Synthesis and spectral characteristics of photochromic 5′-aryl- 1′, 3′, 3′-trimethyl-6-nitro-2h-chromene-2-spiro-2′-indolines

Abstract

A number of photochromic indolinespirochromenes containing a phenyl or p-methoxyphenyl substituent in the 5′ position of the indoline portion of the molecule were synthesized. The introduction of an aryl substituent in the 5′ position gives rise to a slight bathochromic shift of the longwave absorption band of the merocyanine form of the spirochromene. © 1977 Plenum Publishing Corporation.