E-viri
Recenzirano
Odprti dostop
-
Vicini, Anna Chiara; Alozie, Diké-Michel; Courtes, Philippe; Roagna, Giulia; Aubert, Catherine; Certal, Victor; El-Ahmad, Youssef; Roy, Sébastien; Gouverneur, Véronique
Organic process research & development, 12/2021, Letnik: 25, Številka: 12Journal Article
Hydrogen bonding phase-transfer catalysis offers a convenient solution to activate safe and economical metal alkali fluorides for enantioselective nucleophilic fluorination. Herein, we demonstrate the scalability of this protocol with the fluorination of 200 g of racemic trans-N,N-dibenzyl-2-bromocyclohexan-1-amine in a mechanically stirred 1 L glass reactor using 0.5 mol % of a bis-urea organocatalyst. In these experiments, full conversions were obtained for high mixing intensities (impeller average shear rate >10 000 s–1; maximum energy dissipation per unit of mass >300 W/kg). The thermal safety of the reaction was assessed by differential scanning calorimetry and reaction calorimetry, assigning the reaction to Stoessel’s critical class 3.
