Soto Miguel A, Lelj Francesco, MacLachlan Mark J
Department of Chemistry , University of British Columbia , 2036 Main Mall , Vancouver , BC , V6T 1Z1 Canada . Email:
La.M.I. and LaSCAMM INSTM Sezione Basilicata , Dipartimento di Chimica , Università della Basilicata , via dell'Ateneo Lucano 10 , Potenza , 85100 Italy.
Chem Sci. 2019 Oct 4;10(44):10422-10427. doi: 10.1039/c9sc03744f. eCollection 2019 Nov 28.
Chemical protection is an essential tool in synthetic chemistry, which involves blocking reactive sites on a molecule through covalent bonds. Physical approaches, such as encapsulation and host-mediated protection, have emerged as interesting alternatives that use steric bulk to inhibit reactivity. Here, we report the protection of a redox-active viologen through its incorporation into mechanically interlocked molecules (MIMs), namely hetero[4]rotaxanes. The viologen was confined inside a host cavity and flanked by two mechanical stoppers, which allowed for permanent and transient protection. Deprotection occurred on-demand an unstoppering process, triggered by a proton transfer, polarity effect, or a thermal stimulus. We anticipate that permanent and transient mechanical stoppering could be incorporated into devices to function as molecular probes, transport/delivery systems, or stimuli-controlled degradable materials.
化学保护是合成化学中的一种重要工具，它涉及通过共价键封锁分子上的反应位点。物理方法，如封装和主体介导的保护，已成为利用空间位阻抑制反应性的有趣替代方法。在此，我们报告了通过将氧化还原活性紫精掺入机械互锁分子（MIMs），即杂[4]轮烷，对其进行保护。紫精被限制在主体腔内，并由两个机械塞子侧翼包围，这实现了永久和暂时的保护。去保护是按需发生的——这是一个由质子转移、极性效应或热刺激触发的解除封锁过程。我们预计，永久和暂时的机械封锁可纳入装置中，用作分子探针、运输/递送系统或刺激控制的可降解材料。
