In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Syntheses of sterically hindered zwitterionic pyridinium phenolates as model compounds in nonlinear optics. Part 2., published in 2008-04-30, which mentions a compound: 14248-66-9, mainly applied to zwitterionic pyridinium phenolates preparation model compound nonlinear optic, Quality Control of 3,5-Dimethyl-4-nitropyridine 1-oxide.
Pyridinium phenolates possess a dissym. delocalized π-electron system providing a huge quadratic nonlinearity. They are a promising class of mols. for applications in photoelectronics and photonics. Semiempirical calculations indicate that the interplanar angle between the two aromatic rings leads to enhancement in the NLO properties of these compounds The confirmation of this feature may be provided by the study of a new series of sterically hindered pyridinium phenolates bearing two tert-Bu substituents at the ortho position(s) of the phenolate functionality. Such bulky groups would enhance the solubility of zwitterions in organic solvents and would limit the formation of aggregates. Their efficient preparations by using Suzuki cross-coupling reactions involving 3,5-dialkylated 4-bromopyridine N-oxides are described.
After consulting a lot of data, we found that this compound(14248-66-9)Quality Control of 3,5-Dimethyl-4-nitropyridine 1-oxide can be used in many types of reactions. And in most cases, this compound has more advantages.
Reference:
Isoxazole – Wikipedia,
Isoxazole | C3H3NO – PubChem