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Reaction of bis(dicyclohexylphosphino)ethane dioxide with hydrogen peroxide leads to an extended crystalline network based on the formation of hydrogen bonds with the PO groups of the diphosphine dioxide. The structural motif of the network is characterized by X-ray diffraction. A new selective synthesis for an industrially important MEKPO (methyl ethyl ketone peroxide) dimer is described. The dimer is created by reaction of dppe dioxide (bis(diphenylphosphino)ethane dioxide) with butanone and hydrogen peroxide. This peroxide is stabilized by forming strong hydrogen bonds to the phosphine oxide groups within an extended network, which has been characterized by single crystal X-ray diffraction. Reaction of acetylacetone with hydrogen peroxide, irrespective of the presence of phosphine oxide, leads to the stereoselective formation of two dioxolanes. Both cyclic peroxides have been obtained in crystalline forms suitable for single crystal X-ray diffractions.
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Factors influencing hydrogen peroxide versus water inclusion in molecular crystals
Hydrate formation is often unavoidable during crystallization, leading to performance degradation of pharmaceuticals and energetics. In some cases, water molecules trapped within crystal lattices can be substituted for hydrogen peroxide, improving the solubility of drugs and detonation performance of explosives. The present work compares hydrates and hydrogen peroxide solvates in two ways: (1) analyzing structural motifs present in crystal structures accessed from the Cambridge Structural Database and (2) developing potential energy surfaces for water and hydrogen peroxide interacting with functional groups of interest at geometries relevant to the solid state. By elucidating fundamental differences in local interactions that can be formed with molecules of hydrogen peroxide and/or water, the analyses presented here provide a foundation for the design and selection of candidate molecules for the formation of hydrogen peroxide solvates.
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- Award ID(s):
- 1900551
- PAR ID:
- 10397922
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 24
- Issue:
- 18
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 11206 to 11212
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1cp05765k
