|
1
|
Akpan E, Oladipo SD, Quadri TW, Olasunkanmi LO, Nwanna EE, Omondi B, Ebenso EE. Formamidine-Based Thiuram Disulfides as Efficient Inhibitors of Acid Corrosion of Mild Steel: Electrochemical, Surface, and Density Functional Theory/Monte Carlo Simulation Studies. ACS OMEGA 2022; 7:26076-26091. [PMID: 35936469 PMCID: PMC9352172 DOI: 10.1021/acsomega.2c00985] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 07/08/2022] [Indexed: 05/09/2023]
Abstract
Electrochemical, surface, and density functional theory (DFT)/Monte Carlo (MC) simulation studies were used in investigating the characteristics of N,N'-(disulfanne-1,2-dicarbonothioyl)bis(N,N'-bis(2,6-dimethylphenyl)formimidamide) (DS1), N,N'-(disulfanne-1,2-dicarbonothioyl)bis(N,N'-bis(2,6-diisopropylphenyl)formimidamide) (DS2), N,N'-(disulfanne-1,2-dicarbonothioyl)bis(N,N'-dimesitylformimidamide) (DS3), and N,N'-(disulfanne-1,2-dicarbonothioyl)bis(N,N'-bis(2,6-dichlorophenyl)formimidamide) (DS4) as inhibitors of acid corrosion of mild steel. The inhibitors were found to effectively reduce the rates of steel dissolution at the anode as well as cathodic hydrogen evolution. The order of inhibition efficiencies of studied compounds is DS1 (PDP/LPR/EIS: 98.60/97.98/96.94%) > DS2 (PDP/LPR/EIS: 98.36/96.86/96.90%) > DS3 (PDP/LPR/EIS: 94.66/87.44/94.30%) > DS4 (PDP/LPR/EIS: 83.57/77.02/75.17%) at 1.00 mM, and the overall efficiencies appeared to depend on the molecular and electronic structures of the compounds. The compounds offered high resistance to charge transfer across the electrode/electrolyte system by forming adsorbed film whose resistance increased with an increase in concentration. Findings suggested that the adsorption process involved combined chemisorption and physisorption. DFT calculations and MC simulations provided theoretical justifications for the experimental results.
Collapse
Affiliation(s)
- Ekemini
D. Akpan
- College
of Science, Engineering and Technology University of South Africa, Johannesburg 1710, South Africa
| | - Segun D. Oladipo
- School
of Chemistry and Physics, University of
Kwazulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
- Department
of Chemical Sciences, Olabisi Onabanjo University, P.M.B. 2002, Ago-Iwoye 120107, Nigeria
| | - Taiwo W. Quadri
- Department
of Chemistry, School of Physical and Chemical Sciences, Faculty of
Natural and Agricultural Sciences, North-West
University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735, South Africa
| | - Lukman O. Olasunkanmi
- Department
of Chemistry, Faculty of Science, Obafemi
Awolowo University, Ile-Ife 220005, Nigeria
- Department
of Chemical Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein Campus, Johannesburg 2028, South Africa
| | - Esther E. Nwanna
- Department
of Biochemistry, Federal University of Technology, P.M.B 704, Akure 340110, Nigeria
| | - Bernard Omondi
- School
of Chemistry and Physics, University of
Kwazulu-Natal, Pietermaritzburg Campus, Private Bag X01, Scottsville 3209, South
Africa
| | - Eno E. Ebenso
- College
of Science, Engineering and Technology University of South Africa, Johannesburg 1710, South Africa
| |
Collapse
|
|
2
|
Formamidine-based thiuram disulfides: Synthesis, structural characterization, biological studies, and preliminary cheminformatics evaluation. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128553] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
|
4
|
Fontenot PR, Wang B, Chen Y, Donahue JP. Crystal structure of tetra-iso-butyl-thiuram di-sulfide. Acta Crystallogr E Crystallogr Commun 2017; 73:1764-1769. [PMID: 29152369 PMCID: PMC5683509 DOI: 10.1107/s2056989017015158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 10/17/2017] [Indexed: 11/24/2022]
Abstract
Tetra-kis(2-methyl-prop-yl)thio-per-oxy-dicarbonic di-amide, or tetra-iso-butyl-thiuram di-sulfide, C18H36N2S4, crystallizes in a general position in the triclinic space group P-1 but shows pseudo-C2 symmetry about the di-sulfide bond. The C-S-S-C torsion angle [-85.81 (2)°] and the dihedral angle between the two NCS2 mean planes [85.91 (5)°] are within the range observed for this compound type. Multiple intra- and inter-molecular S⋯H-C close contacts appear to play a role in assisting the specific conformation of the pendant isobutyl groups and the packing arrangement of mol-ecules within the cell. Tetra-iso-butyl-thiuram di-sulfide mol-ecules of one optical configuration form sheets in the plane of the a and b axes. Inversion centers exist between adjoining sheets, which stack along the c axis and alternate in the handedness of their constituent mol-ecules.
Collapse
Affiliation(s)
- Patricia R. Fontenot
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans, Louisiana 70118-5698, USA
| | - Bo Wang
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans, Louisiana 70118-5698, USA
| | - Yueli Chen
- Department of Chemistry, SUNY Stony Brook, 100 Nicolls Road, Stony Brook, New York 11790-3400, USA
| | - James P. Donahue
- Department of Chemistry, Tulane University, 6400 Freret Street, New Orleans, Louisiana 70118-5698, USA
| |
Collapse
|
|
5
|
Srinivasan N, Thirumaran S, Selvanayagam S. Bis(1,2,3,4-tetra-hydro-quinoline-1-thio-carbon-yl) disulfide. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o3446. [PMID: 23476260 PMCID: PMC3589024 DOI: 10.1107/s1600536812047320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 11/17/2012] [Indexed: 11/11/2022]
Abstract
In the title compound, C20H20N2S4, the N-containing six-membered rings of the two tetra-hydro-quinoline moieties adopt half-chair conformations. Intra-molecular C-H⋯S hydrogen bonding stabilizes the mol-ecular structure. In the crystal, mol-ecules associate via weak C-H⋯π inter-actions.
Collapse
Affiliation(s)
- N. Srinivasan
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, India
| | - S. Thirumaran
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, India
| | - S. Selvanayagam
- Department of Physics, Kalasalingam University, Krishnankoil 626 126, India
| |
Collapse
|