A Predictive Model Towards Site-Selective Metalations of Functionalized Heterocycles, Arenes, Olefins, and Alkanes using TMPZnCl·LiCl was written by Balkenhohl, Moritz;Jangra, Harish;Makarov, Ilya S.;Yang, Shu-Mei;Zipse, Hendrik;Knochel, Paul. And the article was included in Angewandte Chemie, International Edition in 2020.SDS of cas: 322-46-3 This article mentions the following:
The development of a predictive model towards site-selective deprotometalation reactions using TMPZnCl·LiCl is reported (TMP = 2,2,6,6-tetramethylpiperidinyl). The pKa values of functionalized N-, S-, and O-heterocycles, arenes, alkenes, or alkanes were calculated and compared to the exptl. deprotonation sites. Large overlap (>80%) between the calculated and empirical deprotonation sites was observed, showing that thermodn. factors strongly govern the metalation regioselectivity. In the case of olefins, calculated frozen state energies of the deprotonated substrates allowed a more accurate prediction. Addnl., various new N-heterocycles were analyzed and the metalation regioselectivities rationalized using the predictive model. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3SDS of cas: 322-46-3).
Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.SDS of cas: 322-46-3