The absolute configuration of a subtly chiral molecule has been determined using Raman optical activity and quantum mechanics. Werner Hug and his colleagues at the University of Fribourg, Switzerland, obtained the configuration of (R)-[2H1, 2H2, 2H3]-neopentane a molecule in which the central carbon is surrounded by four methyl groups bearing differing numbers of hydrogen isotopes.
For those who don’t know, a molecule is chiral (or handed) by definition if the left and right hand forms cannot be superimposed on to each other (a pair of hands, or gloves, for that matter are archetypally chiral (which comes from the Greek for hand).
The left and right-handed forms, or enantiomers, of (R)-[2H1, 2H2, 2H3]-neopentane are so similar that chemists had consigned this oddity to the lab shelf having given up any hope of distinguishing between its enantiomers. But not Hug. He and his colleagues were determined to push the limits of Raman spectroscopy to take this molecule back off the shelf and provide us with new insights into the nature of chirality.
Chirality itself lies at the heart of life on earth, but understanding the origin of the homochirality seen in nature remains a serious challenge, the new insights from Hug et al provides an important clue as to how isotopes may have played a role.
Hug et al publish details of their work in Nature.