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Origins of halogen effects in bioorthogonal sydnone cycloadditions.

ABSTRACT: Halogen substituents increase sydnone cycloaddition reactivities substantially. Fluoro-sydnones are superior to bromo- and chloro-sydnones, and can achieve extremely high second-order rate constants with strained alkynes. Computational studies have revealed the fluorine substituent increases the reactivity of sydnone mainly by lowering its distortion energy.

SUBMITTER: Tao H

PROVIDER: S-EPMC5953849 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Origins of halogen effects in bioorthogonal sydnone cycloadditions.

Tao Huimin H Liu Fang F Zeng Ruxin R Shao Zhuzhou Z Zou Lufeng L Cao Yang Y Murphy Jennifer M JM Houk K N KN Liang Yong Y

Chemical communications (Cambridge, England) 20180501 40

Halogen substituents increase sydnone cycloaddition reactivities substantially. Fluoro-sydnones are superior to bromo- and chloro-sydnones, and can achieve extremely high second-order rate constants with strained alkynes. Computational studies have revealed the fluorine substituent increases the reactivity of sydnone mainly by lowering its distortion energy. ...[more]

PMID: 29707720

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