Bis(cyclopentadienyl) titanium dinitrogen chemistry: Synthesis and characterization of a side-on bound haptomer

Tamara E. Hanna; Wesley H. Bernskoetter; Marco W. Bouwkamp; Emil Lobkovsky; Paul J. Chirik

doi:10.1021/om0611913

Bis(cyclopentadienyl) titanium dinitrogen chemistry: Synthesis and characterization of a side-on bound haptomer

Tamara E. Hanna, Wesley H. Bernskoetter, Marco W. Bouwkamp, Emil Lobkovsky, Paul J. Chirik

Research output: Contribution to journal › Article › peer-review

59 Scopus citations

Abstract

The titanocene dinitrogen complex [(η⁵-C₅H ₂-1,2,4-Me₃)₂Ti]₂(μ₂, η²,η²-N₂) (1-N₂) has been prepared both by dihydrogen reductive elimination from the in situ generated monohydride derivative and by alkali metal reduction of the corresponding monoiodide. In the solid state, 1-N₂ contains a side-on bound N ₂ ligand with an N-N bond length of 1.216(3) Å, consistent with a significant contribution from a two-electron-reduced diazenido ([N ₂]^2-) fragment. Attempts to maintain side-on coordination of the N₂ ligand but increase the wedge dihedral by introducing isopropyl or tert-butyl substituents induced a change in hapticity to end-on and a less activated bridging dinitrogen ligand. The ansa-titanocene dinitrogen complexes rac-[Me₂Si(η⁵-C₅H ₂-2-SiMe₃-4-^tBu)₂Ti] ₂(μ₂,η¹,η¹-N ₂)(4-N₂) and [Me₂Si(η⁵-C ₅Me₄)(η⁵-C₅H₃3- ^tBu)Ti]₂(μ₂,η¹, η¹-N₂) (5-N₂) have also been prepared and crystallographically characterized and shown to have weakly activated, end-on dinitrogen ligands. The latter example coordinates two additional equivalents of N₂ upon cooling under a dinitrogen atmosphere in pentane solution.

Original language	English (US)
Pages (from-to)	2431-2438
Number of pages	8
Journal	Organometallics
Volume	26
Issue number	9
DOIs	https://doi.org/10.1021/om0611913
State	Published - Apr 23 2007
Externally published	Yes

All Science Journal Classification (ASJC) codes

Physical and Theoretical Chemistry
Organic Chemistry
Inorganic Chemistry

Access to Document

10.1021/om0611913

Cite this

@article{711d6f9cc4e04d2e8506e34bb0ca3594,

title = "Bis(cyclopentadienyl) titanium dinitrogen chemistry: Synthesis and characterization of a side-on bound haptomer",

abstract = "The titanocene dinitrogen complex [(η5-C5H 2-1,2,4-Me3)2Ti]2(μ2, η2,η2-N2) (1-N2) has been prepared both by dihydrogen reductive elimination from the in situ generated monohydride derivative and by alkali metal reduction of the corresponding monoiodide. In the solid state, 1-N2 contains a side-on bound N 2 ligand with an N-N bond length of 1.216(3) {\AA}, consistent with a significant contribution from a two-electron-reduced diazenido ([N 2]2-) fragment. Attempts to maintain side-on coordination of the N2 ligand but increase the wedge dihedral by introducing isopropyl or tert-butyl substituents induced a change in hapticity to end-on and a less activated bridging dinitrogen ligand. The ansa-titanocene dinitrogen complexes rac-[Me2Si(η5-C5H 2-2-SiMe3-4-tBu)2Ti] 2(μ2,η1,η1-N 2)(4-N2) and [Me2Si(η5-C 5Me4)(η5-C5H33- tBu)Ti]2(μ2,η1, η1-N2) (5-N2) have also been prepared and crystallographically characterized and shown to have weakly activated, end-on dinitrogen ligands. The latter example coordinates two additional equivalents of N2 upon cooling under a dinitrogen atmosphere in pentane solution.",

author = "Hanna, {Tamara E.} and Bernskoetter, {Wesley H.} and Bouwkamp, {Marco W.} and Emil Lobkovsky and Chirik, {Paul J.}",

year = "2007",

month = apr,

day = "23",

doi = "10.1021/om0611913",

language = "English (US)",

volume = "26",

pages = "2431--2438",

journal = "Organometallics",

issn = "0276-7333",

publisher = "American Chemical Society",

number = "9",

}

TY - JOUR

T1 - Bis(cyclopentadienyl) titanium dinitrogen chemistry

T2 - Synthesis and characterization of a side-on bound haptomer

AU - Hanna, Tamara E.

AU - Bernskoetter, Wesley H.

AU - Bouwkamp, Marco W.

AU - Lobkovsky, Emil

AU - Chirik, Paul J.

PY - 2007/4/23

Y1 - 2007/4/23

N2 - The titanocene dinitrogen complex [(η5-C5H 2-1,2,4-Me3)2Ti]2(μ2, η2,η2-N2) (1-N2) has been prepared both by dihydrogen reductive elimination from the in situ generated monohydride derivative and by alkali metal reduction of the corresponding monoiodide. In the solid state, 1-N2 contains a side-on bound N 2 ligand with an N-N bond length of 1.216(3) Å, consistent with a significant contribution from a two-electron-reduced diazenido ([N 2]2-) fragment. Attempts to maintain side-on coordination of the N2 ligand but increase the wedge dihedral by introducing isopropyl or tert-butyl substituents induced a change in hapticity to end-on and a less activated bridging dinitrogen ligand. The ansa-titanocene dinitrogen complexes rac-[Me2Si(η5-C5H 2-2-SiMe3-4-tBu)2Ti] 2(μ2,η1,η1-N 2)(4-N2) and [Me2Si(η5-C 5Me4)(η5-C5H33- tBu)Ti]2(μ2,η1, η1-N2) (5-N2) have also been prepared and crystallographically characterized and shown to have weakly activated, end-on dinitrogen ligands. The latter example coordinates two additional equivalents of N2 upon cooling under a dinitrogen atmosphere in pentane solution.

AB - The titanocene dinitrogen complex [(η5-C5H 2-1,2,4-Me3)2Ti]2(μ2, η2,η2-N2) (1-N2) has been prepared both by dihydrogen reductive elimination from the in situ generated monohydride derivative and by alkali metal reduction of the corresponding monoiodide. In the solid state, 1-N2 contains a side-on bound N 2 ligand with an N-N bond length of 1.216(3) Å, consistent with a significant contribution from a two-electron-reduced diazenido ([N 2]2-) fragment. Attempts to maintain side-on coordination of the N2 ligand but increase the wedge dihedral by introducing isopropyl or tert-butyl substituents induced a change in hapticity to end-on and a less activated bridging dinitrogen ligand. The ansa-titanocene dinitrogen complexes rac-[Me2Si(η5-C5H 2-2-SiMe3-4-tBu)2Ti] 2(μ2,η1,η1-N 2)(4-N2) and [Me2Si(η5-C 5Me4)(η5-C5H33- tBu)Ti]2(μ2,η1, η1-N2) (5-N2) have also been prepared and crystallographically characterized and shown to have weakly activated, end-on dinitrogen ligands. The latter example coordinates two additional equivalents of N2 upon cooling under a dinitrogen atmosphere in pentane solution.

UR - http://www.scopus.com/inward/record.url?scp=34248374238&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34248374238&partnerID=8YFLogxK

U2 - 10.1021/om0611913

DO - 10.1021/om0611913

M3 - Article

AN - SCOPUS:34248374238

SN - 0276-7333

VL - 26

SP - 2431

EP - 2438

JO - Organometallics

JF - Organometallics

IS - 9

ER -

Bis(cyclopentadienyl) titanium dinitrogen chemistry: Synthesis and characterization of a side-on bound haptomer

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this