School of Chemistry, the University of Edinburgh , Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom.
J Am Chem Soc. 2017 Oct 11;139(40):14232-14236. doi: 10.1021/jacs.7b07725. Epub 2017 Sep 27.
Steric bulk prevents the formation of strong bonds between Lewis acids and bases in frustrated Lewis pairs (FLPs), where latent reactivity makes these reagents transformative in small molecule activations and metal-free catalysis. However, their use as a platform for developing materials chemistry is unexplored. Here we report a fully macromolecular FLP, built from linear copolymers that containing either a sterically encumbered Lewis base or Lewis acid as a pendant functional group. The target functional copolymers were prepared by a controlled radical copolymerization of styrene with designer boron or phosphorus containing monomers. Mixtures of the B- and P-functionalized polystyrenes do not react, with the steric bulk of the functional monomers preventing the favorable Lewis acid base interaction. Addition of a small molecule (diethyl azodicarboxylate) promotes rapid network formation, cross-linking the reactive polymer chains. The resulting gel is dynamic, can self-heal, is heat responsive, and can be reshaped by postgelation processing.
空间位阻阻止了路易斯酸和路易斯碱在受阻路易斯对（FLP）之间形成强键，而在这些试剂中，潜在的反应性使得它们在小分子活化和无金属催化中具有变革性。然而，它们作为发展材料化学的平台尚未得到探索。在这里，我们报告了一个完全的高分子 FLP，由含有空间位阻路易斯碱或路易斯酸作为侧基官能团的线性共聚物构建而成。目标功能共聚物通过苯乙烯与设计的含硼或磷单体的可控自由基共聚制备。B 和 P 官能化聚苯乙烯的混合物不反应，功能单体的空间位阻阻止了有利的路易斯酸碱相互作用。添加小分子（二乙基偶氮二甲酸酯）促进快速网络形成，交联反应性聚合物链。所得凝胶是动态的，可以自修复，对热响应，并可以通过后凝胶处理进行重塑。
