The Ružička large-ring synthesis or Ružička reaction or Ružička cyclization is an organic reaction in which a dicarboxylic acid is converted to a cyclic ketone via heating with a thorium oxide catalyst. The reaction is named after Lavoslav Ružička, who invented it in 1926.[1]
The reaction has been applied in the synthesis of Exaltone, a low-toxicity synthetic musk.