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"Cyclopropylidene Effect" in the 1,3-Dipolar Cycloaddition of Nitrones to Alkylidene Cyclopropanes: A Computational Rationalization.

ABSTRACT: The regioselectivity in the 1,3-dipolar cycloaddition (1,3-DC) between five-membered cyclic nitrone and methylenecyclopropane (MCP) has been studied through density functional theory (DFT) calculations. The computational study of 1,3-DC with different 1-alkyl- (or 1,1-dialkyl)-substituted alkenes and the comparison with MCP have evidenced that the electrostatic interaction has a central role in the regioselectivity of the reactions. It has been observed that the electronic effect of the substituent (donor or attractor groups) determines the polarization of the alkene double bond and the reaction mechanism, consequently determining the interaction with nitrones and favoring an orientation between this moiety and the dipolarophile.

SUBMITTER: Briccolani-Bandini L

PROVIDER: S-EPMC8279640 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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"Cyclopropylidene Effect" in the 1,3-Dipolar Cycloaddition of Nitrones to Alkylidene Cyclopropanes: A Computational Rationalization.

Briccolani-Bandini Lorenzo L Pagliai Marco M Cordero Franca M FM Brandi Alberto A Cardini Gianni G

The journal of physical chemistry. A 20210430 18

The regioselectivity in the 1,3-dipolar cycloaddition (1,3-DC) between five-membered cyclic nitrone and methylenecyclopropane (MCP) has been studied through density functional theory (DFT) calculations. The computational study of 1,3-DC with different 1-alkyl- (or 1,1-dialkyl)-substituted alkenes and the comparison with MCP have evidenced that the electrostatic interaction has a central role in the regioselectivity of the reactions. It has been observed that the electronic effect of the substitu ...[more]

PMID: 33929857

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