Advanced

Coordination Complexes of Molybdenum with 3,6-Di-tert-butylcatechol. Addition Products of DMSO, Pyridine N-oxide, and Triphenylarsine Oxide to the Putative [MoVIO(3,6-DBCat)2] Monomer and Self-Assembly of the Chiral [{MoVIO(3,6-DBCat)2}4] Square

Liu, Cai-Ming; Nordlander, Ebbe LU ; Schmeh, Derek; Shoemaker, Richard and Pierpont, Cortlandt G (2004) In Inorganic Chemistry 43(6). p.2114-2124
Abstract
Molybdenum complexes of 3,6-di-tert-butylcatechol have been prepared from the reaction between [Mo(CO)6] and 3,6-di-tert-butyl-1,2-benzoquinone. A putative "[MoO(3,6-DBCat)2]" monomer is assumed to form initially by reaction with trace quantities of oxygen. Condensation of the reaction mixture leads to the formation of oligomeric products, including the [{MoO(3,6-DBCat)2}4] chiral square isolated by chromatographic separation. Molybdenum centers at the corner of the square are bridged by oxo ligands centered along edges. Four-fold and inversion crystallographic symmetry gives tetramers as either or isomers, and the crystal structure consists of parallel columns of squares with the same chirality. Addition of O-Subst (O-Subst = dmso,... (More)
Molybdenum complexes of 3,6-di-tert-butylcatechol have been prepared from the reaction between [Mo(CO)6] and 3,6-di-tert-butyl-1,2-benzoquinone. A putative "[MoO(3,6-DBCat)2]" monomer is assumed to form initially by reaction with trace quantities of oxygen. Condensation of the reaction mixture leads to the formation of oligomeric products, including the [{MoO(3,6-DBCat)2}4] chiral square isolated by chromatographic separation. Molybdenum centers at the corner of the square are bridged by oxo ligands centered along edges. Four-fold and inversion crystallographic symmetry gives tetramers as either or isomers, and the crystal structure consists of parallel columns of squares with the same chirality. Addition of O-Subst (O-Subst = dmso, pyridine N-oxide, triphenylarsine oxide) ligands to [MoO(3,6-DBCat)2] occurs selectively to give cis-[MoO(O-Subst)(3,6-DBCat)2] products. All three addition complexes are fluxional in solution. The temperature-dependent stereodymanic behavior of [MoO(dmso)(3,6-DBCat)2] has been shown to occur via a trigonal prismatic intermediate (Bailar twist) that conserves the cis disposition of oxo and dmso ligands. Electrochemical and chemical reduction reactions have been investigated for [MoO(dmso)(3,6-DBCat)2] with interest in displacement of SMe2 with formation of cis-[MoO2(3,6-DBCat)2]2-. Cyclic voltammetry shows an irreversible two-electron reduction for the complex at -0.852 V (vs Fc/Fc+). Chemical reduction using CoCp2 was observed to give a product with an electronic spectrum that is generally associated with cis-[MoO2(Cat)2]2- complexes. Structural characterization revealed that the product was [CoCp2][MoO(3,6-DBCat)2], possibly formed as the product of dmso displacement upon one-electron reduction of [MoO(dmso)(3,6-DBCat)2]. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Inorganic Chemistry
volume
43
issue
6
pages
2114 - 2124
publisher
The American Chemical Society
external identifiers
  • wos:000220295200045
  • pmid:15018535
  • scopus:1642401336
ISSN
1520-510X
DOI
10.1021/ic0354264
language
English
LU publication?
yes
id
5af4ecf1-f829-4d17-b20f-f03906908ce7 (old id 141562)
date added to LUP
2007-07-09 14:02:11
date last changed
2017-07-23 03:34:37
@article{5af4ecf1-f829-4d17-b20f-f03906908ce7,
  abstract     = {Molybdenum complexes of 3,6-di-tert-butylcatechol have been prepared from the reaction between [Mo(CO)6] and 3,6-di-tert-butyl-1,2-benzoquinone. A putative "[MoO(3,6-DBCat)2]" monomer is assumed to form initially by reaction with trace quantities of oxygen. Condensation of the reaction mixture leads to the formation of oligomeric products, including the [{MoO(3,6-DBCat)2}4] chiral square isolated by chromatographic separation. Molybdenum centers at the corner of the square are bridged by oxo ligands centered along edges. Four-fold and inversion crystallographic symmetry gives tetramers as either or isomers, and the crystal structure consists of parallel columns of squares with the same chirality. Addition of O-Subst (O-Subst = dmso, pyridine N-oxide, triphenylarsine oxide) ligands to [MoO(3,6-DBCat)2] occurs selectively to give cis-[MoO(O-Subst)(3,6-DBCat)2] products. All three addition complexes are fluxional in solution. The temperature-dependent stereodymanic behavior of [MoO(dmso)(3,6-DBCat)2] has been shown to occur via a trigonal prismatic intermediate (Bailar twist) that conserves the cis disposition of oxo and dmso ligands. Electrochemical and chemical reduction reactions have been investigated for [MoO(dmso)(3,6-DBCat)2] with interest in displacement of SMe2 with formation of cis-[MoO2(3,6-DBCat)2]2-. Cyclic voltammetry shows an irreversible two-electron reduction for the complex at -0.852 V (vs Fc/Fc+). Chemical reduction using CoCp2 was observed to give a product with an electronic spectrum that is generally associated with cis-[MoO2(Cat)2]2- complexes. Structural characterization revealed that the product was [CoCp2][MoO(3,6-DBCat)2], possibly formed as the product of dmso displacement upon one-electron reduction of [MoO(dmso)(3,6-DBCat)2].},
  author       = {Liu, Cai-Ming and Nordlander, Ebbe and Schmeh, Derek and Shoemaker, Richard and Pierpont, Cortlandt G},
  issn         = {1520-510X},
  language     = {eng},
  number       = {6},
  pages        = {2114--2124},
  publisher    = {The American Chemical Society},
  series       = {Inorganic Chemistry},
  title        = {Coordination Complexes of Molybdenum with 3,6-Di-tert-butylcatechol. Addition Products of DMSO, Pyridine N-oxide, and Triphenylarsine Oxide to the Putative [MoVIO(3,6-DBCat)2] Monomer and Self-Assembly of the Chiral [{MoVIO(3,6-DBCat)2}4] Square},
  url          = {http://dx.doi.org/10.1021/ic0354264},
  volume       = {43},
  year         = {2004},
}