Study of acetylenic sulfones, sulfoxides, and sulfides by vibrational spectroscopy methods

1. In the investigated series of acetylenic sulfides, sulfoxides and sulfones the maximum indications of conjugation are manifested between the sulfide sulfur and the C≡C bond. 2. The sulfonic group practically does not enter into conjugation with the triple bond, but it does polarize it, thus increasing the acidity of the acetylenic C-H bond. 3. In its effect on the triple bond the sulfoxide group occupies an intermediate position between the S and SO2 groups.