Diethyl Ether → (E)-6,6-dimethyl-2-hepten-4-ynylmalonic acid dimethyl ester

HRID 1757269Notes

Reaction equation

HRID 1757269 reaction equation
[CH3:1][O:2][C:3](=[O:9])[CH2:4][C:5]([O:7][CH3:8])=[O:6].[H-].[Na+].[CH3:12][C:13]([CH3:21])([CH3:20])[C:14]#[C:15]/[CH:16]=[CH:17]/[CH2:18]Br.C(OCC)C>CN(C)C=O>[CH3:1][O:2][C:3](=[O:9])[CH:4](/[CH:18]=[CH:17]/[CH2:16][C:15]#[C:14][C:13]([CH3:21])([CH3:20])[CH3:12])[C:5]([O:7][CH3:8])=[O:6]

Participants

6

Reactant 4

HCID 3283Diethyl Ether2×HCID 7943Dimethyl malonateHCID 24758Sodium hydrideHCID 110744282-Hepten-4-yne, 1-bromo-6,6-dimethyl-

Product 1

HCID 86748936(E)-6,6-dimethyl-2-hepten-4-ynylmalonic acid dimethyl ester

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

4.05 ml of malonic acid dimethyl ester is dissolved in 40 ml of dimethylformamide, 1.29 g of 60% oily sodium hydride and 6.5 g of (E)-6,6-dimethyl-2-hepten-4-ynyl bromide (containing about 5% Z-form) are added gradually, and the mixture is stirred at that temperature for 1 hour. Saturated saline and ethyl ether are added to the reaction solution to form two liquid phases, the ether layer is taken, washed with saturated saline and dried over anhydrous magnesium sulfate, and the solvent is distilled off under reduced pressure. The residue is purified by silica gel column chromatography [Wako gel C-200, 400 g; hexane/ethyl acetate=19/1→9/1] to obtain 6.26 g of (E)-6,6-dimethyl-2-hepten-4-ynylmalonic acid dimethyl ester as colorless oil.

Workup

  1. customto form two liquid phases
  2. washwashed with saturated saline
  3. dry with materialdried over anhydrous magnesium sulfate
  4. distillationthe solvent is distilled off under reduced pressure
  5. customThe residue is purified by silica gel column chromatography [Wako gel C-200, 400 g; hexane/ethyl acetate=19/1→9/1]

Sources & evidence

ORD record
ord-648a66d1ab09436ca6a3a64fbe9155d8
Source dataset
uspto-grants-1995_08
Patent number
US05444084

Reaction notes

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