Abstract The impact of substituents on the photochromism of some spirooxazines has been explored. A series of photochromic spiroindolino [2, 1-b][1, 4] naphthoxazine dyes was prepared with varying alkyl substitution patterns in the 3-to 6-positions of the indoline system. It was found that placing methyl functions onto the phenyl ring produced bathochromic shifts in λ max of the photomerocyanine as expected, but contrary to ...
