Mono‐O‐functionalizations of Pittsburgh Green and Their Applications

The previous synthetic strategy for the preparation of non‐fluorescent fluoresceins was mostly limited to the double addition of simple alkenes and alkynes. We report the one‐step masking of Pittsburgh Green to its mono‐alkylated or esterified compounds. Unlike previous syntheses, this strategy tolerates a broader range of functional groups as masking groups. We also demonstrate the advantage of mono‐alkylation over di‐alkylation for metal detection. The one‐step masking of Pittsburgh Green to its mono‐alkylated or esterified compounds is reported. Unlike previous syntheses, this strategy tolerates a broader range of functional groups as masking groups. The advantage of mono‐alkylation over di‐alkylation for metal detection is also demonstrated.