Ethyl 2-methyl-3,4-pentadienoate → ethyl (2E)-2-methylpenta-2,4-dienoate
Reaction equation
[O-]CC.[Na+].[CH3:5][CH:6]([CH:12]=[C:13]=[CH2:14])[C:7]([O:9][CH2:10][CH3:11])=[O:8]>C(O)C>[CH3:5]/[C:6](=[CH:12]\[CH:13]=[CH2:14])/[C:7]([O:9][CH2:10][CH3:11])=[O:8]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Sodium ethoxide solution (21% in ethanol, 33.3 ml, cat.) was added to a solution of ethyl 2-methylpenta-3,4-dienoate (Bedoukian, 125.0 g, 890 mmol) in anhydrous ethanol (350 ml) and stirred at ambient temperature for 12 hours. The solution was concentrated in vacuo and the residue partitioned between ether and saturated NH4Cl solution. The aqueous phase was re-extracted twice with ether, then the combined organic phase washed with NH4Cl and then brine, dried over Na2SO4, filtered and the solvents removed in vacuo to yield the crude ester, 125.8 g as an orange oil which was used directly in the next step without further purification.