The synthesis and stereochemical assignment of crypto-optically active ²H₃-tri-phenyl methane

According to the Cahn-Ingold-Prelog rules of defining enantiomers as either “S” or “R”, the absolute configuration of enantiomers determines the direction in which each enantiomer rotates the plane of polarized light. However, sometimes due to the electronic properties of a chiral molecule, the optical rotation can’t be measured. Therefore, the determination of the absolute configuration of such compounds remains extremely challenging.

In this work, we report the synthesis and spectroscopic investigation of unprecedented crypto-optically active ²H_3­­-tri-phenylmethane. The chirality in this molecule comes exclusively due asymmetric positional distribution of the three deuterium atoms (ortho, meta and para), and this slight change of the nuclei at the aryl group presents formidable challenges towards the determination of its absolute configuration.

The presented synthesis and the determination of absolute configuration made using VCD will be presented for the first time. We believe that our hypothesis will open new horizons in the development of innovative materials, and will help in understanding the secrets of the mysterious hidden chirality substance.

References:

Angew. Chem. Int. Ed. 2015, 54,13106–13109