CONSECUTIVE THREE-COMPONENT SYNTHESIS OF FILM LUMINESCENT INDOLONE MEROCYANINES WITH L-AMINO ACID ESTER DONORS

Prop-2-enylidene indolones substituted with L-amino acid esters are obtained in good to excellent yields in a consecutive three-component cyclocarbopalladation, Sonogashira coupling, and Michael addition sequence. While primary L-amino acid esters furnish a mixture of E , E - and E , Z -configurated diastereomers, L-proline methyl ester selectively and exclusively furnishes the E , E -isomer. As already discovered for other 3-aminoprop-2-enylidene indolones, the dropcasted films of all representatives display pronounced aggregation-induced orange-red fluorescence with large Stokes shifts, while all chromophores are nonemissive in solution. Also published in Chemistry of Heterocyclic Compounds , 2013, 49 (6), pp 860-871 http://link.springer.com/article/10.1007/s10593-013-1320-3