Influence of an electron-acceptor substituent type on the photophysical properties of unsymmetrically substituted diphenylacetylene

•New derivatives of diphenylacetylene have been synthetized as a pull-push fluorophores.•Influence of electron-donor-acceptor substituents and solvents on photophysics of studied compounds has been studied.•Excited state dipole moment based on solvatochromic methods has been determined.

Unsymmetrically substituted diphenylacetylene derivatives containing a different type of an electron-acceptor substituent were synthetized and studied using spectroscopic methods in order to establish the influence of electron affinity of substituent on the photo physics of donor-acceptor pairs. Spectral and photophysical properties were studied in 14 solvents (non-polar, polar aprotic and protic). Influence of solvent properties on spectral and photophysical properties of studied compounds was analyzed using Catalan multi-parameter solvent scale. The change of the excited state dipole moment was estimated based on Bilot-Kawski theory.