Flow-chemistry enabled efficient synthesis of β-peptides: backbone topology vs. helix formation.

Enantiodiscriminative helix formation was observed for β-peptide H14 helices. This observation is caused by the synperiplanar orientation of H-O atoms which is more unfavorable than those for H-H interaction. The 1,2 H-O interaction leads to the destruction of the helical structure. The introduction of a double C-C bond in the backbone rules out helix formation.