A spironaphthoxazine derivative incorporating a monaza-12-crown-4 moiety at the 5'- position has been designed as a light-resistant, cation-complexable photochromic compound. Complexation of alkali metal ions by the crown moiety in the crowned spironaphthoxazine allows the spironaphthoxazine skeleton to isomerize to ita corresponding open colored form, even under dark conditions. Specifically, Li+ ...
