超分子聚合物手性的反S-型相关

Chirality of supramolecular polymers can be described by the relationship of their CD against the enantiomeric excess (ee) of the chiral building block or of the chiral template that induces the aggregation of the achiral building block. Linear or S-shaped dependence, also termed as the “majority rules effect”, has been well documented and to some extent understood, whereas the anti-S shaped dependence has yet to be explored and understood. This project aims to developing chiral supramolecular polymers that feature that unusual anti-S shaped CD-ee dependence, based on our assumption of the preferred heterochiral selectivity taking place during the supramolcular polymerization, via either self-aggregation or induced aggregation. The supramolecular polymers to be built are: (i) supramolecular polymers of achiral perylenebisimide hosts induced by chiral template guests, (ii) Ag+ coordination polymers with chiral thiol ligands, and (iii) helical aggregates of folded short-peptides bearing an N-amidothiourea motif. Meanwhile the mechanism that leads to such anti-S shaped dependence would be investigated, to in turn facilitate the designing of the chiral building block or chiral template and to develop applications, for instance, in facile and accurate determination of ee close to 100% that is highly demanded for the products in optimal asymmetric syntheses. The investigated anti-S shaped dependence in the chirality of supramolecular polymers represents a new dimension in the supramolecular chirality and shall be of significance for better understanding of the supramolecular chirality and guiding the construction of hierarchical supramolecular chiral materials.

超分子聚合物的手性常以其圆二色(CD)信号与手性因子的对映体过量值(ee)之间的关系描述。CD-ee相关呈现S-型或线型已见诸报道，但“反S-型”相关尚鲜有报道。本项目拟构建呈现“反S-型”相关的超分子聚合物体系。我们提出该类相关系因超分子诱导聚集或自聚集过程中的异手性选择性所致，据此藉由多重非共价力和双齿构筑基元，发展3类超分子聚合物体系：(i)手性客体诱导非手性苝酰亚胺主体形成的聚合物体系；(ii)半胱氨酸的硫醇配体与Ag+构筑的配位聚合物体系；(iii)基于折叠短肽的自组装体系。研究该类“反S-型”相关的形成机制，并发展其应用于接近100%之高端ee值的精确简便测定、手性放大等，推进不对称合成条件的高通量筛选和同手性起源研究。本项目将发展的“反S-型”相关是超分子手性的新特征，研究结果对于丰富、完善和全面理解超分子手性具有重要意义，更为超分子层次手性物质的精准构筑提供理论和实验基础。

传统表达超分子聚合物手性特征的CD-ee关系曲线为线型或S-型，本项目旨在构建呈反S-型CD-ee相关的超分子聚合物体系，系超分子手性研究的新发展。我们在三类聚合物体系中成功观察到反S-型手性相关，包括：(i) 引入内消旋客体物种，主导苝酰亚胺染料分子的聚集，导致反S-型手性相关，并应用于高端ee值的精确测定；(ii) 以Ag+-硫醇配位聚合物为研究平台，Ag+•••Ag+相互作用支撑的主链上悬挂的硫醇配体侧链之间亦有相互作用，据此调控硫醇配体结构，实现反S-型手性相关的构筑；(iii) 折叠短肽于水溶液中发生多级次组装，呈现反S-型手性相关，系外消旋组分优先共聚集所致。机制研究表明外消旋或内消旋聚集体的形成是导致反S-型手性相关的关键。在此基础上，系统论述了呈S-型和反S-型手性相关的超分子聚合物体系，期望通过总结发展成熟的S-型手性相关体系，推动处于初步研究阶段的反S-型手性相关体系的发展。作为拓展研究，发展了折叠短肽结构基元，用于超分子螺旋的构建，并施行分子识别和离子跨膜转运研究。研究成果不仅有助于超分子手性特征的全面理解，对非线性手性相关超分子体系的构筑有指示意义，更为超分子手性聚合物应用体系的发展提供了理论和实验基础。.在项目执行期间内，共发表学术论文17篇，其中SCI收录论文16篇，2篇论文被国际权威刊物选为封面论文。“基于动态超分子聚集体的化学传感”获教育部自然科学奖二等奖。项目负责人组织了4次国内学术会议，并5次应邀参加国际/国内学术会议。培养博士后2人，博士毕业生5人、硕士毕业生11人。本项目基本按任务书既定计划完成研究任务，并有所拓展；青年教师的整体研究水平提升明显，为学科发展注入新的动力。