X-ray structures and photophysical properties of Tris(1-naphthyl)silicon(IV) derivatives

Abstract

Silyl-substituted naphthalene derivatives, tris(1-napthyl)silicon (IV) chloride (1), tris(1-napthyl)silicon (IV) hydroxide (2) and tris(1-napthyl)silicon (IV)-n-butoxide (3) have been structurally characterized by single-crystal X-ray diffraction. The close intermolecular proximity of the naphthyl substituents groups in 1–3 results in a variety of C–H---π intermolecular interactions to form 2D assemblies. The UV–vis spectra of 1–3 display bathochromic (red)-shifts and the extinction coefficients increase with respect to unsubstituted naphthalene. Quantum yield calculations indicate that the fluorescence emission efficiency of 1–3 is significantly decreased with reference to 1-trimethylsilylnaphthalene. The absorptions in the solid-state spectra are broadened and approximately 45 nm red-shifted in comparison with the spectra of 1–3 in solution.