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通过结和分散相互作用实现的同质氨基的催化多元组分合成

Elisabetta Ronchi¹, Shauna M Paradine¹, Eric N Jacobsen¹

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|May 5, 2021

概括

这项研究引入了一种新的单步方法,用于从乙烯酸中使用硫尿素催化剂制造性同质性N-Boc氨基. 该过程通过选择性地捕捉离子与基来有效地产生聚丰富胺.

科学领域:

有机化学
催化剂
不对称的合成

背景情况:

胺是药物和天然产品的重要组成部分.
开发高效和选择性合成方法对于获取这些化合物至关重要.
从易于获得的起始材料,如乙,直接合成仍然是一个挑战.

研究的目的:

开发一种用于合成同质性N-Boc氨基的新型一阶段催化酶选择方法.
为了利用乙烯酸作为前体,用于离子生成和随后的化.
研究这种催化转化中的立体差异化机制.

主要方法:

一个单步反应,结合了乙,性硫尿素催化剂,试基三酸盐和N-Boc碳酸盐.
在现场生成反应性离子中间体.
离子被素核友捕获.
对产品的反体过量 (ee) 的分析.
计算研究以阐明过渡状态和非共价相互作用.

主要成果:

成功地从高反缩的乙直接制备同质性N-Boc氨基.
证明了对离子合的高选择性,而不是氧碳离子合,避免了以太的副产品.
展示了该方法对一系列具有不同功能组的芳香性化物的适用性.
在立体决定过渡状态中确定了催化剂的pyrenyl部分和基质之间的关键 π-stacking非共价相互作用 (NCI).

结论:

开发的方法提供了一种高效和对乙烯酸有价值的同质胺的选择性途径.
反应机制涉及特定的结和π堆叠相互作用用于立体控制.
这种方法提供了先前报告的方法的替代方案,突出了不对称催化剂的不同非对应相互作用模式.

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