C–H⋯S interaction exhibits all the characteristics of conventional hydrogen bonds

Abstract

This is a tale of a pair of a hydrogen bond donor and acceptor, namely the CH donor and sulphur acceptor, neither of which is a conventional hydrogen bond participant.

C–H⋯S hydrogen bonding interactions

“…Further evidence of a HB Additional evidence for C-HÁ Á ÁS HB interactions is supported by a recent study by Wategaonkar and coworkers using both gasphase vibrational spectroscopy and DFT calculations. 36 Despite the weak nature of both the HB donor and acceptor, C-HÁ Á ÁS interactions exhibited all the characteristics of a conventional hydrogen bond, and even displayed binding strengths comparable to more traditional HB in their system. Although S is a less electronegative element than other traditional HB acceptors, S is large and polarizable, allowing it to better participate in dispersion interactions.…”

Crystal Structure of 1,1′-(1,7-Heptanediyl)bis(pyridinium) Bis(2-thioxo-1,3-dithiole-4,5-dithiolato)nickelate Double Salt

“…Recently, C-H•••S interactions have been found to stabilize crystal structures, probably by hydrogen bonding. 7,8 In this crystal, eleven types of C-H•••S interactions were observed between the cation and anion (Table 3). In other alkylene bis(pyridinium) salts (2CnPy; n = 4, 6, 8, 10, 12), only one to four types of C-H•••S interactions have been observed.…”

Novel (Phenothiazinyl)Vinyl-Pyridinium Dyes and Their Potential Applications as Cellular Staining Agents

“…The molecules in each stack are parallel to each other, but there are two values recorded for the distances between the planes passing through two adjacent molecules: one distance is 3.537 Å demonstrating π ... π interactions (C4 ... C16 and C14 ... C2) and the other distance is 3.452 Å, presenting C-H ... π interactions (C9-H8A ... C16). For the dye 3b, C-H ... S interactions were shown to behave similarly to conventional hydrogen bonds, although the sulphur is mildly electronegative compared to oxygen [12].…”