The first synthesis of 3‐hydroxy‐2‐(polyfluoroalkyl)chromones and their ammonium salts. 3‐hydroxychromone in the Mannich reaction

Abstract

in Wiley InterScience (www.interscience.wiley.com).3-Hydroxy-2-(polyfluoroalkyl)chromones were obtained in good yields via the nitrozation reaction of 2-(polyfluoroalkyl)chroman-4-ones with isopropyl nitrite in the presence of hydrochloric acid. Treatment of 3-acetoxy-2-(trifluoromethyl)chromone with primary amines and hydrazine gave the corresponding ammonium salts. Reaction of 3-hydroxychromone, prepared by this method, with formaldehyde and aaminoacids has been studied.

Synthesis and Transformation of Halochromones

“…Castañeda used a similar procedure under solvent-free conditions to prepare 2-trifluoromethylchromones [129]. The pioneering recent synthesis of 3-hydroxy-2-(polyfluoroalkyl)chromones involved the nitrozation of the corresponding 2-(polyfluoroalkyl)chromanones [130]. …”