Next Article in Journal
Metabolic Profiling and Potential Taste Biomarkers of Two Rambutans during Maturation
Previous Article in Journal
Folic Acid Functionalized Diallyl Trisulfide–Solid Lipid Nanoparticles for Targeting Triple Negative Breast Cancer
Previous Article in Special Issue
Metal-Free Aerobic C–N Bond Formation of Styrene and Arylamines via Photoactivated Electron Donor–Acceptor Complexation
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Molecules
Volume 28
Issue 3
10.3390/molecules28031397
molecules-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Communication

Paired Electrolysis Enabled Cyanation of Diaryl Diselenides with KSCN Leading to Aryl Selenocyanates

by
Wei-Bao He
1,
Luo-Lin Tang
1,
Jun Jiang
2,
Xiao Li
2,
Xinhua Xu
1,*,
Tian-Bao Yang
3 and
Wei-Min He
2,*
1
College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
2
School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
3
National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass, Nanjing Forestry University, Nanjing 210037, China
*
Authors to whom correspondence should be addressed.
Molecules 2023, 28(3), 1397; https://doi.org/10.3390/molecules28031397
Submission received: 25 December 2022 / Revised: 17 January 2023 / Accepted: 24 January 2023 / Published: 1 February 2023
(This article belongs to the Special Issue Catalysis of Radical Reactions: Recent Progress and Emerging Fields)
Browse Figures
Review Reports Versions Notes

Abstract

:
The first example of paired electrolysis-enabled cyanation of diaryl diselenides, with KSCN as the green cyanating agent, has been developed. A broad range of aryl selenocyanates can be efficiently synthesized under chemical-oxidant- and additive-free, energy-saving and mild conditions.

1. Introduction

Selenium-containing compounds have attracted the interest of synthetic organic chemists during the past few years, due to the fact that organic selenium compounds are widely found in pharmaceutical, agrochemical molecules, fluorescent molecular probes and promising biomaterials [1,2,3]. Among various selenium-containing compounds, aryl selenocyanates (ArSeCN) represent a fundamentally important class of heteroatom-containing compounds, and have gained a great deal of attention. They not only display a wide range of biological and pharmacological activities but also serve as highly versatile synthetic intermediates for the synthesis of various organic selenium compounds in organic synthesis [4,5,6,7,8,9]. As a consequence, considerable efforts have been devoted to constructing such molecules, and a series of synthetic protocols have been developed [10,11]. The traditional methods can be divided into two categories according to the reaction substrates (Scheme 1a): (1) the reaction of phenylselenol or its derivative (PhSeH and PhSeCl) with a cyanating agent [12,13]; and (2) the reaction of various selenium-free aryl substrates with in-situ-generated selenocyanating agent (selenium powder/ trimethylsilyl cyanide, [14,15] selenium dioxide/malononitrile [16]) or the harmful potassium selenocyanate (KSeCN) [17,18,19,20,21]. Despite their achievements, the above-mentioned strategies generally require toxic and environmentally hazardous cyano sources; therefore, developing eco-friendly and more practical approaches for constructing such molecules from low-cost and non-toxic cyano sources are still highly desirable.
Thiocyanate salt is one of the most widely used inorganic sulfosalts, and has been considered as an attractive cyano source, given its non-toxicity, low cost and abundance [22]. Both thermal [23,24,25,26,27] and photocatalytic cyanation [28,29] with MSCN have been reported in recent years (Scheme 1b). Very recently, Bhat et al. reported the visible-light-induced Rhodamine-6G-catalyzed cyanation of diphenyl diselenide and NaSCN by using pure oxygen as the oxidant and K2CO3 as the additive (Scheme 1c) [30]. However, all the above-mentioned reactions require chemical oxidizing agents, photocatalysts and stoichiometric amounts of additives.
Organic electrochemical synthesis, as an environmentally friendly synthetic strategy, has emerged as a powerful tool in organic synthetic chemistry [31,32,33,34]. In comparison with the traditional methods that often proceed at strong oxidative or reductive conditions with elevated temperature or pressure in the presence of chemical oxidizing agents or reducing agents, electrochemical reactions are usually carried out under milder conditions by precisely varying the applied electrode potential. Therefore, electrosynthesis is usually compatible with highly functionalized substrates and has displayed great potential in both synthetic and bioconjugation chemistry [35,36,37,38,39,40,41]. In recent years, electrochemical cyanation with various cyanating agents (trimethylsilyl cyanide [42,43,44,45,46], cyanobenziodoxolone [47], AIBN [48], tosyl cyanide [49] and 4-cyanopyridine [50]) have been used to construct the cyanated products. In contradistinction, to the best of our knowledge, electrochemical cyanation with thiocyanate salts has never been reported. Paired electrosynthesis utilizes traceless electrons as the redox reagent, maximizing the congeniality through performing anodic oxidation and cathodic reduction simultaneously, and displays pronounced advances in energy efficiency and time efficiency [51,52]. In recent years, a series of paired electrolysis strategies have been developed for the sustainable synthesis of important fine chemicals [53,54,55,56,57,58]. Considering the importance of ArSeCN, and with our continued interest in developing green synthetic reactions [59,60,61,62,63,64,65,66], we herein report the paired electrolysis-enabled cyanation of diaryl diselenides and KSCN for synthesizing ArSeCN under chemical oxidant-free and mild conditions (Scheme 1d). To the best of our knowledge, this is the first example of the paired electro-synthesis of cyano-containing compounds from KSCN under electrochemical conditions.

2. Results and Discussion

The electrochemical selenocyanation of PhSeSePh (1a) with KSCN (2a) was selected as a model reaction for probing various reaction parameters (Table 1). Using LiBF4 as the supporting electrolyte and MeCN as the sole solvent, the target phenyl selenocyanate 3a could be obtained in 83% GC yield under 15 mA constant current in an undivided cell equipped with a graphite plate anode and platinum plate cathode (Table 1, entry 1). Changing the graphite plate anode to a platinum plate anode led to the formation of product 3a in 51% GC yield (entry 2). Performing the model reaction with graphite plate anode/copper plate anode, graphite plate anode/copper plate anode or graphite plate anode/copper plate anode resulted in the generation of phenyl selenocyanate 3a in 60–17% GC yields (entries 3–5). However, no desired product was observed for the template reaction using nickel plate or magnesium plate as the anode instead of platinum plate (entries 6 and 7). Only a trace amount of product 3a was observed when LiBF4 was replaced by other lithium salts (entry 8). Conducting the reaction with tetrafluoroborate salts as the supporting electrolyte gave a trace amount of product 3a (entry 9). The solvent effect imposed a key effect on the reaction efficiency. When the reaction was carried out in DMF, 27% GC yield of 3a was obtained (entry 10). A trace amount of 3a was detected by using EtOH, DCE, DMSO, THF or sole acetone as the solvent (entry 11). No reaction was observed under 10 mA constant current electrolysis conditions (entry 12). Increasing the constant current from 15 mA to 20 mA gave a 65% yield of 3a (entry 13). The omission of LiBF4 led to no transformation (entry 14).
Having established the optimized conditions (Table 1, entry 1), the substrate applicability of this electrochemical cyanation was investigated (Scheme 2). Various substituted diphenyl diselenides possessing electron-neutral (H and Ph), electron-donating (Me, tBu, OMe, OBn, OCF3 and SMe) or electron-withdrawing groups (F, Cl, Br, CF3 and CO2Me) at the para-position of the phenyl ring successfully entered this process, leading to the desired phenyl selenocyanates (3a–3m) in good yields. Both ortho- and meta-substituted diphenyl diselenides were suitable for this transformation, delivering the corresponding products (3n–3q) in 62–73% yields. The sterically bulky 1,2-dimesityldiselane participated in this reaction smoothly and gave the product 3r in 74% yield. Diselenides substrates with fused aromatic rings, including naphthalene (1s and 1t), 2,3-dihydrobenzo[b][1,4]dioxine (1u), quinoline (1v), indole (1w) and benzofuran (1x) could also be transformed into the desired products (3s–3x) in good yields.
To acquire insight into the mechanism of the cyanation reaction, a series of mechanistic studies were carried out. First, the radical scavenger experiment was conducted. The electrocatalytic reaction of diphenyl diselenide and KSeCN was fully suppressed in the presence of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and butylated hydroxytoluene (BHT) (Scheme 3a). In addition, the diphenylethylene-CN adduct (4a) was detected by GC−MS. These results suggested that the cyano radical was the critical radical intermediate in the present transformation (Scheme 3b). The phenylselanethiol (4b) was detected in the acidified reaction mixture by GC−MS, indicating that the phenylselanethiol anion was generated in the current cyanation reaction (Scheme 4c). The power on/off experimental results indicated that continuous electric current was necessary to drive this cyanation reaction, thus excluding the radical chain mechanism.
To further understand the mechanism of the electrocatalytic process, cyclic voltammetry experiments (CV) were conducted (Figure 1, for details, see Supplementary Materials). The CV curve of diphenyl diselenide presented an onset potential at 1.05 V and an oxidative potential at 1.54 V. Both lower onset potential (0.53 V) and lower oxidative potential (0.98 V) of KSCN were obtained. The mixture of diphenyl diselenide and KSCN had the same onset potential and the same oxidative potential as that of KSCN. These results suggested that the oxidation of KSCN might occur preferentially at the surface of the anode.
On the basis of the above-mentioned results and the previous literature, [27,45,61] a plausible mechanism for the electrochemical cyanation was depicted in Scheme 4. Firstly, KSCN (2) underwent one-electron oxidation at the surface of the graphite anode to generate a thiocyanate radical (SCN−), which attacked the Se atom of PhSeSePh (1) to form the benzenesulfinoselenoyl cyanide intermediate (A). The unstable intermediate A easily underwent bond cleavage to produce the desired product PhSeCN (3) and phenylselanethiol radical B, followed by one-electron reduction to form phenylselanethiol anion C.

3. Materials and Methods

3.1. General Considerations

Unless otherwise noted, all reagents were obtained from commercial suppliers and used without further purification. The instrument used for electrolysis was a dual display potentiostat (DJS-292B) (made in China). Graphite electrode was 15 mm × 10 mm × 2 mm and platinum electrode was 15 mm × 10 mm × 0.1 mm. The instrument used for cyclic voltammetry was a CHI 660E potentiostat, and the conditions were as follows: a glassy carbon disk working electrode (diameter, 2 mm), Pt disk and Ag/AgCl (0.1 M in CH3CN) as counter and reference electrode. Thin-layer chromatography (TLC) employed glass 0.25 mm silica gel plates. Flash chromatography columns were packed with 200–300 mesh silica gel. 1H NMR spectra were recorded at 500 MHz and 13C NMR spectra were recorded at 126 MHz by using a Bruker Avance 500 spectrometer. Chemical shifts were calibrated using residual undertreated solvent as an internal reference (1H NMR: CDCl3 7.26 ppm, 13C NMR: CDCl3 77.0 ppm), the chemical shifts (δ) were expressed in ppm and J values were given in Hz. HRMS were performed on a spectrometer operating on ESI-TOF.

3.2. Typical Procedure for the Synthesis of 3

In an undivided flask (10 mL) equipped with a stir bar, diphenyl diselenide (0.2 mmol), KSCN (0.5 mmol), LiBF4 (0.1 mmol) and MeCN (6 mL) were added. The flask was equipped with graphite (15 mm × 10 mm × 2 mm) as the anode and a platinum electrode (15 mm × 10 mm × 0.1 mm) as the cathode. The reaction mixture was stirred and electrolyzed at a constant current of 15 mA under room temperature for 9 h. After completion, the solvent was concentrated under reduced pressure, and the pure products 3 were obtained by flash chromatography on silica gel.

4. Conclusions

In conclusion, we have developed the first example of electrochemical cyanation of diaryl diselenides with KSCN as a cyanating agent through a paired one-electron oxidation and reduction processes. The importance and advantages of the present strategy is three-fold: (a) this work not only revealed a novel route for producing various aryl selenocyanates but also offered mechanistic insights into this reaction, which may suggest new processes for the construction of Se-CN bonds. (b) The present procedure was free of transition metals, chemical oxidants and poisonous reagents, making it more environmentally friendly. (c) The reaction proceeded with good functional-group compatibility, which should contribute to the practical synthesis of complex molecules. Given the natural abundance of inexpensive starting materials, good functional-group tolerance, good yields and simple operation procedures, the developed reaction is expected to be widely applied in synthetic chemistry and the pharmaceutical industry.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules28031397/s1, General experimental procedures for Compound 3; Cyclic voltammetry experiment; Figure S1: Cyclic voltammetry experiment; Characterization data of products 3a–3x; 1H, 13C spectra of the products.

Author Contributions

W.-M.H. and X.X. supervised the project and wrote the manuscript; W.-B.H., L.-L.T., X.L., T.-B.Y. and J.J. performed the experiments, analyzed data and discussed with W.-M.H. and X.X. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Scientific Research Fund of Hunan Provincial Education Department (22B0435).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

Sample Availability

Samples of the compounds are available from the authors.

References

  1. Ali, W.; Álvarez-Pérez, M.; Marć, M.A.; Salardón-Jiménez, N.; Handzlik, J.; Domínguez-Álvarez, E. The Anticancer and Chemopreventive Activity of Selenocyanate-Containing Compounds. Curr. Pharmacol. Rep. 2018, 4, 468–481. [Google Scholar] [CrossRef]
  2. An, B.; Wang, B.; Hu, J.; Xu, S.; Huang, L.; Li, X.; Chan, A.S.C. Synthesis and Biological Evaluation of Selenium-Containing 4-Anilinoquinazoline Derivatives as Novel Antimitotic Agents. J. Med. Chem. 2018, 61, 2571–2588. [Google Scholar] [CrossRef]
  3. Mukherjee, N.; Kundu, D.; Ranu, B.C. Copper-Silver Dual Catalyzed Decyanative C–Se Cross-Coupling. Adv. Synth. Catal. 2017, 359, 329–338. [Google Scholar] [CrossRef]
  4. Kalaramna, P.; Bhatt, D.; Sharma, H.; Goswami, A. An Expeditious and Environmentally-Benign Approach to 2-Aryl/Heteroaryl Selenopyridines via Ruthenium Catalyzed [2+2+2] Cycloadditions. Eur. J. Org. Chem. 2019, 2019, 4694–4700. [Google Scholar] [CrossRef]
  5. Yang, L.; Tian, Z.-Y.; Zhang, C.-P. Transition-Metal-Free Selective Synthesis of (Z)-1,2-Diarylthio-1-arylalkenes, (2-Arylethene-1,1,2-triyl)tris(arylsulfane)s and Alkynyl Sulfides from Thiocyanates and Terminal Arylalkynes. ChemistrySelect 2019, 4, 311–315. [Google Scholar] [CrossRef]
  6. Cao, Y.; Jiang, L.; Yi, W. Synthesis of Monofluoromethyl Selenoethers of Aryl and Alkyl from Organoselenocyanate via One-Pot Reaction. Adv. Synth. Catal. 2019, 361, 4360–4368. [Google Scholar] [CrossRef]
  7. Liu, X.-S.; Li, M.; Dong, K.; Peng, S.; Liu, L. Highly Stereoselective Synthesis of Tetrasubstituted Vinyl Selenides via Rhodium-Catalyzed [1,4]-Acyl Migration of Selenoesters and Diazo Compounds. Org. Lett. 2022, 24, 2175–2180. [Google Scholar] [CrossRef]
  8. Jana, S.; Koenigs, R.M. Rhodium-Catalyzed Carbene Transfer Reactions for Sigmatropic Rearrangement Reactions of Selenium Ylides. Org. Lett. 2019, 21, 3653–3657. [Google Scholar] [CrossRef]
  9. Lin, X.; Tan, Z.; Yang, W.; Yang, W.; Liu, X.; Feng, X. Chiral Cobalt(II) Complex Catalyzed Asymmetric [2,3]-Sigmatropic Rearrangement of Allylic Selenides with α-Diazo Pyrazoleamides. CCS Chem. 2020, 3, 1423–1433. [Google Scholar] [CrossRef]
  10. Gao, M.; Vuagnat, M.; Chen, M.-Y.; Pannecoucke, X.; Jubault, P.; Besset, T. Design and Use of Electrophilic Thiocyanating and Selenocyanating Reagents: An Interesting Trend for the Construction of SCN- and SeCN-Containing Compounds. Chem.-Eur. J. 2021, 27, 6145–6160. [Google Scholar] [CrossRef]
  11. Karmaker, P.G.; Huo, F. Organic Selenocyanates: Rapid Advancements and Applicationsin the Field of Organic Chemistry. Asian J. Org. Chem. 2022, 11, e202200226. [Google Scholar] [CrossRef]
  12. Wang, Z.-H.; Ji, X.-M.; Hu, M.-L.; Tang, R.-Y. Nitromethane as a cyanating reagent for the synthesis of thiocyanates. Tetrahedron Lett. 2015, 56, 5067–5070. [Google Scholar] [CrossRef]
  13. Frei, R.; Courant, T.; Wodrich, M.D.; Waser, J. General and Practical Formation of Thiocyanates from Thiols. Chem.-Eur. J. 2015, 21, 2662–2668. [Google Scholar] [CrossRef] [PubMed]
  14. Feng, C.; Peng, Y.; Ding, G.; Li, X.; Cui, C.; Yan, Y. Catalyst and additive-free regioselective oxidative C–H thio/selenocyanation of arenes and heteroarenes with elemental sulfur/selenium and TMSCN. Chem. Commun. 2018, 54, 13367–13370. [Google Scholar] [CrossRef] [PubMed]
  15. Zhang, X.; Huang, X.-B.; Zhou, Y.-B.; Liu, M.-C.; Wu, H.-Y. Metal-Free Synthesis of Aryl Selenocyanates and Selenaheterocycles with Elemental Selenium. Chem.-Eur. J. 2021, 27, 944–948. [Google Scholar] [CrossRef] [PubMed]
  16. Redon, S.; Kosso, A.R.O.; Broggi, J.; Vanelle, P. Metal-Free ipso-Selenocyanation of Arylboronic Acids Using Malononitrile and Selenium Dioxide. Synthesis 2019, 51, 3758–3764. [Google Scholar] [CrossRef]
  17. Nikolaienko, P.; Rueping, M. Trifluoromethylselenolation of Aryldiazonium Salts: A Mild and Convenient Copper-Catalyzed Procedure for the Introduction of the SeCF3 Group. Chem.-Eur. J. 2016, 22, 2620–2623. [Google Scholar] [CrossRef]
  18. Guan, Y.; Townsend, S.D. Metal-Free Synthesis of Unsymmetrical Organoselenides and Selenoglycosides. Org. Lett. 2017, 19, 5252–5255. [Google Scholar] [CrossRef]
  19. He, D.; Yao, J.; Ma, B.; Wei, J.; Hao, G.; Tuo, X.; Guo, S.; Fu, Z.; Cai, H. An electrochemical method for deborylative seleno/thiocyanation of arylboronic acids under catalyst- and oxidant-free conditions. Green Chem. 2020, 22, 1559–1564. [Google Scholar] [CrossRef]
  20. Zhang, J.; Wang, H.; Chen, Y.; Xie, H.; Ding, C.; Tan, J.; Xu, K. Electrochemical synthesis of selenocyanated imidazo[1,5-a]quinolines under metal catalyst- and chemical oxidant-free conditions. Chin. Chem. Lett. 2020, 31, 1576–1579. [Google Scholar] [CrossRef]
  21. Xiao, J.-A.; Liang, J.-S.; Zhang, H.; Meng, R.-F.; Su, W.; Lin, C.; Cui, J.-G.; Huang, Y.-M. Solid-State Direct Electrophilic Selenocyanation of (Hetero)Arenes using Mechanochemistry. Eur. J. Org. Chem. 2022, 2022, e202200902. [Google Scholar] [CrossRef]
  22. Castanheiro, T.; Suffert, J.; Donnard, M.; Gulea, M. Recent advances in the chemistry of organic thiocyanates. Chem. Soc. Rev. 2016, 45, 494–505. [Google Scholar] [CrossRef] [PubMed]
  23. Wagner, A.; Ofial, A.R. Potassium Thiocyanate as Source of Cyanide for the Oxidative α-Cyanation of Tertiary Amines. J. Org. Chem. 2015, 80, 2848–2854. [Google Scholar] [CrossRef]
  24. Huang, Y.; Yu, Y.; Zhu, Z.; Zhu, C.; Cen, J.; Li, X.; Wu, W.; Jiang, H. Copper-Catalyzed Cyanation of N-Tosylhydrazones with Thiocyanate Salt as the “CN” Source. J. Org. Chem. 2017, 82, 7621–7627. [Google Scholar] [CrossRef] [PubMed]
  25. Sardarian, A.R.; Inaloo, I.D.; Modarresi-Alam, A.R.; Kleinpeter, E.; Schilde, U. Metal-Free Regioselective Monocyanation of Hydroxy-, Alkoxy-, and Benzyloxyarenes by Potassium Thiocyanate and Silica Sulfuric Acid as a Cyanating Agent. J. Org. Chem. 2019, 84, 1748–1756. [Google Scholar] [CrossRef]
  26. Wang, J.; Sun, B.; Zhang, L.; Xu, T.; Xie, Y.; Jin, C. Transition-metal-free direct C-3 cyanation of quinoxalin-2(1H)-ones with ammonium thiocyanate as the “CN” source. Org. Chem. Front. 2020, 7, 113–118. [Google Scholar] [CrossRef]
  27. Yang, Q.; Yan, X.-T.; Feng, C.-T.; Chen, D.-X.; Yan, Z.-Z.; Xu, K. Tandem Strecker/C(sp3)–H amination reactions for the construction of cyanide-functionalized imidazo[1,5-a]pyridines with NH4SCN as a cyanating agent. Org. Chem. Front. 2021, 8, 6384–6389. [Google Scholar] [CrossRef]
  28. Guo, W.; Tan, W.; Zhao, M.; Zheng, L.; Tao, K.; Chen, D.; Fan, X. Direct Photocatalytic S–H Bond Cyanation with Green “CN” Source. J. Org. Chem. 2018, 83, 6580–6588. [Google Scholar] [CrossRef]
  29. Yi, B.; Yan, N.; Yi, N.; Xie, Y.; Wen, X.; Au, C.-T.; Lan, D. Oxidative cyanation of N-aryltetrahydroisoquinoline induced by visible light for the synthesis of α-aminonitrile using potassium thiocyanate as a “CN” agent. RSC Adv. 2019, 9, 29721–29725. [Google Scholar] [CrossRef]
  30. Dharpure, P.D.; Behera, M.; Khade, V.V.; Thube, A.S.; Bhat, R.G. Direct Access to Thiocyano-Thioesters from Cyclic Thioacetals via Photoredox Catalysis: An Introduction of Two Functional Groups in One Pot. Org. Lett. 2022, 24, 6919–6924. [Google Scholar] [CrossRef]
  31. Chen, N.; Xu, H.-C. Electrochemically Driven Radical Reactions: From Direct Electrolysis to Molecular Catalysis. Chem. Rec. 2021, 21, 2306–2319. [Google Scholar] [CrossRef] [PubMed]
  32. Ma, C.; Fang, P.; Liu, Z.-R.; Xu, S.-S.; Xu, K.; Cheng, X.; Lei, A.; Xu, H.-C.; Zeng, C.; Mei, T.-S. Recent advances in organic electrosynthesis employing transition metal complexes as electrocatalysts. Sci. Bull. 2021, 66, 2412–2429. [Google Scholar] [CrossRef]
  33. Sun, K.; Xiao, F.; Yu, B.; He, W.-M. Photo-/electrocatalytic functionalization of quinoxalin-2(1H)-ones. Chin. J. Catal. 2021, 42, 1921–1943. [Google Scholar] [CrossRef]
  34. Zhou, H.-Y.; Tan, H.-T.; He, W.-M. Organic Electrochemistry-current transfer future. Chin. J. Catal. 2023, 46, 4–10. [Google Scholar]
  35. Wu, H.; Yu, X.; Cao, Z. Electrochemical Multicomponent Synthesis of α-Ketoamides from α-Oxocarboxylic Acids, Isocyanides and Water. Chin. J. Org. Chem. 2021, 41, 4712–4717. [Google Scholar] [CrossRef]
  36. Xu, H.; Meng, X.; Zheng, Y.; Luo, J.; Huang, S. Electrochemical Annulations of o-Alkynylanilines for Synthesis of 3-Iodoindoles. Chin. J. Org. Chem. 2021, 41, 4696–4703. [Google Scholar] [CrossRef]
  37. Wu, Y.; Chen, J.-Y.; Liao, H.-R.; Shu, X.-R.; Duan, L.-L.; Yang, X.-F.; He, W.-M. Electrochemical transient iodination and coupling for selenylated 4-anilinocoumarin synthesis. Green Synth. Catal. 2021, 2, 233–236. [Google Scholar] [CrossRef]
  38. Chen, J.-Y.; Wu, H.-Y.; Gui, Q.-W.; Yan, S.-S.; Deng, J.; Lin, Y.-W.; Cao, Z.; He, W.-M. Sustainable Electrochemical Cross-Dehydrogenative Coupling of 4-Quinolones and Diorganyl Diselenides. Chin. J. Catal. 2021, 42, 1445–1450. [Google Scholar] [CrossRef]
  39. Wu, Z.-L.; Chen, J.-Y.; Tian, X.-Z.; Ouyang, W.-T.; Zhang, Z.-T.; He, W.-M. Electrochemical regioselective synthesis of N-substituted/unsubstituted 4-selanylisoquinolin-1(2H)-ones. Chin. Chem. Lett. 2022, 33, 1501–1504. [Google Scholar] [CrossRef]
  40. Ding, L.; Niu, K.; Liu, Y.; Wang, Q. Electro-reductive C-H cyanoalkylation of quinoxalin-2(1H)-ones. Chin. Chem. Lett. 2022, 33, 4057–4060. [Google Scholar] [CrossRef]
  41. Lu, Y.-H.; Zhang, Z.-T.; Wu, H.-Y.; Zhou, M.-H.; Song, H.-Y.; Ji, H.-T.; Jiang, J.; Chen, J.-Y.; He, W.-M. TBAI/H2O-cooperative electrocatalytic decarboxylation coupling-annulation of quinoxalin-2(1H)-ones with N-arylglycines. Chin. Chem. Lett. 2023, 34, 108036. [Google Scholar] [CrossRef]
  42. Li, L.; Hou, Z.-W.; Li, P.; Wang, L. Site-Selective Electrochemical C–H Cyanation of Indoles. Org. Lett. 2021, 23, 5983–5987. [Google Scholar] [CrossRef] [PubMed]
  43. Jiang, C.; Zhu, Y.; Li, H.; Liu, P.; Sun, P. Direct Cyanation of Thiophenols or Thiols to Access Thiocyanates under Electrochemical Conditions. J. Org. Chem. 2022, 87, 10026–10033. [Google Scholar] [CrossRef] [PubMed]
  44. Cui, T.; Zhan, Y.; Dai, C.; Lin, J.; Liu, P.; Sun, P. Electrochemical Oxidative Regioselective C–H Cyanation of Imidazo[1,2-a]pyridines. J. Org. Chem. 2021, 86, 15897–15905. [Google Scholar] [CrossRef]
  45. Zhan, Y.; Li, Y.; Tong, J.; Liu, P.; Sun, P. Electrochemical Oxidative C−H Cyanation of Quinoxalin-2(1H)-ones with TMSCN. Eur. J. Org. Chem. 2021, 2021, 2193–2197. [Google Scholar] [CrossRef]
  46. Gao, J.; Weng, X.; Ma, C.; Xu, X.; Fang, P.; Mei, T. Electrochemical 2,2,6,6-tetramethylpiperidinyl-N-oxyl (TEMPO)-Mediated α-Cyanation and Phosphonylation of Cyclic Amines with Metal-Free Conditions. Chin. J. Org. Chem. 2021, 41, 3223–3234. [Google Scholar] [CrossRef]
  47. Kong, X.; Chen, X.; Chen, Y.; Cao, Z.-Y. Scalable Electrocatalytic Intermolecular Acylcyanation and Aminocyanation of Alkenes. J. Org. Chem. 2022, 87, 7013–7021. [Google Scholar] [CrossRef]
  48. Gui, Q.-W.; Xiong, Z.-Y.; Teng, F.; Cai, T.-C.; Li, Q.; Hu, W.; Wang, X.; Yu, J.; Liu, X. Electrochemically promoted oxidative α-cyanation of tertiary and secondary amines using cheap AIBN. Org. Biomol. Chem. 2021, 19, 8254–8258. [Google Scholar] [CrossRef]
  49. Kong, X.; Wang, Y.; Chen, Y.; Chen, X.; Lin, L.; Cao, Z.-Y. Cyanation and cyanomethylation of trimethylammonium salts via electrochemical cleavage of C–N bonds. Org. Chem. Front. 2022, 9, 1288–1294. [Google Scholar] [CrossRef]
  50. Kumar, G.S.; Shinde, P.S.; Chen, H.; Muralirajan, K.; Kancherla, R.; Rueping, M. Paired Electrolysis for Decarboxylative Cyanation: 4-CN-Pyridine, a Versatile Nitrile Source. Org. Lett. 2022, 24, 6357–6363. [Google Scholar] [CrossRef]
  51. Zhang, W.; Hong, N.; Song, L.; Fu, N. Reaching the Full Potential of Electroorganic Synthesis by Paired Electrolysis. Chem. Rec. 2021, 21, 2574–2584. [Google Scholar] [CrossRef]
  52. Marken, F.; Cresswell, A.J.; Bull, S.D. Recent Advances in Paired Electrosynthesis. Chem. Rec. 2021, 21, 2585–2600. [Google Scholar] [CrossRef] [PubMed]
  53. Liu, D.; Liu, Z.-R.; Ma, C.; Jiao, K.-J.; Sun, B.; Wei, L.; Lefranc, J.; Herbert, S.; Mei, T.-S. Nickel-Catalyzed N-Arylation of NH-Sulfoximines with Aryl Halides via Paired Electrolysis. Angew. Chem. Int. Ed. 2021, 60, 9444–9449. [Google Scholar] [CrossRef] [PubMed]
  54. Ma, Y.; Hong, J.; Yao, X.; Liu, C.; Zhang, L.; Fu, Y.; Sun, M.; Cheng, R.; Li, Z.; Ye, J. Aminomethylation of Aryl Bromides by Nickel-Catalyzed Electrochemical Redox Neutral Cross Coupling. Org. Lett. 2021, 23, 9387–9392. [Google Scholar] [CrossRef] [PubMed]
  55. Zou, Z.; Li, H.; Huang, M.; Zhang, W.; Zhi, S.; Wang, Y.; Pan, Y. Electrochemical-Promoted Nickel-Catalyzed Oxidative Fluoroalkylation of Aryl Iodides. Org. Lett. 2021, 23, 8252–8256. [Google Scholar] [CrossRef] [PubMed]
  56. Kuciński, K.; Simon, H.; Ackermann, L. Rhoda-Electrocatalyzed C−H Methylation and Paired Electrocatalyzed C−H Ethylation and Propylation. Chem.-Eur. J. 2022, 28, e202103837. [Google Scholar] [CrossRef]
  57. Wang, Z.-H.; Wei, L.; Jiao, K.-J.; Ma, C.; Mei, T.-S. Nickel-catalyzed decarboxylative cross-coupling of indole-3-acetic acids with aryl bromides by convergent paired electrolysis. Chem. Commun. 2022, 58, 8202–8205. [Google Scholar] [CrossRef]
  58. Ouyang, W.-T.; Xiao, F.; Ou, L.-J.; He, W.-M. Green Photocatalytic Syntheses Using Water as Solvent/Hydrogen Source/Oxygen Source. Curr. Opin. Green Sust. 2023, 41, 100760. [Google Scholar] [CrossRef]
  59. Chen, J.-Y.; Li, H.-X.; Mu, S.-Y.; Song, H.-Y.; Wu, Z.-L.; Yang, T.-B.; Jiang, J.; He, W.-M. Electrocatalytic three-component synthesis of 4-halopyrazoles with sodium halide as the halogen source. Org. Biomol. Chem. 2022, 20, 8501–8505. [Google Scholar] [CrossRef]
  60. Gui, Q.-W.; Teng, F.; Yu, P.; Wu, Y.-F.; Nong, Z.-B.; Yang, L.-X.; Chen, X.; Yang, T.-B.; He, W.-M. Visible light-induced Z-scheme V2O5/g-C3N4 heterojunction catalyzed cascade reaction of unactivated alkenes. Chin. J. Catal. 2023, 44, 111–116. [Google Scholar] [CrossRef]
  61. Li, H.; Chen, P.; Wu, Z.; Lu, Y.; Peng, J.; Chen, J.; He, W. Electrochemical Oxidative Cross-Dehydrogenative Coupling of Five-Membered Aromatic Heterocycles with NH4SCN. Chin. J. Org. Chem. 2022, 42, 3398–3404. [Google Scholar] [CrossRef]
  62. Yi, R.; He, W. Visible-Light-Induced Radical Arylation Reactions via Electron Donor-Acceptor Complex. Chin. J. Org. Chem. 2022, 42, 2590–2592. [Google Scholar] [CrossRef]
  63. Yang, D.; Yan, Q.; Zhu, E.; Lv, J.; He, W.-M. Carbon-sulfur bond formation via photochemical strategies: An efficient method for the synthesis of sulfur-containing compounds. Chin. Chem. Lett. 2022, 33, 1798–1816. [Google Scholar] [CrossRef]
  64. He, W.-B.; Zhao, S.-J.; Chen, J.-Y.; Jiang, J.; Chen, X.; Xu, X.; He, W.-M. External electrolyte-free electrochemical one-pot cascade synthesis of 4-thiocyanato-1H-pyrazoles. Chin. Chem. Lett. 2023, 34, 107640. [Google Scholar] [CrossRef]
  65. Song, H.-Y.; Zhang, Z.-T.; Tan, H.-Y.; Lu, Y.-H.; Yang, T.-B.; Chen, J.-Y.; Ji, H.-T.; He, W.-M. Visible-Light-Promoted Electron Donor-Acceptor Complex Enabled Decarboxylative Alkylation of Quinoxalin-2(1H)-ones and N-Hydroxyphthalimide Esters with Na2S as a Catalytic Donor. Asian J. Org. Chem. 2023, 12, e202200658. [Google Scholar]
  66. Li, N.-B.; Gu, S.; Hu, C.-Q.; Wang, Y.-X.; Zhou, X.; Qiao, J.; Jiang, J.; Ji, H.-T.; He, W.-M. Visible-light-induced mesoporous graphitic carbon nitride-catalyzed trifluoromethylation and perfluoroalkylation of 4-aminocoumarins. New J. Chem. 2023, 47, 660–665. [Google Scholar] [CrossRef]
Molecules 28 01397 sch001 550
Scheme 1. Cyanation with various “CN” sources.
Scheme 1. Cyanation with various “CN” sources.
Molecules 28 01397 sch001
Molecules 28 01397 sch002 550
Scheme 2. Conditions: C (15 mm × 10 mm × 2 mm) as the anode, Pt (15 mm × 10 mm × 0.1 mm) as the cathode, 1 (0.2 mmol), 2 (0.5 mmol), LiBF4 (0.1 mmol), MeCN (6 mL), ambient temperature, undivided cell.
Scheme 2. Conditions: C (15 mm × 10 mm × 2 mm) as the anode, Pt (15 mm × 10 mm × 0.1 mm) as the cathode, 1 (0.2 mmol), 2 (0.5 mmol), LiBF4 (0.1 mmol), MeCN (6 mL), ambient temperature, undivided cell.
Molecules 28 01397 sch002
Molecules 28 01397 sch003 550
Scheme 3. Mechanistic studies.
Scheme 3. Mechanistic studies.
Molecules 28 01397 sch003
Molecules 28 01397 g001 550
Figure 1. Cyclic voltammetry experiments.
Figure 1. Cyclic voltammetry experiments.
Molecules 28 01397 g001
Molecules 28 01397 sch004 550
Scheme 4. Possible reaction mechanism.
Scheme 4. Possible reaction mechanism.
Molecules 28 01397 sch004
Table
Table 1. Optimization of the reaction conditions a.
Table 1. Optimization of the reaction conditions a.
Molecules 28 01397 i001
EntryVariation from the Standard ConditionsYield (%) b
1none83%
2Pt (+)|Pt (−) instead of C (+)|Pt (−)51%
3C(+)|C(−) instead of C(+)|Pt (−)60%
4C(+)|Cu(−) instead of C(+)|Pt (−)26%
5C(+)|Al(−) instead of C(+)|Pt (−)17%
6C(+)|Ni (−) instead of C(+)|Pt (−)trace
7C(+)|Mg (−) instead of C(+)|Pt (−)trace
8LiPF6, LiClO4, LiOAc instead of LiBF4trace
9NaBF4, H4NBF4, nBu4NBF4 instead of LiBF4trace
10DMF instead of MeCN27%
11EtOH, DCE, DMSO, THF instead of MeCNN.R.
1210 mA instead of 15 mAN.R.
1320 mA instead of 15 mA65%
14No LiBF4N.R.
a Reaction conditions: C (15 mm × 10 mm × 2 mm) as the anode, Pt (15 mm × 10 mm × 0.1 mm) as the cathode, 1a (0.1 mmol), 2a (0.25 mol), LiBF4 (50 mol%), MeCN (3 mL), ambient temperature, 9 h. b Estimated by GC-MS using diethyl phthalate as an internal reference.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

He, W.-B.; Tang, L.-L.; Jiang, J.; Li, X.; Xu, X.; Yang, T.-B.; He, W.-M. Paired Electrolysis Enabled Cyanation of Diaryl Diselenides with KSCN Leading to Aryl Selenocyanates. Molecules 2023, 28, 1397. https://doi.org/10.3390/molecules28031397

AMA Style

He W-B, Tang L-L, Jiang J, Li X, Xu X, Yang T-B, He W-M. Paired Electrolysis Enabled Cyanation of Diaryl Diselenides with KSCN Leading to Aryl Selenocyanates. Molecules. 2023; 28(3):1397. https://doi.org/10.3390/molecules28031397

Chicago/Turabian Style

He, Wei-Bao, Luo-Lin Tang, Jun Jiang, Xiao Li, Xinhua Xu, Tian-Bao Yang, and Wei-Min He. 2023. "Paired Electrolysis Enabled Cyanation of Diaryl Diselenides with KSCN Leading to Aryl Selenocyanates" Molecules 28, no. 3: 1397. https://doi.org/10.3390/molecules28031397

Article Metrics

Back to TopTop