We report herein the convergent synthesis of the 7,8,9,10-tetrahydro-9-hydroxy-6,11-dimethoxy-5,12-naphthacenedione (9), an advanced intermediate in the synthesis of (±)-4-demethoxy-daunomycinone, using the aryne dipolar cycloaddition reaction of lithiated 3-cyanophthalide and 2-bromo-5,6-dihydro-1,4-dimethoxynapththalene (6) in the key step. Similarly, the non-convergent synthesis of the 7,8-dihydro-4,6,11-trimethoxy-5,12-naphthacenedione (10), an important intermediate in the synthesis of (±)-daunomycinone, is presented.
我们在此报告7,8,9,10-四氢-9-羟基-6,11-二甲氧基-5,12-
并四苯醌(9)的收敛合成,这是合成(±)-4-去甲氧基
柔红霉素的关键中间体,其关键步骤是利用
锂化3-
氰基
苯酞和2-
溴-5,6-二氢-
1,4-二甲氧基萘(6)的芳基双极环加成反应。同样,我们还介绍了7,8-二氢-4,6,11-
三甲氧基-5,12-
并四苯醌(10)的非收敛合成,这是合成(±)-
柔红霉素的重要中间体。