School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala, 695551, India.
Angew Chem Int Ed Engl. 2021 Nov 15;60(47):24875-24881. doi: 10.1002/anie.202109344. Epub 2021 Sep 17.
Topochemical reactions, high-yielding solid-state reactions arising from the proximal alignment of reacting partners in the crystal lattice, do not require solvents, catalysts, and additives, are of high demand in the context of green processes and environmental safety. However, the bottleneck is the limited number of reactions that can be done in the crystal medium. We present the topochemical ene-azide cycloaddition (TEAC) reaction, wherein alkene and azide groups undergo lattice-controlled cycloaddition reaction giving triazoline in crystals. A designed monomer that arranges in a head-to-tail manner in its crystals pre-organizing the reacting groups of adjacent molecules in proximity undergoes spontaneous cycloaddition reaction in a single-crystal-to-single-crystal fashion, yielding the triazoline-linked polymer. A unique advantage of this reaction is that the triazoline can be converted to aziridine by simple heating, which we exploited for the otherwise challenging post-synthetic backbone modification of the polymer. This reaction may revolutionize the field of polymer science.
拓扑化学反应是指在晶格中反应物的近程排列引发的高产固态反应，它不需要溶剂、催化剂和添加剂，在绿色工艺和环境安全方面具有很高的需求。然而，其瓶颈在于晶体介质中可进行的反应数量有限。我们提出了拓扑烯-叠氮环加成（TEAC）反应，其中烯烃和叠氮基团在晶格控制下发生环加成反应，在晶体中生成三唑啉。设计的单体在其晶体中以头尾相连的方式排列，预组织相邻分子的反应基团接近，以单晶到单晶的方式自发进行环加成反应，生成三唑啉键合聚合物。该反应的一个独特优势是三唑啉可以通过简单加热转化为氮丙啶，我们利用这一特性对聚合物进行了原本具有挑战性的后合成主链修饰。该反应可能会彻底改变聚合物科学领域。
