Conformational analysis using torsion angle notation : attempted prediction and interpretation of the steric course of the cleavage reaction between bicyclic aziridines and hydrogen fluoride in pyridine solution

Ionic liquids as media for nucleophilic ring opening fluorination of aziridines

“…Aziridines can be utilized as important building blocks for the synthesis of biologically active amine derivatives, such as amino acids, ß-lactam antibiotics and alkaloids, and considerable efforts have been made to open aziridine rings by nucleophlic substitution reaction [18][19][20][21][22][23]. A ring opening reaction of aziridines by fluoride anion is one of the most straightforward ways to access ß-fluoro amines [24][25][26][27][28][29][30][31][32][33]. There are many methods available for the nucleophilic ring opening fluorination of aziridines, using hydrogen fluoride, hydrogen fluoride-pyridine, and diethylaminosulfur trifluoride [24][25][26][27][28][29][30][31][32][33]; however, practical and convenient methods are quite restricted.…”

“…A ring opening reaction of aziridines by fluoride anion is one of the most straightforward ways to access ß-fluoro amines [24][25][26][27][28][29][30][31][32][33]. There are many methods available for the nucleophilic ring opening fluorination of aziridines, using hydrogen fluoride, hydrogen fluoride-pyridine, and diethylaminosulfur trifluoride [24][25][26][27][28][29][30][31][32][33]; however, practical and convenient methods are quite restricted. In 2004, Hou and co-workers reported that a potassium fluoride with tetrabutylammonium bisulfate in THF is quite an effective reagent system for conversion from aziridines to ß-fluoro amines in high yields [34].…”

Facile Preparation of β-Fluoro Amines by the Reaction of Aziridines with Potassium Fluoride Dihydrate in the Presence of Bu4NHSO4

“…Since functionalized aziridines are now easily accessible, the ring-opening reaction of them with fluoride should be the most convenient route to β -fluoro amines . Indeed, some reports appeared using hydrogen fluoride, hydrogen fluoride−pyridine (Olah's reagent), and diethylaminosulfur trifluoride (DAST) . However, all of these reagents have suffered from the fact that they are highly toxic and corrosive to glass, so some special care was needed.…”