Conformational Dependence of the Disulfide Stretching Frequency in Cyclic Model Compounds

Article abstract of DOI:10.1021/ja00266a023

Disulfide stretching frequencies and framework torsion angles are reported for 12-S-S bonds that occur in 7 crystalline, cyclic molecules, 2 of which are CH2, CD2 isotopomers.The S-S streching frequency increases with increasing CCSS torsion angle above about 100 deg. but is intensive to this angle over the range 37-100 deg.Normal coordinate calculations using an optimized Urey-Bradely force field confirm that the behavior has a conformational origin.Collectively, the results support and somewhat extend the Sugeta, Go, and Miyazawa picture of the conformational dependence of the disulfide streching frequency.