Ab initio calculation of optical rotation in (P)-(+)-[4]triangulane.
Optical rotation, the angle through which plane-polarized light rotates when passed through an enantiomerically pure medium, plays a vital role in the determination of the absolute configurations of chiral molecules such as natural products. We describe new quantum mechanical methodology designed to assist in this endeavor by providing high-accuracy computational optical rotatory dispersion data for matching to experimental results. Comparison between theory and experiment for the rigid, helical molecule trispiro[2.0.0.2.1.1]nonane [also known as (P)-(+)-[4]triangulane], recently synthesized with enantiomeric purity, shows that the coupled cluster quantum chemical model provides superb agreement for optical rotation across a wide range of wavelengths (589-365 nm), with errors averaging only 1%.
Crawford
T Daniel
TD
Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA. crawdad@vt.edu
Owens
Lesley S
LS
Tam
Mary C
MC
Schreiner
Peter R
PR
Koch
Henrik
H