Welcome to my homepage - Wolfgang Stadlbauer

120. 3-Aryl-6-methoxy-2-oxo-1,2-dihydroquinoline-4-carbonitriles As Solvent and pH Independent Green Fluorescent Dyes
Enoua G. C., Uray G., Stadlbauer W.,
in J. Heterocyclic Chem. 49 (2012) 1415–1421.

Highly fluorescent and stable 3-aryl-6-methoxy-2-oxoquinoline-4-carbonitriles 6 (lamda-exc ~408 nm and lambda-em ~510 nm) were synthesized starting from appropriate arylmalonates 2. Ring closure reaction with p-anisidine gave 4-hydroxyquinolones 3 which could be bis-chlorinated to yield quinoline 4. Regioselective hydrolysis produced reactive 4-chloroquinolones 5, which were converted to green fluorescent 4-cyano quinolones 6 using toluenesulfinates as catalysts.

Reprint as pdf-file on request

abstract scheme