Breaking the Symmetry of a Meso Compound by Isotopic Substitution: Synthesis and Stereochemical Assignment of Monodeuterated cis-Perhydroazulene.

We report the synthesis and absolute configuration of monodeuterated cis-perhydroazulene (d1-1), which is a rare example of an isotopically chiral hydrocarbon whose synthesis and stereochemical analysis are known to be particularly difficult. The synthesis features nickel-boride-catalyzed deuteration that allowed formation of the diastereomerically pure cis-fused bicyclic system in d1-1. The vibrational circular dichroism results are in excellent agreement with the computed spectrum at ωB97XD/aug-cc-pVTZ, allowing unambiguous assignment of the absolute configuration of d1-1.