一步催化剂转移宏循环:扩大阿扎帕拉cyclophanes的化学空间
Josue Ayuso-Carrillo1, Federica Fina1, El Czar Galleposo1
1Institute of Organic Chemistry, University of Vienna, Währinger Strasse 38, Vienna A-1090, Austria.
Journal of the American Chemical Society
|June 7, 2024
概括
一种新型的一步催化剂转移宏循环反应有效合成多种aza[1]paracyclophanes. 这种多功能方法在温和条件下运行,为创建化学库提供了出色的产量和可扩展性.
科学领域:
- 有机化学
- 催化剂
- 超分子化学
背景情况:
- 传统的宏循环化方法通常需要高稀释,限制可扩展性和效率.
- 亚萨[1]环环 (APC) 是重要的循环结构,具有多样化的应用.
- 开发高效可扩展的合成路线仍然是一个挑战.
研究的目的:
- 报告一种新型的一步催化剂转移宏循环化 (CTM) 反应,用于合成aza[1] paracyclophanes (APCs).
- 展示CTM反应的多功能性和效率,以创建功能化的循环结构.
- 研究影响APC合成产品分布的机制和因素.
主要方法:
- 使用催化布赫瓦尔德-哈特维格交叉合反应进行催化剂转移宏循环 (CTM).
- 使用温和的反应温度 (40°C) 和短的反应时间 (∼2小时).
- 研究了不同内循环和外循环替代剂的结构见解和产品分布.
主要成果:
- 实现了循环结构的选择性合成,包括APC,具有优异的隔离产量 (> 75%).
- 在非高稀释度 (35-350 mM) 下,已被证明有效的宏循环化,最高可形成30%的6个分子旋.
- 确定内循环替代剂影响产品分布 (基类产生6个成员,基/基有利于4个成员的物种),而外循环组的影响最小.
结论:
- 该CTM反应为合成多种APC提供了多功能和高效的平台.
- 反应表现出"活"的行为,使得序列合成和化学图书馆生成的潜力.
- 该CTM过程显示了可扩展性的潜力,克服了传统高稀释宏循环方法的局限性.
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