在连续流中对N-Boc受保护氨基进行选择性热去保护
Michelle-Rose Ryan1, Denis Lynch1, Stuart G Collins2
1School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork, Cork T12 YN60, Ireland.
概括
这项研究证明了在连续流中氨基的高效,无催化剂的热N-Boc降解保护. 通过温度控制实现了选择性降低保护,使不同N-Boc组的顺序去除成为可能.
科学领域:
- 有机化学 有机化学
- 过程化学 过程化学
- 合成方法论 合成方法论
背景情况:
- tert-butoxycarbonyl (N-Boc) 保护组在有机合成中被广泛使用.
- 传统的N-Boc脱保护通常需要恶劣的酸性条件,限制其在复杂分子合成中的应用.
- 连续流化学在反应控制,安全和可扩展性方面具有优势.
研究的目的:
- 开发一种新的,无酸的方法,用于热N-Boc脱保护.
- 调查在连续流系统中执行N-Boc去保护的可行性.
- 通过温度控制来证明不同N-Boc组的选择性降低保护.
主要方法:
- 在连续流反应堆中进行了各种氨基的热N-Boc脱保护.
- 用不同的溶剂进行反应,包括甲醇和三乙醇,以评估溶剂的影响.
- 温度被精确控制,以实现对基N-Boc组与基N-Boc组的选择性去保护.
主要成果:
- 在连续流中的一系列氨基酸中实现了高效且无催化剂的热N-Boc降解保护.
- 在甲醇和三乙醇中获得最佳结果,但该方法在各种极性中证明有效.
- 顺序选择性降解保护被成功证明,在基N-Boc组之前先去除一个基N-Boc组.
结论:
- 连续流热N-Boc去保护为传统方法提供了温和而高效的替代方案.
- 温度控制是实现差异保护氨基的选择性降解保护的关键参数.
- 开发的方法适用于望远镜合成序列,如胺13的成功合成所示.
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