Three cyclopentadienylmolybdenum(II) propionyl complexes featuring triarylphosphine ligands with different para substituents, namely, dicarbonyl(η 5 -cyclopentadienyl)propionyl(triphenylphosphane-κ P )molybdenum(II), [Mo(C 5 H 5 )(C 3 H 5 O)(C 18 H 15 P)(CO) 2 ], ( 1 ), dicarbonyl(η 5 -cyclopentadienyl)propionyl[tris(4-fluorophenyl)phosphane-κ P ]molybdenum(II), [Mo(C 5 H 5 )(C 3 H 5 O)(C 18 H 12 F 3 P)(CO) 2 ], ( 2 ), and dicarbonyl(η 5 -cyclopentadienyl)propionyl[tris(4-methoxyphenyl)phosphane-κ P ]molybdenum(II) dichloromethane solvate, [Mo(C 5 H 5 )(C 3 H 5 O)(C 21 H 21 O 3 P)(CO) 2 ]·CH 2 Cl 2 , ( 3 ), have been prepared from the corresponding ethyl complexes via phosphine-induced migratory insertion. These complexes exhibit four-legged piano-stool geometries with molecular structures quite similar to each other and to related acetyl complexes. The extended structures of the three complexes differ somewhat, with the para substituent of the triarylphosphine of ( 2 ) (fluoro) or ( 3 ) (methoxy) engaging in non-classical C—H...F or C—H...O hydrogen-bonding interactions. The structure of ( 3 ) exhibits modest disorder in the position of one Cl atom of the dichloromethane solvent, which was modeled with two sites showing approximately equivalent occupancies [0.532 (15) and 0.478 (15)].
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Crystal structure of the [(THF)Cs(μ-η 5 :η 5 -Cp′) 3 Yb] n oligomer
The green compound poly[(tetrahydrofuran)tris[μ-η 5 :η 5 -1-(trimethylsilyl)cyclopentadienyl]caesium(I)ytterbium(II)], [CsYb(C 8 H 13 Si) 3 (C 4 H 8 O)] n or [(THF)Cs(μ-η 5 :η 5 -Cp′) 3 Yb II ] n was synthesized by reduction of a red THF solution of (C 5 H 4 SiMe 3 ) 3 Yb III with excess Cs metal and identified by X-ray diffraction. The compound crystallizes as a two-dimensional array of hexagons with alternating Cs I and Yb II ions at the vertices and cyclopentadienyl groups bridging each edge. This, based off the six-electron cyclopentadienyl rings occupying three coordination positions, gives a formally nine-coordinate tris(cyclopentadienyl) coordination environment to Yb and the Cs is ten-coordinate due to the three cyclopentadienyl rings and a coordinated molecule of THF. The complex comprises layers of Cs 3 Yb 3 hexagons with THF ligands and Me 3 Si groups in between the layers. The Yb—C metrical parameters are consistent with a 4 f 14 Yb II electron configuration.
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- Award ID(s):
- 1855328
- NSF-PAR ID:
- 10232081
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 76
- Issue:
- 7
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 1131 to 1135
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1107/S2056989020008051
