Base hydrolysis of bis(ethylenediamine)cobalt(III) complexes containing chelated thioether and selenoether ligands. Observation of dramatic medium effects

Roecker, Lee; Deutsch, Edward

doi:10.1021/ic00195a006

Cited by 9 publications

(7 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[9] In addition, the coordination chemistry of urea, [10][11][12] thiourea, [13] and substituted urea ligands [14][15][16] has been of general interest over many years. Continuing our interest in the coordination of sulfur-containing ligands to Co III [17][18][19] we examined the coordination of the N,N 0 -substituted thiourea ligands shown in Fig. 1 to the robust [(en) 2 Co] 3þ fragment.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterisation of [(en)2Co]3+ Complexes Coordinated by Substituted Thiourea Ligands

et al. 2013

Self Cite

View full text Add to dashboard Cite

Substituted thiourea ligands bind in a bidentate manner forming a four-membered ring through the sulfur atom and a deprotonated thiourea nitrogen atom when reacted with [(en)2Co(OSO2CF3)2]+ in tetramethylene sulfone. Reaction of unsymmetrical ligands results in the formation of coordination isomers, some of which can be separated by column chromatography using Sephadex SPC-25. Coordination isomers are easily distinguishable based on visible and 1H NMR spectroscopy . Twelve para-substituted and one meta-substituted ligands were studied: N,N′-dibenzylthiourea (1a); N-(R)phenyl-N′-benzylthiourea {R = H (2a), NO2 (2b), CH3 (2c)}; N-(R)phenyl-N′-(R′)phenylthiourea {R, R′: H, H (3a), H, CH3 (3b), OCH3, NO2 (3c), CH3, NO2 (3d)}; N-methyl-N′-(R)phenylthiourea {R = H (4a), CH3 (4b), OCH3 (4c), NO2 (4d), 3-CH3 (4e)}. The solid state structure (X-ray) of one isomer of Co-4a as its perchlorate salt confirms the coordination mode suggested by 1H NMR spectroscopy and shows that the Co–N bond trans to the coordinated thiourea sulfur induces a structural trans effect of 0.019 Å.

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterisation of [(en)2Co]3+ Complexes Coordinated by Substituted Thiourea Ligands

et al. 2013

Self Cite

View full text Add to dashboard Cite

show abstract

“…The same accuracy was obtained over a range of 5 to 200 points using the first 2 half-lives of data. This method was also tested by evaluating the reaction of [(en) 2 Co(SCH 2 CH 2 NH 2 )] 2ϩ in 1.0 M acrylamide (1.0 M HCl, 25.0°C) [12,13]. During this reaction the coordinated thiolate reacts with the olefin to yield a coordinated thioether ligand and the solution changes color from brown to orange.…”

Section: (6)mentioning

confidence: 99%

Analysis of first-order kinetic data by a differential technique

Roecker

Lee

Liu

et al. 1997

Int. J. Chem. Kinet.

Self Cite

View full text Add to dashboard Cite

A differential method for analyzing first-order kinetic data is presented. While the essence of this approach has been known for almost a century, the use of computers to collect, store, and manipulate data has reenergized this innovative idea. Based on the equation ln dA t /dt ϭ ln k(A o Ϫ A ϱ ) Ϫ kt, plots of ln dA t /dt vs. t were found to be linear for both simulated kinetic data and data collected for the reaction of [(en) 2 Co(SCH 2 CH 2 NH 2 )] 2ϩ with acrylamide. The rate constants for the reaction obtained by this method are identical to those obtained by the infinite-time method of analysis, but do not require infinite-time measurements in their evaluation.

show abstract

“…Base hydrolysis of cobalt(III) compounds with 2-aminoethyl sulphide ligands (en = 1,2-ethanediamine) …”

Section: Introductionmentioning

confidence: 98%

“…Coordination compounds with 2-aminoethyl sulfides, H 2 NCH 2 CH 2 −S−R, reacts similarly when R is a simple alkyl group. In this case, however, the ligand is retained singly coordinated at the cobalt(III) by the amino group (Figure ). , …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Making a Robust Carbon−Cobalt(III) Bond

Larsen

Madsen

Kofod³

et al. 2009

Inorg. Chem.

View full text Add to dashboard Cite

The coordination ion with a well-characterized carbon-cobalt(III) bond, the (1,4,7-triazacyclononane)(1,6-diamino-3-thia-4-hexanido)cobalt(III) dication, [Co(tacn)(C-aeaps)](2+) (aeaps, for aminoethylaminopropylsulfide), has been reacted with iodomethane, and the S-methyl thionium derivative has been isolated. The crystal structure of the resulting [Co(tacn)(C-aeaps-SCH(3))]Br(3) x 3 H(2)O at 122 K has been determined by X-ray diffraction techniques to verify the structure. The crystal structure determination shows that the carbon-cobalt bond length is even shorter (2.001(4) A) than in [Co(aeaps)(C-aeaps)](2+) (2.026(3) A), while its trans elongating effect is less pronounced. The (1,4,7-triazacyclononane)(1,6-diamino-3-thia-4-hexanido)cobalt(III) dication [Co(tacn)(C-aeaps)](2+) (aeaps, for aminoethylaminopropylsulfide) reacts relatively fast with acid, for example, with NH(4)(+) to form a sulfur-bound aeaps ligand. The [Co(tacn)(C-aeaps-SCH(3))](3+) ion is remarkably robust in strongly acidic aqueous solution in spite of the supposed high basicity of the carbon anion. However, with a large excess of iodide, the methyl group can be removed as iodomethane. The experimentally obtained distances around cobalt(III) for the three involved coordination ions are compared to those computed from DFT with different standard choices for functionals and basis sets. The agreements range from poor to modest depending of the choice of functionals. It is noteworthy, however, that a sulfur 3p orbital in [Co(tacn)(C-aeaps)](2+) participates in bonding to cobalt(III), having implications for the transformation between the carbon- and sulfur-bound forms of the aeaps ligand.

show abstract

Base hydrolysis of bis(ethylenediamine)cobalt(III) complexes containing chelated thioether and selenoether ligands. Observation of dramatic medium effects

Cited by 9 publications

References 9 publications

Synthesis and Characterisation of [(en)2Co]3+ Complexes Coordinated by Substituted Thiourea Ligands

Synthesis and Characterisation of [(en)2Co]3+ Complexes Coordinated by Substituted Thiourea Ligands

Analysis of first-order kinetic data by a differential technique

Making a Robust Carbon−Cobalt(III) Bond

Contact Info

Product

Resources

About