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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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Low‐Temperature Thermal Formation of the Cyclic Methylphosphonic Acid Trimer [ c ‐(CH 3 PO 2 ) 3 ]
Abstract We report the formation of the cyclic methylphosphonic acid trimer [c‐(CH3PO2)3] through condensation reactions during thermal processing of low‐temperature methylphosphonic acid samples exploiting photoionization reflectron time‐of‐flight mass spectrometry (PI−ReTOF−MS) along with electronic structure calculations. Cyclic methylphosphonic acid trimers are formed in the solid state and detected together with its protonated species in the gas phase upon single photon ionization. Our studies provide an understanding of the preparation of phosphorus‐bearing potentially prebiotic molecules and the fundamental knowledge of low‐temperature phosphorus chemistry in extraterrestrial environments.
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- PAR ID:
- 10442828
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhysChem
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1439-4235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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