Ethyl 2- methyl-4-oxocyclohex-2-enecarboxylate (Hagemann's ester) as a precursor to alkyl-substituted 3-methylcyclohexenones
作者:Bruce A. McAndrew
DOI:10.1039/p19790001837
日期:——
from ethyl 2-methyl-4-oxocyclohex-2-enecarboxylate (Hagemann's ester)via the alkylation of its ethylene glycol acetal. Various routes to 6-alkyl-3-methylcyclohex-2-enones from Hagemann's ester have been explored; a particularly convenient route to these unsaturated ketones utilised the isomeric keto-ester, ethyl 4-methyl-2-oxocyclohex-3-enecarboxylate as starting material. The alkylation of ethyl 2-
由2-甲基-4-氧代环己基-2-烯基羧酸乙酯(哈格曼酯)经以下步骤制备4-烷基-3-甲基环己基-2-烯酮乙二醇缩醛的烷基化。已经探索了从哈格曼酯制得6-烷基-3-甲基环己-2-烯酮的各种途径。制备这些不饱和酮的一种特别方便的途径是使用异构的酮酯,4-甲基-2-氧代环己基-3-烯丙基羧酸乙酯作为起始原料。2-甲基-4-吡咯烷基环己-1,3-二烯羧酸乙酯(衍生自哈格曼酯的完全共轭二烯胺)的烷基化反应在水解和脱乙氧基羰基化后生成2-烷基-3-甲基环己-2-烯酮。据报道,哈格曼酯的制备方法有所改进。4-烷基-和6-烷基-3-甲基环己-2-烯酮的制备补充了现有方法,以2-烷基-和5-烷基-3-甲基环己-2-烯酮。