2-[2,6-Diisopropylphenyl]-4-phenyl-5H-5,9b[1′,2′]-benzonaphtho[1,2-b]pyrrol-2-ium Tetrafluoroborate

Abstract

A novel α,β-unsaturated iminium salt (3) incorporated into a rigid dibenzobarrelene backbone was synthesized by heating N-(anthracen-9-ylmethyl)-2,6-diisopropylaniline (2) and 3-phenyl-2-propynal in THF in the presence of excess amounts of magnesium sulfate and 0.5 equivalents of an HBF4-Et2O complex. The molecular structure of 3 was characterized unambiguously by NMR spectroscopy and single-crystal X-ray diffraction (SCXRD) analyses. Compound 3 exhibits yellow luminescence in CH2Cl2 (λem = 516 nm) and in the solid state (λem = 517 nm) with relatively high to moderate quantum yields (ΦF(CH2Cl2) = 0.63; ΦF(solid) = 0.34).