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The novel bench-stableN-quaternized keteneN,O-acetal, C16H19N2O+·CF3O3S−, was synthesized and its structure determined. The title compound is a rare example of a pyridinium ketene hemiaminal for which a crystal structure has been determined, joining the 2-chloro-1-(1-ethyoxyethenyl)pyridin-1-ium trifluoromethanesulfonate salt from which it was synthesized. The cationic species of the title compound can be defined by three individually planar fragments assembling into a non-coplanar cation. The phenyl substituent extending from the amino nitrogen atom and the ethyoxyvinyl substituent extending from the pyridine N atom are oriented on the same side of the molecule and maintain the closest coplanar relationship of the three fragments. Supramolecular interactions are dominated by C—H...O interactions from the cation to the SO3side of the trifluoromethanesulfonate anion, forming a two-dimensional substructure.
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Influence of Aryl Substituents on the Alignment of Ligands in the Dirhodium Tetrakis(1,2,2‐Triarylcyclopropane‐ carboxylate) Catalysts
Abstract Computational studies revealed that dirhodium tetrakis(1,2,2‐triarylcyclopropanecarboxylate) (Rh2(TPCP)4) catalysts adopt distinctive high symmetry orientations, which are dependent on the nature of the aryl substitution pattern. The parent catalyst, Rh2(TPCP)4, and those with ap‐substituent at the C1 aryl, such as Rh2(p‐BrTPCP)4and Rh2(p‐PhTPCP)4, adopt aC2‐symmetric structure. Rh2(3,5‐di(p‐tBuC6H4)TPCP)4, 3,5‐disubstituted at the C1 aryl, adopts aD2‐symmetric structure, whereas catalysts with ano‐substituent at the C1 aryl, such as Rh2(o‐Cl‐5‐BrTPCP)4,adopt aC4‐symmetric structure.
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- Award ID(s):
- 1700982
- PAR ID:
- 10192954
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 1867-3880
- Format(s):
- Medium: X Size: p. 174-179
- Size(s):
- p. 174-179
- Sponsoring Org:
- National Science Foundation
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