The coordination chemistry of (py)2BF+2 and related difluoroboron cations was written by Stephen Hartman, J.;Shoemaker, James A. W.;Janzen, Alex F.;Ragogna, Paul J.;Szerminski, W. R.. And the article was included in Journal of Fluorine Chemistry in 2003.Quality Control of 5-Methylisoxazole This article mentions the following:
The substitution and decomposition reactions of the difluorobis(pyridine)boron(III) cation, and of several substituted pyridine and other difluoroboron cations (D)2BF2+, are explored. Donor mol. displacement is greatly accelerated by the presence of electron-withdrawing meta and para pyridine substituents in (substituted pyridine)2BF2+ cations, and by electron-donating substituents on pyridine when the substituted pyridine is the attacking species. Increased steric hindrance of D in D2BF2+, and of the attacking base D’, slows or prevents displacement of D by D’. [(Py)2BF2][PF6] (py = pyridine) undergoes slow decomposition in acetone, giving initially py·BF3 and finally [py·H][BF4] as the major fluoroboron species. A 2nd decomposition pathway, giving rise to BF3OH– and several addnl. F-containing products, is favored by the presence of strong bases such as amidines and by the presence of N-H and O-H bonds. Increased susceptibility to ligand displacement facilitates the synthesis of new fluoroboron cations, but also increases the susceptibility to decomposition In the experiment, the researchers used many compounds, for example, 5-Methylisoxazole (cas: 5765-44-6Quality Control of 5-Methylisoxazole).
5-Methylisoxazole (cas: 5765-44-6) belongs to isoxazole derivatives.Synthetically, isoxazoles serve as valuable precursors for the construction of diverse molecules, including many natural products. Isoxazole can be synthesised via a variety of methods. Examples include via a 1,3-dipolar cycloaddition of nitrile oxides with alkynes.Quality Control of 5-Methylisoxazole
Referemce:
Isoxazole – Wikipedia,
Isoxazole | C3H3NO – PubChem