A QSPR-approach to the estimation of the pKHB of six-membered nitrogen-heterocycles using quantum mechanically derived descriptors was written by Hennemann, Matthias;Clark, Timothy. And the article was included in Journal of Molecular Modeling [online computer file] in 2002.Safety of 2-Isopropylpyridine This article mentions the following:
Descriptors derived from semiempirical (AM1) MO calculations have been used to construct a quant. structure-property relationship (QSPR) for the thermodn. hydrogen-bond basicity, pKHB, of a series of six-membered aromatic nitrogen-heterocycles. The resulting model uses four-descriptors (the Coulson charge on the nitrogen atom, the energy of the localized nitrogen lone-pair orbital, the p-orbital contribution to this MO and an accessibility angle). The model gives r2ev=0.95 for 51 compounds with a standard deviation between calculation and experiment of 0.13 log units. In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Safety of 2-Isopropylpyridine).
2-Isopropylpyridine (cas: 644-98-4) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-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 σ bonds. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Safety of 2-Isopropylpyridine