连接体和离子体参数的系统变化可以通过基质-连接体静电相互作用选择多重化的C-C和C-N交叉合
William A Golding1, Hendrik L Schmitt1, Robert J Phipps1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
Journal of the American Chemical Society
|December 17, 2020
概括
研究人员开发了一种多功能基工具包,用于精确地选择化的交叉合. 这种方法克服了对复杂分子的反应控制的挑战,使高度替代的合成成为可能.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 控制化学反应中的位置选择性对于合成复杂分子至关重要.
- 非共价相互作用为指导反应提供了一个有希望的策略,但它们在密切间隔的位置上的静电相互作用的有效性仍在争论中.
- 多重化的选择性交叉合通常会导致常规方法的复杂混合物.
研究的目的:
- 通过静电相互作用,研究实现对选择性交叉合反应的精细控制的可行性.
- 开发一套实用的工具来控制木-米亚乌拉和布赫瓦尔德-哈特维格多重化的位置选择性.
- 通过选择性交叉合来证明复杂,高度替代的的合成.
主要方法:
- 应用一个由两种硫化联体和五种不同尺寸的基组成的10件工具包.
- 系统选基/基组合的苏苏基-米亚乌拉和布克瓦尔德-哈特维格合反应.
- 在一系列异构二化和三化基板上测试方法.
主要成果:
- 在交叉合反应中,基组合有效控制了位点选择性.
- 在具有挑战性的同位素化上取得了成功的苏苏基-米亚乌拉和布赫瓦尔德-哈特维格合.
- 开发的方法避免了通常在标准配体中观察到的难以处理的混合物.
结论:
- 通过精心挑选的连接物/基组的微调静电相互作用,可以精确控制位置选择性.
- 该工具包提供了选择性交叉合的实用解决方案,促进复杂的多替代基团的合成.
- 这种方法扩大了交叉合反应的合成实用性,用于构建复杂的芳香结构.
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