Unusual temperature-sensitive protonation behaviour of 4-(dimethylamino)pyridine was written by Genaev, Alexander M.;Salnikov, George E.;Koltunov, Konstantin Yu.. And the article was included in Organic & Biomolecular Chemistry in 2021.Recommanded Product: 700-16-3 The following contents are mentioned in the article:
Stimuli-responsive and, in particular, temperature-responsive smart materials have recently gained much attention in a variety of applications. On the other hand, 4-(dimethylamino)pyridine (DMAP) and related structures are widely used as nucleophilic catalysts and also as specific parts of rationally designed mols., where reversible reactions of the pyridinic nitrogen with electrophiles are involved. In our study, we have found an unexpectedly significant impact of temperature on the protonation degree of DMAP derivatives, especially in the case of protonation of the 4-(dimethylamino)-1-(2,3,5,6-tetrafluoropyridin-4-yl)pyridinium cation, derived from the reaction of DMAP with pentafluoropyridine. Thus, when dissolved in the TfOH-SO2ClF-CD2Cl2 acid system at 30掳C, this cation underwent a slight (<7%) protonation on the dimethylamino group, while the temperature decrease to -70掳C resulted in its complete protonation. Notably, such a scale of this phenomenon has never been observed before for other weak nucleophiles, being many times lower at the same change of temperature The mechanistic aspects of these intriguing results are discussed. This study involved multiple reactions and reactants, such as 2,3,4,5,6-Perfluoropyridine (cas: 700-16-3Recommanded Product: 700-16-3).
2,3,4,5,6-Perfluoropyridine (cas: 700-16-3) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the 蟺-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the 蟽 bonds. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Recommanded Product: 700-16-3