A chiral rhenium complex with predicted high parity violation effects: synthesis, stereochemical characterization by VCD spectroscopy and quantum chemical calculations

November 2, 2018

Title

A chiral rhenium complex with predicted high parity violation effects: synthesis, stereochemical characterization by VCD spectroscopy and quantum chemical calculations

Author

Nidal Saleh, Samia Zrig, Thierry Roisnel, Laure Guy, Radovan Bast, Trond Saue, Benoît Darquié, Jeanne Crassous

Year

2013

Journal

Physical Chemistry Chemical Physics

Abstract

With their rich electronic, vibrational, rotational and hyperfine structure, molecular systems have the potential to play a decisive role in precision tests of fundamental physics. For example, electroweak nuclear interactions should cause small energy differences between the two enantiomers of chiral molecules, a signature of parity symmetry breaking. Enantioenriched oxorhenium(VII) complexes S-(−)- and R-(+)-3 bearing a chiral 2-methyl-1-thio-propanol ligand have been prepared as potential candidates for probing molecular parity violation effects via high resolution laser spectroscopy of the Re[double bond, length as m-dash]O stretching. Although the rhenium atom is not a stereogenic centre in itself, experimental vibrational circular dichroism(VCD) spectra revealed a surrounding chiral environment, evidenced by the Re[double bond, length as m-dash]O bond stretching mode signal. The calculated VCD spectrum of the Renantiomer confirmed the position of the sulfur atom cis to the methyl, as observed in the solid-state X-ray crystallographic structure, and showed the presence of two conformers of comparable stability. Relativistic quantum chemistry calculations indicate that the vibrational shift between enantiomers due to parity violation is above the target sensitivity of an ultra-high resolution infrared spectroscopy experiment under active preparation.

Instrument

FVS-6000

Keywords

Vibrational circular dichroism, rhenium complex, parity violation