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Protonation of ?-Butyrolactone and ?-Butyrolactam.

ABSTRACT: ?-Butyrolactone and ?-butyrolactam were reacted in the superacidic systems XF/MF₅ (X=H, D; M=As, Sb). Salts of the monoprotonated species of ?-butyrolactone were obtained in terms of [(CH₂ )₃ OCOH]⁺ [AsF₆ ]^- , [(CH₂ )₃ OCOH]⁺ [SbF₆ ]^- and [(CH₂ )₃ OCOD]⁺ [AsF₆ ]^- and the analogous lactam salts in terms of [(CH₂ )₃ NHCOH]⁺ [AsF₆ ]^- , [(CH₂ )₃ NHCOH]⁺ [SbF₆ ]^- and [(CH₂ )₃ NDCOD]⁺ [AsF₆ ]^- . The salts were characterized by low temperature Raman and infrared spectroscopy and for both protonated hexafluoridoarsenates, [(CH₂ )₃ OCOH]⁺ [AsF₆ ]^- and [(CH₂ )₃ NHCOH]⁺ [AsF₆ ]^- , single-crystal X-ray structure analyses were conducted. In addition to the experimental results, quantum chemical calculations were performed on the B3LYP/aug-cc-pVTZ level of theory. As in both crystal structures C???F contacts were observed, the nature of these contacts is discussed with Mapped Electrostatic Potential as a rate of strength.

SUBMITTER: Beck S

PROVIDER: S-EPMC7780814 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Protonation of γ-Butyrolactone and γ-Butyrolactam.

Beck Stefanie S Feller Michael M Spies Laura L Dietrich Kai J KJ Jessen Christoph C Stierstorfer Karin K Kornath Andreas J AJ

ChemistryOpen 20201217 1

γ-Butyrolactone and γ-butyrolactam were reacted in the superacidic systems XF/MF5 (X=H, D; M=As, Sb). Salts of the monoprotonated species of γ-butyrolactone were obtained in terms of [(CH2 )3 OCOH]+ [AsF6 ]- , [(CH2 )3 OCOH]+ [SbF6 ]- and [(CH2 )3 OCOD]+ [AsF6 ]- and the analogous lactam salts in terms of [(CH2 ...[more]

PMID: 33332769

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