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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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Identification of a prismatic P3N3 molecule formed from electron irradiated phosphine-nitrogen ices
Abstract Polyhedral nitrogen containing molecules such as prismatic P3N3- a hitherto elusive isovalent species of prismane (C6H6) - have attracted particular attention from the theoretical, physical, and synthetic chemistry communities. Here we report on the preparation of prismatic P3N3[1,2,3-triaza-4,5,6-triphosphatetracyclo[2.2.0.02,6.03,5]hexane] by exposing phosphine (PH3) and nitrogen (N2) ice mixtures to energetic electrons. Prismatic P3N3was detected in the gas phase and discriminated from its isomers utilizing isomer selective, tunable soft photoionization reflectron time-of-flight mass spectrometry during sublimation of the ices along with an isomer-selective photochemical processing converting prismatic P3N3to 1,2,4-triaza-3,5,6-triphosphabicyclo[2.2.0]hexa-2,5-diene (P3N3). In prismatic P3N3, the P–P, P–N, and N–N bonds are lengthened compared to those in, e.g., diphosphine (P2H4), di-anthracene stabilized phosphorus mononitride (PN), and hydrazine (N2H4), by typically 0.03–0.10 Å. These findings advance our fundamental understanding of the chemical bonding of poly-nitrogen and poly-phosphorus systems and reveal a versatile pathway to produce exotic, ring-strained cage molecules.
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- Award ID(s):
- 1800975
- PAR ID:
- 10305495
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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