FT-IR and NIR spectroscopic investigation of hydrogen bonding in indole-ether systems

This paper reports FTIR and NIR spectroscopic study of hydrogen bonding between indole and different ethers in carbon tetrachloride. With increase in ether concentration increase in intensity of red-shifted band, and decrease of intensity of monomer band has been observed. The FTIR and NIR spectroscopic characteristics for N-H center dot center dot center dot O hydrogen bonded complexes and also the equilibrium constants for 1:1 complex formation are given. Influence of structural differences of ethers on hydrogen bonding was investigated using Taft equation. Good correlation has been obtained. (C) 2017 Elsevier B.V. All rights reserved.