SULFUR-CONTAINING CARBOXYLIC ACIDS. 5. SYNTHESIS AND STRUCTURE OF DIALKYL SULFIDES AND DIALKYL SULFOXIDES WITH VICINAL CARBOXYL OR ACYLAMINO GROUPS

Article abstract of DOI:10.1007/BF00864333

Bifunctional sulfides and sulfoxides containing carboxy, carbamoyl, or acylamino groups in the β-position are synthesized, and their IR spectra were studied.An unusual decrease in the frequencies of the carbonyl vibrations (by 20-34 cm^-1) was found for thiodipropionic acid, its amides, and bis(β-acylaminoethyl) sulfides by comparison with the corresponding sulfoxides.The low-frequency shift of the CO bond in these carbonylsulfides was not, as expected, associated with the intramolecular S...O coordination, since the x-ray structural investigation of thiodipropionic acid and bis(2-trifluoroacetylaminoethyl) sulfide did not show short intra- and intermolecular contacts involving the sulfur atom.Both structures contain intermolecular hydrogen bonds (C=O...HO or C=O...HN).Keywords: derivatives of thiodipropionic acid, 2-(acylaminoethyl) sulfides, derivatives of β,β'-sulfinyldipropionic acid, 2-(acylaminoethyl) sulfoxides, x-ray structural analysis, bis(2-trifluoroacetylaminoethyl) sulfide, molecular structure.