One-pot syntheses of blue-luminescent 4-aryl-1-benzo[]isoindole-1,3(2)-diones by T3P activation of 3-arylpropiolic acids.

In situ activation of 3-arylpropiolic acids with T3P (-propylphosphonic acid anhydride) initiates a domino reaction furnishing 4-arylnaphtho[2,3-]furan-1,3-diones in excellent yields. Upon employing these anhydrides as reactive intermediates blue-luminescent 4-aryl-1-benzo[]isoindole-1,3(2)-diones are formed by consecutive pseudo three-component syntheses in a one-pot fashion. The Stokes shifts correlate excellently with the Hammett-Taft σ parameter indicating an extended degree of resonance stabilization in the vibrationally relaxed excited singlet state.