Chiral Sulfur Compounds Studied by Raman Optical Activity: tert ‐Butanesulfinamide and its Precursor tert ‐Butyl tert ‐Butanethiosulfinate

Two chiral sulfur compounds, tert ‐butyl tert ‐butanethiosulfinate ( 1 ) and tert ‐butanesulfinamide ( 2 ), with inversion of configuration, have been studied by Raman optical activity (ROA) and electronic circular dichroism combined with density functional theory calculation. With the S–S linkage in 1 , the couplings between the two tertiary carbon atoms often generate large ROA signals, whereas the tertiary carbon atom itself generally makes a large contribution to ROA signals in 2 for similar vibrational modes. The conformational dependence of ROA parameters provides probing conformation around the S–S bond from a new perspective. The simultaneous use of electronic circular dichroism and ROA is warranted to extract reliable conformational information. ROA provides a suitable candidate for the stereochemical study of chiral sulfur compounds, especially its capability of sensing the conformation around the S–S bond. Chirality 24:731–740, 2012. © 2012 Wiley Periodicals, Inc.