcd4
Source dataset
uspto-grants-1981_04
Patent number
US04264518

Reaction notes

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