Ring Opening of Diketene in Superacidic Media
The reactions of diketene were investigated in the HF/MF<sub>5</sub> and DF/MF<sub>5</sub> (M = As or Sb) binary superacidic systems. Depending on the stoichiometric ratio of the Lewis acids and diketene, monoprotonated acetoacetyl fluoride and diprotonated acetoacetyl fluoride were obtained. The salts were characterized by low-temperature vibrational spectroscopy, nuclear magnetic resonance spectroscopy, and single-crystal X-ray diffraction. [CH<sub>3</sub>C(OH)CH<sub>2</sub>COF][SbF<sub>6</sub>]·HF crystallizes in monoclinic space group <i>P</i>2<sub>1</sub>/<i>n</i> with four formula units per unit cell, and [CH<sub>3</sub>C(OH)CH<sub>2</sub>C(OH)F][SbF<sub>6</sub>]<sub>2</sub>·HF in triclinic space group <i>P</i>1 with two formula units per unit cell. Ring opening is discussed together with quantum chemical p<i>K</i><sub>a</sub> calculations. Monoprotonated acetoacetyl fluoride is characterized by a six-membered ring-like structure containing an intramolecular hydrogen bond, whereas the diprotonated species constitutes a 1,3-gitonic superelectrophile.
Authors
- Alexander Nitzer (ORCID: https://orcid.org/0000-0003-4903-9603)
- Andreas Kornath (ORCID: https://orcid.org/0000-0002-7307-4516)
- Christoph Taeschler (ORCID: https://orcid.org/0000-0002-9574-754X)
- Zurwa M. Shafiq
- Sebastian Steiner (ORCID: https://orcid.org/0000-0002-5286-3567)
- U. Blumenschein
- Christoph Jessen
Institutions
- Ludwig-Maximilians-Universität München (DE)
- Lonza (Switzerland) (CH)
Publication Details
- Journal
- The Journal of Organic Chemistry
- Published
- 2024-12-16
- DOI
- https://doi.org/10.1021/acs.joc.4c02601
- Primary Topic
- Inorganic Fluorides and Related Compounds
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Deutsche Forschungsgemeinschaft
- Ludwig-Maximilians-Universität München