Stereoselective self-sorting on surfaces: transcription of chiral information

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.