Cyclic and linear dimers as well as the solvate H-bonded complexes of the Z and E isomers of 2-pyrrolyl-7-hydroxy-2-methylidene-2,3-dihydro-1H-inden-1-one 1 were investigated by theoretical calculations, and their formation was proved by FT-IR and UV spectroscopy. In dimers, both strengthening and weakening of the intramolecular component of the bifurcated hydrogen bond are observed depending on the type of the formed intermolecular hydrogen bond. The effect of proton donors MeOH, HCN, and proton acceptor DMSO on the intramolecular components in solvent H-bonded complexes is discussed. A larger energy gap in the 1-E than in 1-Z isomer allows to predict photoinduced isomeric transition 1-Е → 1-Z in nonpolar aprotic solvents.
- hydrogen bonds
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry