[C:1]([CH2:3][C:4]([O:6][CH3:7])=[O:5])#[N:2].[CH3:8][CH:9]([C:11](=O)[CH2:12][CH2:13][CH3:14])[CH3:10].C([O-])(=O)C.[NH4+].C(O)(=O)C>C1(C)C=CC=CC=1.C(OCC)(=O)C.O>[C:1]([C:3](=[C:11]([CH2:12][CH2:13][CH3:14])[CH:9]([CH3:10])[CH3:8])[C:4]([O:6][CH3:7])=[O:5])#[N:2]A mixture of methyl cyanoacetate (1.98 g), 2-methylhexan-3-one (3.76 g), ammonium acetate (0.196 g) and glacial acetic acid (0.288 ml) in toluene (10 ml) was stirred and heated at reflux with removal of water using a Dean and Stark apparatus for 6 hours. After cooling to room temperature the mixture was diluted with ethyl acetate and washed with water, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica eluting with a mixture of ethyl acetate and pentane (2%) to give methyl 2-cyano-3-propyl-4-methylpent-2-enoate (as a mixture of E and Z isomers) (2.11 g) as a colourless oil.
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