Novel η3-Allylpalladium-Pyridinylpyrazole Complex: Synthesis, Reactivity, and Catalytic Activity for Cyclopropanation of Ketene Silyl Acetal with Allylic Acetates was written by Satake, Akiharu;Nakata, Tadashi. And the article was included in Journal of the American Chemical Society in 1998.Application of 19959-77-4 This article mentions the following:
Novel cationic η3-allylpalladium-pyridinylpyrazole complexes I (R = Me, But) were synthesized from 3-alkyl-5-(2-pyridinyl)pyrazole and η3-allylpalladium chloride dimer in the presence of AgBF4. Cationic complexes I were converted into neutral complexes II under basic conditions. These complexes were characterized by 1H, 13C, and 15N NMR studies. Neutral complexes II have high catalytic activity for cyclopropanation of ketene silyl acetals with allylic acetates. Comparison of the cationic and neutral complexes and the reaction mechanism of cyclopropanation were discussed. In the experiment, the researchers used many compounds, for example, 2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4Application of 19959-77-4).
2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4) belongs to pyrazole derivatives. Pyrazole has two ring nitrogen atoms in which N1 is pyrrolic and N2 is pyridine-like. The N1 nitrogen is not reactive but is deprotonated in the presence of a base-forming anion. The pyrazole ring is resistant to oxidation and reduction but the groups, such as alkyl and formyl attached to the ring, are oxidized to respective acids. Only electrolytic oxidation, ozonolysis, and a strong base cause ring opening.Application of 19959-77-4
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics