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Abstract Relative to other cyclic poly‐phosphorus species (that is,cyclo‐Pn), the planarcyclo‐P4group is unique in its requirement of two additional electrons to achieve aromaticity. These electrons are supplied from one or more metal centers. However, the degree of charge transfer is dependent on the nature of the metal fragment. Unique examples of dianionic mononuclear η4‐P4complexes are presented that can be viewed as the simple coordination of the [cyclo‐P4]2−dianion to a neutral metal fragment. Treatment of the neutral, molybdenumcyclo‐P4complexes Mo(η4‐P4)I2(CO)(CNArDipp2)2and Mo(η4‐P4)(CO)2(CNArDipp2)2with KC8produces the dianionic, three‐legged piano stool complexes, [Mo(η4‐P4)(CO)(CNArDipp2)2]2−and [Mo(η4‐P4)(CO)2(CNArDipp2)]2−, respectively. Structural, spectroscopic, and computational studies reveal a similarity to the classic η6‐benzene complex (η6‐C6H6)Mo(CO)3regarding the metal‐center valence state and electronic population of the planar‐cyclic ligand π system.
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This content will become publicly available on April 15, 2026
Interactions of CO and/or H 2 O with mesoporous oxide-supported metal catalysts: the role of MSI effects
CO and/or H2O on mesoporous oxide supported metal catalysts are reviewed from our research and literature in 2020–2025, for WGS, CO oxidation, and F–T synthesis, with focuses on advanced spectroscopic techniques and metal–support interactions.
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- Award ID(s):
- 2119688
- PAR ID:
- 10627936
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 61
- Issue:
- 32
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 5917 to 5929
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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