|
1
|
Structural Study of Model Rhodium(I) Carbonylation Catalysts Activated by Indole-2-/Indoline-2-Carboxylate Bidentate Ligands and Kinetics of Iodomethane Oxidative Addition. INORGANICS 2022. [DOI: 10.3390/inorganics10120251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The rigid-backbone bidentate ligands Indoline-2-carboxylic acid (IndoliH) and Indole-2-carboxylic acid (IndolH) were evaluated for rhodium(I). IndoliH formed [Rh(Indoli)(CO)(PPh3)] (A2), while IndolH yielded the novel dinuclear [Rh1(Indol’)(CO)(PPh3)Rh2(CO)(PPh3)2] (B2) complex (Indol’ = Indol2−), which were characterized by SCXRD. In B2, the Rh1(I) fragment [Rh1(Indol’)(CO)(PPh3)] (bidentate N,O-Indol) exhibits a square-planar geometry, while Rh2(I) shows a ‘Vaska’-type trans-[O-Rh2(PPh3)2(CO)] configuration (bridging the carboxylate ‘oxo’ O atom of Indol2−). The oxidative addition of MeI to A2 and B2 via time-resolved FT-IR, NMR, and UV/Vis analyses indicated only Rh(III)-alkyl species (A3/B3) as products (no migratory insertion). Variable temperature kinetics confirmed an associative mechanism for A2 via an equilibrium-based pathway (ΔH≠ = (21 ± 1) kJ mol−1; ΔS≠ = (−209 ± 4) J K−1mol−1), with a smaller contribution from a reverse reductive elimination/solvent pathway. The dinuclear complex B2 showed the oxidative addition of MeI only at Rh1(I), which formed a Rh(III)-alkyl, but cleaved the bridged Rh2(I) site, yielding trans-[RhI(PPh3)2(I)(CO)] (5B) as a secondary product. A significantly smaller negative activation entropy [ΔH≠ = (73.0 ± 1.2) kJ mol−1; ΔS≠ = (−21 ± 4) J K−1mol−1] via a more complex/potential interchange mechanism (the contribution of ΔS≠ to the Gibbs free energy of activation, ΔG≠, only ±10%) was inferred, contrary to the entropy-driven oxidative addition of MeI to A2 (the contribution of ΔS≠ to ΔG≠ ± 75%).
Collapse
|
|
2
|
Alexander OT, Venter J. Crystal structure of monocarbonyl(N-nitroso-N-oxido-phenylamine-κ
2
O,O′)(tricyclohexylphosphine-κP)rhodium(I), C25H39N2O3PRh. Z KRIST-NEW CRYST ST 2021. [DOI: 10.1515/ncrs-2021-0218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
C25H39N2O3PRh, triclinic, P21/n (no. 14), a = 13.505(5) Å, b = 14.266(5) Å, c = 13.405(4) Å, β = 91.280(3)°, V = 2574.8(15) Å3, Z = 4, R
gt
(F) = 0.0399, wR
ref
(F
2) = 0.1026, T = 100 K.
Collapse
Affiliation(s)
- Orbett T. Alexander
- Department of Chemistry , University of the Free State , Bloemfontein , 9301 , South Africa
| | - Johan Venter
- Department of Chemistry , University of the Free State , Bloemfontein , 9301 , South Africa
| |
Collapse
|
|
3
|
Elmakki MAE, Alexander OT, Venter GJS, Venter JA, Roodt A. Synthesis and structural determination of [Rh(opo)(CO)(PR 3)] complexes (opo − = 2-oxopyridin-1-olate) and in situ isomeric behavior from preliminary kinetic study of iodomethane oxidative addition. J COORD CHEM 2021. [DOI: 10.1080/00958972.2021.1879385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
| | - Orbett T. Alexander
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| | | | - Johan A. Venter
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| | - Andreas Roodt
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| |
Collapse
|
|
4
|
Mokolokolo PP, Alexander OT, Schutte-Smith M, Brink A, Roodt A. Crystal structure of monocarbonyl[2-((cyclopentylmethylene)amino)-5-methylphenolato-κ 2N,O] (tricyclohexylphosphine)rhodium(I), C 32H 48NO 2PRh. Z KRIST-NEW CRYST ST 2020. [DOI: 10.1515/ncrs-2020-0248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
C32H48NO2PRh, orthorhombic, P212121 (no. 19), a = 26.784(10) Å, b = 8.837(3) Å, c = 12.759(4) Å, V = 3020.0(18) Å3, Z = 4, R
gt(F) = 0.0400, wR
ref(F
2) = 0.0920, T = 100(2) K.
Collapse
Affiliation(s)
- Pennie P. Mokolokolo
- Department of Chemistry , University of the Free State , Bloemfontein 9301, South Africa
| | - Orbett T. Alexander
- Department of Chemistry , University of the Free State , Bloemfontein 9301, South Africa
| | | | - Alice Brink
- Department of Chemistry , University of the Free State , Bloemfontein 9301, South Africa
| | - Andreas Roodt
- Department of Chemistry , University of the Free State , Bloemfontein 9301, South Africa
| |
Collapse
|
|
5
|
Mokolokolo PP, Brink A, Roodt A, Schutte-Smith M. Subtle variation of stereo-electronic effects in rhodium(I) carbonyl Schiff base complexes and their iodomethane oxidative addition kinetics. J COORD CHEM 2020. [DOI: 10.1080/00958972.2020.1809657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Pennie P. Mokolokolo
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| | - Alice Brink
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| | - Andreas Roodt
- Department of Chemistry, University of the Free State, Bloemfontein, South Africa
| | | |
Collapse
|
|
6
|
Warsink S, Riekert Kotze PD, Janse van Rensburg JM(I, Venter JA, Otto S, Botha E, Roodt A. Kinetic‐Mechanistic and Solid‐State Study of the Oxidative Addition and Migratory Insertion of Iodomethane to [Rhodium(
S
,
O
‐
BdiPT
or
N
,
O‐ox
)(CO)(PR
1
R
2
R
3
)] Complexes. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800293] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Stefan Warsink
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
| | - P. D. Riekert Kotze
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
- R&D Division Sasol Technology 1 Klasie Havenga Street 1948 Sasolburg South Africa
| | | | - Johan A. Venter
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
| | - Stefanus Otto
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
- R&D Division Sasol Technology 1 Klasie Havenga Street 1948 Sasolburg South Africa
| | - Ebrahiem Botha
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
| | - Andreas Roodt
- Department of Chemistry University of the Free State PO Box 339 9300 Bloemfontein South Africa
| |
Collapse
|
|
7
|
Drost RM, Koen R, Roodt A, Venter JA. Crystal structure of monocarbonyl( N-nitroso- N-oxido-phenylamine-κ 2
O, O′)(triphenylarsine-κ As)rhodium(I), C 25H 20AsN 2O 3Rh. Z KRIST-NEW CRYST ST 2016. [DOI: 10.1515/ncrs-2015-0158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
C25H20AsN2O3Rh, triclinic, P-1 (no. 1), a = 9.2781(15) Å, b = 10.1405(15) Å, c = 13.303(2) Å, α = 99.789(5)°, β = 107.971(5)°, γ = 94.089(5)°, V = 1162.9(3) Å3, Z = 2, R
gt
(F) = 0.0578, wR
ref
(F
2
) = 0.1833, T = 100(2) K.
Collapse
Affiliation(s)
- Ruben M. Drost
- Department of Chemistry, University of the Free State, Nelson Mandela Ave, Bloemfontein, South Africa
| | - Renier Koen
- Department of Chemistry, University of the Free State, Nelson Mandela Ave, Bloemfontein, South Africa
| | - Andreas Roodt
- Department of Chemistry, University of the Free State, Nelson Mandela Ave, Bloemfontein, South Africa
| | - Johan A. Venter
- Department of Chemistry, University of the Free State, Nelson Mandela Ave, Bloemfontein, South Africa
| |
Collapse
|
|
8
|
Elmakki MA, Koen R, Drost RM, Alexander OT, Venter GJS, Venter JA. Crystal structure of carbonyl(2-oxopyridin-1(2 H)-olato-κ 2
O, O′)(triphenylphosphine-κ P)rhodium(I), C 24H 19NO 3PRh. Z KRIST-NEW CRYST ST 2016. [DOI: 10.1515/ncrs-2015-0266] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
C24H19NO3PRh, triclinic, P1̅ (no. 2), a = 9.1734(16) Å, b = 9.5433(18) Å, c = 12.342(2) Å, α = 92.400(6)°, β = 105.460(5)°, γ = 99.472(5)°, V = 1023 Å3, Z = 2, R
gt
(F) = 0.0236, wR
ref
(F
2
) = 0.0597, T = 100 K.
Collapse
Affiliation(s)
- Mohammed A. Elmakki
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| | - Renier Koen
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| | - Ruben M. Drost
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| | - Orbett T. Alexander
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| | - Gertruida J. S. Venter
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| | - Johan A. Venter
- Department of Chemistry , University of the Free State , P.O. Box 339, Bloemfontein 9300, South Africa
| |
Collapse
|
|
9
|
Warsink S, Venter JA, Roodt A. NHC-amide donor ligands in rhodium complexes: Syntheses and characterisation. J Organomet Chem 2015. [DOI: 10.1016/j.jorganchem.2014.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|