Unexpected one-pot method to synthesize spiro[fluorene-9,9'-xanthene] building blocks for blue-light-emitting materials.

[reaction: see text] An unexpected one-pot synthetic approach toward spiro[fluorene-9,9'-xanthene] (SFX) under excessive MeSO(3)H conditions has been developed. The key step involves a thermodynamically controlled cyclization reaction. Blue-light-emitting materials based on SFX building blocks that exhibit high thermal stability have also been synthesized.