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A Predictive Model Towards Site-Selective Metalations of Functionalized Heterocycles, Arenes, Olefins, and Alkanes using TMPZnCl?LiCl.

ABSTRACT: 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 experimental deprotonation sites. Large overlap (>80?%) between the calculated and empirical deprotonation sites was observed, showing that thermodynamic factors strongly govern the metalation regioselectivity. In the case of olefins, calculated frozen state energies of the deprotonated substrates allowed a more accurate prediction. Additionally, various new N-heterocycles were analyzed and the metalation regioselectivities rationalized using the predictive model.

SUBMITTER: Balkenhohl M

PROVIDER: S-EPMC7497272 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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A Predictive Model Towards Site-Selective Metalations of Functionalized Heterocycles, Arenes, Olefins, and Alkanes using TMPZnCl⋅LiCl.

Balkenhohl Moritz M Jangra Harish H Makarov Ilya S IS Yang Shu-Mei SM Zipse Hendrik H Knochel Paul P

Angewandte Chemie (International ed. in English) 20200608 35

The development of a predictive model towards site-selective deprotometalation reactions using TMPZnCl⋅LiCl is reported (TMP=2,2,6,6-tetramethylpiperidinyl). The pK<sub>a</sub> values of functionalized N-, S-, and O-heterocycles, arenes, alkenes, or alkanes were calculated and compared to the experimental deprotonation sites. Large overlap (>80 %) between the calculated and empirical deprotonation sites was observed, showing that thermodynamic factors strongly govern the metalation regioselectiv ...[more]

PMID: 32400069

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