The Chirality Chain in Valine: How the Configuration at the C(α) Position through the O(cis)C′C(α)N Torsional System Leads to Distortion of the Planar Group C(α)C′(O(cis))O(trans) to a Flat Tetrahedron

Solid‐state structures, based on a Cambridge Structural Database (CSD) search, show that there is a C(α)N/C′O(cis) attraction in the torsional system O(cis)C′C(α)N of valine, causing a chirality chain. The C(α) configuration controls the chirality of the rotation around the C′−C(α) bond, which in turn induces a distortion of the planar unit C(α)C′(O)O to a flat asymmetric tetrahedron. Conformational “reactions” take place in an energy profile with respect to clockwise and counterclockwise rotation around the C′−C(α) bond as well as stretching and flattening of the tetrahedron. The molecular property C(α)N/C′O(cis) attraction of valine is maintained in its di‐ and tripeptides.