A green chemistry-based highly regioselective synthesis of ethyl (9-anthryl)glyoxylate was achieved by solvent-free Friedel-Crafts reaction at r. t. Several derivatives of ethyl (9-anthryl)glyoxylate were also synthesized. Ethyl (9-anthryl)hydroxyacetate was obtained almost quantitatively by reduction of ethyl (9-anthryl)glyoxylate with NaBH4, and (9-anthryl)methoxyacetic acid was prepared by methylation of ethyl (9-anthryl)hydroxyacetate with CH3I in the presence of Ag2O and hydrolysis of ethyl (9-anthryl)methoxyacetate. The hydrolysis of ethyl (9-anthryl)hydroxyacetate gave racemic (9-anthryl)hydroxyacetic acid, and the racemate was successfully resolved by crystallization of the diastereomeric salts resulting from the reaction of (±)-(9-anthryl)hydroxyacetic acid with (-)-ephedrine. As a byproduct, crystals containing racemic (±)-(9-anthryl)hydroxyacetate and protonated (-)-ephedrine were isolated and their structures determined by X-ray diffraction.
通过无溶剂的费托合成反应在室温下实现了对
乙酸乙酯(9-
蒽基)甘酸酯的高度区域选择性绿色合成。还合成了几种
乙酸乙酯(9-
蒽基)甘酸酯的衍
生物。通过NaBH
4还原
乙酸乙酯(9-
蒽基)甘酸酯可以几乎定量地得到
乙酸乙酯(9-
蒽基)
羟基乙酸酯,通过在Ag
2O存在下甲基化
乙酸乙酯(9-
蒽基)
羟基乙酸酯并
水解可以得到(9-
蒽基)
甲氧基乙酸酸。对
乙酸乙酯(9-
蒽基)
羟基乙酸酯的
水解得到了外消旋的(9-
蒽基)
羟基乙酸,而该外消旋体成功通过(-)-
麻黄碱的反应生成二对映异构体盐的结晶分离得到。作为副产物,还分离出含有外消旋的(±)-(9-
蒽基)
羟基乙酸酯和质子化的(-)-
麻黄碱的晶体,并通过X射线衍射确定了它们的结构。