Treatment of 2-bromomethyl cycloheptanone (3) with acetoacetic ester in the presence of sodium ethoxide furnished ethyl1-methylcyclohexyl carbonylacetate (6) in 35% yield. A mechanism leading to the formation of thej3-ketoester (6) m Favorskii rearrangement involving nucleophilic attack of a carbanion (sodio-acetoacetic ester) on the cyclopropanone intermediate (4) is suggested.3-Methyl cyclohexanone and 2,4-dimethyl cyclohexanone (8 and 8a) were transformed into enamines (9 and 9a), which were further acylated with ethyl chloroformate by Stork's et al method [11]. Reduction of enamine (10) by lithium aluminum hydride afforded the syrup 3,5dimethyl-1-cyclohexenyl-1-carboxaldehyde (12) in 15% yield and 3,5-dimethyl-1-cyclohexenyl-1carbinol (13) in 23% yield. Similarly, the product (11) on reduction followed by column chromatography afforded three derivatives (14), (15) and (16) in low yield.
M Y KHAN ,A U REHMAN ,
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