Relative to other cyclic poly‐phosphorus species (that is,
Antiaromaticity, as introduced in 1965, usually refers to monocyclic systems with 4
- NSF-PAR ID:
- 10215319
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 128
- Issue:
- 18
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 5621-5625
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract 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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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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Abstract Using molten‐salt synthetic techniques, NaNbO3(Space group
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