Synthesis of 2‐(Trifluoromethyl)‐dibenzopyranones with Rhodium(III)‐catalyzed Formal anti‐Michael Addition as Key Step.

Abstract: A novel rhodium(III)‐catalyzed synthesis of 2‐(trifluoromethyl)‐dibenzopyranones from easily available 4‐(trifluoromethyl)‐<italic>p</italic>‐quinols and <italic>N</italic>‐methoxyarylamides is described. Rhodium(III)‐catalyzed formal anti‐Michael addition was proposed to be a crucial step in this [3+3] annulation with <italic>N</italic>‐methoxyarylamides as effective 1,3‐dipoles, providing a concise and efficient approach for the construction of trifluoromethyl‐containing dibenzopyranones under mild reaction conditions. [ABSTRACT FROM AUTHOR]