Synthesis of 1, 3 -dimethyl-3-phenylspiro [indoline ?2,2?-(2?H-l-benzopyran)]s and an investigation of the electronic absorption spectra of their merocyanine forms

Abstract

The synthesis of photochromic indoline spiropyrans containing a phenyl substituent in position 3 has been effected. The electronic absorption spectra of the colored forms of the spiropyrans obtained reveal the properties typical for merocyanine dyes.