Department of Organic Chemistry, University of Geneva, Geneva, Switzerland.
Chirality. 2013 Feb;25(2):107-13. doi: 10.1002/chir.22118. Epub 2012 Dec 10.
Templated self-sorting on surfaces has been introduced recently as a new approach to construct multicomponent architectures directly on solid oxide surfaces. In this process, two-dimensional information placed on the surface is transcribed into three-dimensional architectures with up to 97% intrinsic templation efficiency. Previously, we have shown that isosteric partners of different color do neither self-sort nor respond to templation during self-organizing surface-initiated copolymerization (co-SOSIP). To evaluate the importance of chirality in this process, co-SOSIP with mixtures of pseudo-enantiomers of isosteric partners is explored. The composition of the obtained SOSIP architectures is independent of the composition of the initiator mixtures on the surface. This absence of templation from the surface rules out the occurrence of uniform self-sorting of pseudo-enantiomeric isosters, a process similar to chiral resolution in conglomerates. Alternate self-sorting, the complementary process comparable with racemic crystallization, is indistinguishable from random mixing in structural studies. However, different photocurrent generation by pseudo-racemic compared with pseudo-homochiral photosystems support, on the functional level, that alternate self-sorting occurs with pseudo-enantiomeric partners. These results support that chirality is important for the transcription of two-dimensional information into three-dimensional architectures and suggest that alternate self-sorting dominates over uniform self-sorting as racemic crystallization dominates over chiral resolution.
最近,表面模板自组装作为一种在固体氧化物表面直接构建多组分结构的新方法被引入。在这个过程中,表面上的二维信息被转录成具有高达 97%固有模板效率的三维结构。以前,我们已经表明,在自组织表面引发共聚(co-SOSIP)过程中,不同颜色的等电子体伙伴既不自组装,也不响应模板。为了评估手性在这个过程中的重要性,探索了等电子体的假对映异构体混合物的 co-SOSIP。所得 SOSIP 结构的组成与表面上引发剂混合物的组成无关。这种来自表面的模板缺失排除了等电子体类似手性拆分的均匀自组装的发生,这是一种类似于外消旋结晶的过程。互补的交替自组装过程与外消旋结晶相似,在结构研究中无法与随机混合区分开来。然而,与假同手性光系统相比,假外消旋光系统产生不同的光电流生成,这在功能水平上支持假对映异构体伙伴发生交替自组装。这些结果表明手性对于将二维信息转录为三维结构很重要,并表明交替自组装优于均匀自组装,就像外消旋结晶优于手性拆分一样。