Conversion of (±)-3-ethyl-3-methyl phthalides to 3,3-dimethyl-3,4-dihydroisocoumarins. Synthesis of 3-methylmellein
作者:B. H. Bhide、A. J. Kalaria、B. M. Panchal
DOI:10.1002/jhet.5570390403
日期:2002.7
o-Lithio yV-methyl benzamides (1a-f) upon alkylation with ethyl methyl ketone gave (±)-3-ethyl-3-methylphthalides (2a-f), which upon treatment with concentrated H2SO4 or anhydrous A1C13 furnished corresponding 3,3-dimethyl-3,4-dihydroisocoumarins (3a-f) and 3-methyl mellein (3g).
与乙基甲基酮烷基化后,邻-硫代γ-甲基苯甲酰胺(1a-f)得到(±)-3-乙基-3-甲基邻苯二甲酸酯(2a-f),经浓H 2 SO 4或无水AlCl 3处理提供了相应的3,3-二甲基-3,4-二氢异香豆素(3a-f)和3-甲基蜜莱因(3g)。