Ethyl isodehydroacetate

Ethylenimine, 30, 38 toxic properties of, 30, 40 Ethyl o-ethoxybenzoate, 32, 75 Ethyl formate, 32, 32 Ethyl glycidyl ether, 31, 3 2-Ethylhexanaldoxime, 32, 67 2-Ethylhexanamide, 32, 65 2-Ethylhexanoic acid, 32, 66 2-Ethylhexanonitrile, 32, 65 Ethylidene bromide, 32, 55 Ethyl iodide, 31, 34 Ethyl isodehydroacetate, 32, 76 Ethyl lactate, 31, 59, 60 5-ETHYL-2-METHYLPYRIDINE, 30, 41 Ethyl orthocarbonate, 32, 68 Ethyl orthoformate, 32, 5 Ethyl orthosilicate, 32, 5 Ethyl phenylazoacetoacetate, 32, 85 Ethyl phenylcyanoacetate, 30,43,80 Ethyl 0-phenyl-/3-cyanopropionate, 30, 84... 

The ether extract, which contains ethyl isodehydroacetate, is dried for 24 hours over anhydrous sodium sulfate, and the ether is then removed by heating on a water bath. The residue is distilled from a 250-ml. Claisen flask, under reduced pressure, to give 130-175 g. (27-36%) of ethyl isodehydroacetate b.p. 185-192°/35 mm. m.p. 18-20° (Notes 6 and 7). 

The fore-run of 30-40 g consists mostly of a mixture of 4,6-dimethyl-l,2-pyrone and ethyl isodehydroacetate. 

LAH attacks pyran-2-ones, such as (303), at C-6, opens the ring and forms 3-methylhexa-2,4-dienoic (3-methylsorbic) acid (302). Sodium borohydride is more selective and is the reagent of choice for reducing ethyl isodehydroacetate (303 R = C02Et) to give, after alkali hydrolysis of the ester, the dicarboxylic acid (304) <62CI(L)268). 

Ethyl isocyamde, 35, 62 Ethyl isodehydroacetate, 32, 76 Ethyl lactate, 31, 59, 60 Ethylmagnesium bromide, 36, 87 Ethyl mandelate, 36, 3 Ethyl N-methylcarbamate, 35, 94 /S-ElHYL-iS-METHYLGLUTARIC ACID, 36, 28... 

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