从2-Propargyloxyarylaldehydes衍生出的Eyne体的催化循环异构-氧化循环反应序列
Karmdeo Prajapati1, Manoj Kumar Saini1, Rajesh G Gonnade2
1Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
Organic letters
|November 7, 2024
概括
研究人员使用(III) 三酸盐和DDQ开发了一种单合成2-oxopyranochromenes. 这些化合物可以通过脱碳化氨基化进一步转化为功能化,为有价值的异环化合物提供了一条多功能途径.
科学领域:
- 有机化学 有机化学
- 异环化学 异环化学
背景情况:
- 皮拉诺克罗门是重要的异环基架,具有多样化的生物活动.
- 替代色胺的高效合成方法对于药物化学和材料科学至关重要.
研究的目的:
- 开发一种新的,高效的单合成路径,以获得4 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 乙烯基替代的2 - - - - - - - - - - - - - - - - 氧化.
- 通过脱碳化和氨化探索这些2-oxopyranochromenes的后续功能化.
主要方法:
- 一个两步,一的反应序列,涉及(III) 三甲酸盐催化循环异构,随后是DDQ介导的氧化循环.
- 使用Krapcho条件进行选择性脱碳化.
- 在DMF中,脱碳氧化氨基化与亚利法二次氨基.
主要成果:
- 这种合成成功地产生了各种4 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 乙烯基替代的2 - - - - - - - - - - 氧皮拉诺克罗,产量为32-79%.
- 反应序列显示了广泛的基质范围和良好的功能组耐受性.
- 2-Oxopyranochromenes被有效地转化为2-amino-substituted功能化chromenes通过脱碳化氨基化.
结论:
- 已经建立了一个强大的和多功能的一合成2-oxopyranochromenes的方法.
- 开发的方法提供了通过随后的脱碳化氨基化来获得有价值的功能化.
- 这种方法为产生各种异环化合物的简化途径提供了进一步的应用.
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