A new synthesis of pyridinyl trifluoromethanesulfonates via one-pot diazotization of aminopyridines in the presence of trifluoromethanesulfonic acid

One-Pot Synthesis of Chloropyridines from Aminopyridines via Diazotization

“…4-chloropyridine (2d): oil, 60%, the NMR 1 Н, 13 С data is in good agreement with [9]; m/z: 113 (M+, 100), 86 (7), 78 (60), 60 (5), 51 (23), 43 (7), 36 (5).…”

“…2,5-dichloropyridine (2c): 68%, mp 58-60°C (mp Lit.60°C [6]); m/z: 147 (M+, 100), 112 (75), 87 (10), 76 (50), 62 (15), 50 (42), 36 (5).…”

“…Recently we proposed a convenient method for the synthesis of pyridyl trifluoromethanesulfonates (pyridyl triflates) [5]. Triflate group is a good leaving group, and allows using pyridyl triflates for highly functionalized pyridines obtaining.…”

Arenediazonium salts transformations in water media: Coming round to origins

“…Synthesis of pyridyl tosylates and triflates under solvent-free conditions was described by E.A. Krasnokutskaya et al (Schemes 11 and 12) [35,36]. The authors developed a convenient procedure for diazotization of aminopyridines in water paste in presence of p-TsOH (Scheme 11) with formation of pyridyltosylates instead of diazonium salts via spontaneous diazo-group substitution.…”