Natural Deep Eutectic Solvent-Catalyzed Selenocyanation of

Research Article pubs.acs.org/journal/ascecg

Cite This: ACS Sustainable Chem. Eng. XXXX, XXX, XXX−XXX

Natural Deep Eutectic Solvent-Catalyzed Selenocyanation of Activated Alkynes via an Intermolecular H‑Bonding Activation Process Chao Wu,†,‡ Hai-Jing Xiao,† Shu-Wen Wang,† Man-Sheng Tang,† Zi-Long Tang,‡ Wen Xia,‡ Wen-Feng Li,§ Zhong Cao,§ and Wei-Min He*,† †

Department of Chemistry, Hunan University of Science and Engineering, Yongzhou 425100, China Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, Hunan University of Science and Technology, Xiangtan 411201, China § Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, Changsha University of Science and Technology, Changsha 410114, China

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‡

S Supporting Information *

ABSTRACT: By employing cheap and biodegradable natural deep eutectic solvent as the catalyst and reaction media, the selective selenocyanation of activated alkynes via an intermolecular H-bonding activation pathway has been achieved, which allows for the efficient construction of various Z-vinyl selenolates. KEYWORDS: Deep eutectic solvent, Multicomponent reaction, Selenocyanation, Alkynes, H-bonding

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reaction with natural DESs as both reaction media15−23 and catalyst/promoter24−29 has become an increasingly important subject in green organic synthesis.30,31 Selenium-containing molecules play important roles in organic synthesis, pharmaceutical chemistry and advanced functional materials.32 Among them, the organo-selenocyanate compounds have attracted great attention as they are not only prevalent in various pharmaceutical drug candidates and biologically active compounds but also act as versatile synthetic precursors for production of value-added chemical compounds.33 However, compared with the organic selenide synthesis,34−46 there are limited protocols for the synthesis of organo-selenocyanate compounds,47−49 especially for the construction of vinyl selenocyanates, which are very rare. In 2004, Guillemin and Veszprémi treated vinylmagnesium bromide with selenium powder in THF under nitrogen protection to produce vinyl selenolate, which then reacted with highly toxic and moisture-sensitive cyanogen bromide to form selenocyanatoethene. However, only one single example was presented (Scheme 1a).50 Recently, Ranu and co-workers reported the synthesis of E-styrenyl selenocyanates through I2catalyzed selenocyanation of styrenyl bromides with KSeCN in anhydrous DMSO (Scheme 1b).51 However, to the best of our knowledge, there is no report in the literature on the one-step construction of thermodynamically less favorable Z-vinyl

INTRODUCTION Nowadays, the industrial-scale production of organic solvents consumes a great deal of nonrenewable fossil resources and leads to environmental deterioration. Moreover, almost 20 million tons of volatile organic compounds (VOCs) are released into the natural environment per year of which a large part is due to the employment of VOCs as a reaction medium. In order to solve these problems, a tremendous amount of effort and energy have been dedicated in recent decades to develop the renewable green solvents. Accordingly, numerous chemical reactions have been studied by organic chemists under water,1 supercritical carbon dioxide,2 ionic liquids,3−5 deep eutectic solvents (DESs),6,7 among other alternative reaction medium.8−12 Among the green solvents, the ionic liquids and DESs have received particular attention because they not only can serve as an eco-friendly reaction media, capable of pushing aside VOCs, but also act as a catalyst and/ or promoter, offering striking features in line with the criteria of green chemistry. However, from eco-friendly and economic views, the nonrenewable synthetic raw material, the nonbiodegradability, toxicity, and prohibitively manufacturing cost of ionic liquid products greatly restricts their application. The natural DESs entirely represent green chemistry principles, which are made from entirely of renewable plant metabolites, for instance, ammonium salts, sugars, and natural organic acids.13 In addition to sharing similar advantages with ionic liquids (nonvolatility, thermal stability, excellent solubility, recyclability, and adjustable chemical property), DESs present specific virtues; they are biodegradable, noncytotoxic, easy preparation, and costless.14 Thus, the development of organic © XXXX American Chemical Society

Received: September 23, 2018 Revised: November 25, 2018

A

DOI: 10.1021/acssuschemeng.8b04877 ACS Sustainable Chem. Eng. XXXX, XXX, XXX−XXX

Research Article

ACS Sustainable Chemistry & Engineering

an economical and eco-friendly protocol for the synthesis of various Z-vinyl selenolates through natural DES (ChCl/ glycolic acid) catalyzed selenocyanation of activated alkynes (Scheme 1c).

Scheme 1. Synthesis of Z-Vinyl Selenocyanates

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RESULTS AND DISCUSSION We initiated the study by reacting ethyl propiolate 1a with KSeCN (1.2 equiv) in HCl (1 M, 1 mL) at ambient temperature for 12 h, and the desired (Z)-ethyl 3selenocyanatoacrylate 2a was formed in 30% yield (Z/E = 9:1, Table 1, entry 1). Encouraged by this promising result, a series of acidic aqueous solutions were examined (entries 2−8) and results revealed that the deep eutectic ChCl/glycolic acid (1:2 mol mol−1) aqueous solution was the better reaction media for this present reaction (entry 8). It is noteworthy that the glycolic acid aqueous solution displayed much lower catalytic efficiency and reaction selectivity than ChCl/glycolic acid aqueous solution (entry 4 vs 8). In the control reaction with ChCl, no selenocyanation product was observed, suggesting that the formation of the DES is necessary for the

selenolates from readily accessible alkynes under eco-friendly reaction conditions. As part of our ongoing research interest in the green synthesis,52−63 we have reported the eco-friendly functionalization of alkynes.64−69 In this paper, we report for the first time Table 1. Optimization of Reaction Conditionsa

entry

solvent

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23c 24 25 26 27d 28 29 30 31

HCl (1 M, 1 mL) HOAc (1 M, 1 mL) TFA (1 M, 1 mL) glycolic acid (1 M, 1 mL) oxalic acid (1 M, 1 mL) citric acid (1 M, 1 mL) BAIL (1 M, 1 mL) ChCl/glycolic acid (1:2) (1 M, 1 mL) ChCl (1 M, 1 mL) ChCl/glycolic acid(1:2) (1 mL) ChCl/oxalic acid (1:2) (1 mL) ChCl/citric acid (1:2) (1 mL) ChCl/tartaric acid (1:2) (1 mL) ChCl/malic acid (1:2) (1 mL) betaine/glycolic acid (1:2) (1 mL) L-carnitine/glycolic acid(1:2) (1 mL) ChCl/urea (1:2) (1 mL) ChCl/glycerol (1:2) (1 mL) ChCl/glycolic acid (1:1) (1 mL) ChCl/glycolic acid (1:3) (1 mL) ChCl/glycolic acid (1:2) (1 mL) ChCl/glycolic acid (1:2) (1 mL) ChCl/glycolic acid(1:2) (1 mL) ChCl/glycolic acid (1:2) (1 mL) ChCl/glycolic acid (1:2) (5 equiv) ChCl/glycolic acid (1:2) (4 equiv) ChCl/glycolic acid (1:2) (5 equiv) ChCl/glycolic acid (1:2) (5 equiv) ChCl/glycolic acid (1:2) (5 equiv) ChCl/glycolic acid (1:2) (5 equiv) ChCl/glycolic acid (1:2) (5 equiv)

KSeCN (X equiv) KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN KSeCN

conditions

(1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.5) (1.0) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2) (1.2)

stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, r.t., 12 h stirring, 60 °C, 12 h stirring, r.t., 12 h stirring, r.t., 12 h USI (35W/40 kHz/28−35 USI (50W/40 kHz/28−35 USI (25W/40 kHz/28−35 USI (35W/60 kHz/28−35 USI (35W/28 kHz/28−35

°C), °C), °C), °C), °C),

35 35 35 35 35

min min min min min

convb

yieldb

Z/Eb

49 46 24 55 21 26 37 63 0 76 41 39 28 35 43 37 trace trace 61 65 79 64 76 76 77 71 100 100 91 100 88

30 31 17 36 13 14 21 47 0 68 25 22 16 19 31 28 trace trace 48 53 68 53 68 69 68 57 93 93 80 92 76

9:1 12:1 8:1 10:1 9:1 9:1 7:1 18:1 − 36:1 21:1 18:1 20:1 21:1 15:1 14:1 − − 25:1 28:1 28:1 27:1 29:1 29:1 29:1 28:1 36:1 33:1 32:1 33:1 31:1

a Unless otherwise specified, the reactions were carried out in a vial in the presence of 1a (0.1 mmol), KSeCN (0.12 mmol), and solvent. When the reaction was conducted in pure DES, 1 equiv of H2O was added. 1M, 1 mol/1 mL; BAIL, 1-(3-sulfopropyl)pyridinium hydrogen sulfate. b Estimated by 1H NMR using diethyl phthalate as internal reference. c3 equiv of water was used. dThe temperature of DES was detected by thermometer.

B


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ACS Sustainable Chemistry & Engineering Table 2. Reaction Scopea

excellent performance of ChCl/glycolic acid (entry 9). In sharp contrast to the acidic aqueous solutions, the employment of pure deep eutectic ChCl/glycolic acid not only increased the reaction efficiency and the stereoselectivity but also reduced the formation of side-products (entry 10 VS 1−8). As per our expectation, the efficiency of this selenocyanation reaction was strongly dependent on the nature of the biomass DES. The employment of other deep eutectic ChCl/biomassacid mixtures (entries 11−14) or biomass-base/glycolic acid mixtures (entries 15−16) brought low-to-moderate yields, whereas the relatively weak H-bond interaction deep eutectic solvents resulted in trace conversion of 1a (entries 17 and 18). Further investigation the compositions of deep eutectic ChCl/ glycolic acid mixtures revealed that a mixture of ChCl/glycolic acid in 1:2 ratio was found to be the best choice for this reaction (entries 10 vs 19−20). Further efforts in the loadings of KSeCN and water as well as reaction temperature did not provide improved yield of the desired product (entries 21− 24). Lowering the amount of DES to 5 equiv was feasible; however, further reduction to 4 equiv led to a lower efficiency (entries 25 and 26). Exhilaratingly, treatment of 1a with KSCN in ChCl/glycolic acid (1:2) under ultrasonic radiation (35W/ 40 kHz) for 35 min resulted in formation of 2a in a 93% yield with a Z/E ratio of 36:1 (entry 27). The probable explanation for the positive association of irradiation is that the ultrasonic irradiation could increase the number of active cavitation bubbles and the size of the individual bubbles, both of which are expected to result in rapid micromixing of the reaction partners and accelerated respective reaction. Further optimization of the parameters (ultrasonic frequency and power) of ultrasonic radiation (entries 29−31) showed that 35W/40 kHz was suitable for the transformation. With the optimized reaction conditions in hand (Table 1, entry 27), we next investigated the substrate scope of this multicomponent reaction. As summarized in Table 2, propargylic carboxylates with diverse carbon chain lengths and isomeric structures reacted smoothly resulting into the desired Z-selenocyanato acrylates (2a−2k) in excellent yields. Pleasingly, the present protocol exhibited an outstanding chemoselectivity profile, as various propargylic carboxylate substrates containing alkyl (2a−2c), phenyl (2d), benzyl (2e), cyclohexyl (2f), phenemyl (2g), free OH (2h), ether (2i), cyano (2j), and bromo (2k). A host of substrates containing various natural and biologically active alcohols, such as naphthol (2l), furylalcohol (2m), 2-thiophenemethanol (2n), sesamol (2o), cinnamyl alcohol (2p), perillyl alcohol (2q), and vitamin E (2r) worked well in the selenocyanation reaction, generating the expected products in good yields. Moreover, the relatively low reaction activity of internal propargylic carboxylates can also be employed as the reaction substrates, furnishing the expected products (2s−2w) with good yields. Neither electronic effect nor steric factor of β-substituted ethyl propiolate had significant influence on this nucleophilic addition reaction. Notably, a series of electron-deficient alkynes, such as ynones, propynethioate, and proparagyl sulfonate, proved to be effective substrates, yielding the desired vinyl selenolates (2x−2ab) in good yields. To verify the practicability of this present multicomponent reaction, a scale-up reaction and a one-pot transformation were carried out. Ethyl propiolate (1a, 10 mmol) reacted with KSeCN and water under standard conditions, and the expected selenocyanation product 2a was obtained in 88% yield (Scheme 2a). Furthermore, a sequential one-pot selenocyana-

a Conditions: 1 (0.3 mmol), KSeCN (0.36 mmol), H2O (0.3 mmol), ChCl/glycolic acid (1:2) (1.5 mmol), USI (35W/40 kHz), 35 min. Isolate yields were reported. The Z/E ratios were estimated by 1H NMR. bEthyl 3-(trimethylsilyl)propiolate was used as the substrate.

tion/alkylation/reduction could be conducted to convert the SeCN group into SeMe group (Scheme 2b). Scheme 2. Large Scale Synthesis and One-Pot Transformation

Finally, investigations were also performed to check the recyclability and sustainability of the natural DES, and the transformation of ethyl propiolate 1a was chosen as the model reaction. Upon completion of the selenocyanation reaction, the product 2a undergoes in-flask extraction with minimum amounts of ethyl acetate. Then, upon simply adding fresh reagents (1a, water and KSeCN), the natural DES could be successfully reused for next reaction cycle. As shown in Figure 1, the experimental results showed that the natural DES could be reused without obvious loss in activity in five consecutive runs. A series of control experiments were performed to gain some insights into the possible mechanism. When phenylacetylene was used instead of electron-deficient alkyne as the substrate, no expected product was detected, which indicated that the electron-deficient group played a key role in this transC


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Scheme 4. First, two hydrogen bonds73−75 formed between the oxygen atom of the carboxyl group in alkyne 1 and the H atom of the hydroxyl groups (glycolic acid) in DES, resulting in enhanced polarization of carbonyl group of 1 (A), which was in resonance with a zwitterionic intermediate B. Then, the selenocyanate anion attacked the intermediate B to generate an intermediate C, in which a hydrogen bond formed between the nitrogen-atom of “SeCN” and the H atom of the hydroxyl group (ChCl) in DES. Finally, the intermediate C captured a proton (in situ generated by ultrasound-assisted self-ionization of H2O) on the reverse side of the sterically hindered H-bondactivated atom to produce the desired Z-vinyl selenocyanates 276 with concomitant release of the DES to fulfill the catalytic cycle. Water is the source of hydrogen atom in the product 2.

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CONCLUSIONS In summary, by employing cheap and biodegradable natural deep eutectic solvent as the catalyst and reaction media, the selective selenocyanation of activated alkynes via an intermolecular H-bonding activation pathway has been achieved, which allows for the efficient synthesis of various Z-vinylselenolates. The levels of selectivity achieved in DES are excellent and much higher than those obtained under other reaction conditions. The dual roles of natural DES simplified this multicomponent reaction, thus a large-scale synthesis and a one-pot sequential transformations starting from readily available raw materials were easily achieved. The present protocol (a) does not use any toxic and expensive reagents, (b) proceeds under a very mild reaction with good reaction efficiency as well as with remarkable functional-group tolerance, and (c) allows a simple and effective recycling and reusing of DES. Efforts toward clarifying the “active” role played by DES components in promoting selective Michael addition reactions will surely help to expand to develop even more novel DES-catalyzed reaction via intermolecular hydrogen-bonding activation pathways.

Figure 1. Reusable of natural DES. Conditions: 1a (1 mmol), KSeCN (1.2 mmol), H2O (1 mmol), DES (5 mmol), USI (35W/40 kHz/28− 35 °C), 35 min. 1H NMR yields were reported.

formation (Scheme 3a). Replacement of ethyl propiolate with ethyl acrylate did not deliver the selenocyanation product, Scheme 3. Control Experiments

suggesting that the alkynyl group is necessary to drive the developed selenocyanation reaction (Scheme 3b). When two common radical trapping reagents (TEMPO and BTH) were added to the reaction mixture, the transformation proceeded as normal, indicating that radical process might not be involved (Scheme 3c). On the basis of the screening conditions (Table 1, entries 4, 8−9, and 19−20) and control experimental results as well as the relevant literature,70−72 a possible mechanism indicating the crucial role of the deep eutectic ChCl/glycolic acid (1:2) in the stereoselective selenocyanation reaction is depicted in

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EXPERIMENTAL SECTION

General Procedure for the Synthesis of Compound 2. In a vial was placed alkyne (0.3 mmol), ChCl/glycolic acid (1:2) (0.45 g, 1.5 mmol), KSeCN (0.36 mmol), water (0.3 mmol), and then the contents were reacted under ultrasound irradiation. Upon completion, the reaction mixture was purified by column chromatography on silica gel (eluent: hexanes/ethyl acetate) to afford 2.

Scheme 4. Plausible Mechanism

D


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(14) Kudłak, B.; Owczarek, K.; Namieśnik, J. Selected issues related to the toxicity of ionic liquids and deep eutectic solventsa review. Environ. Sci. Pollut. Res. 2015, 22, 11975−11992. (15) Zhang, M.; Liu, P.; Liu, Y.-H.; Shang, Z.-R.; Hu, H.-C.; Zhang, Z.-H. Magnetically separable graphene oxide anchored sulfonic acid: a novel, highly efficient and recyclable catalyst for one-pot synthesis of 3,6-di(pyridin-3-yl)-1H-pyrazolo[3,4-b]pyridine-5-carbonitriles in deep eutectic solvent under microwave irradiation. RSC Adv. 2016, 6, 106160−106170. (16) Ali, M. C.; Yang, Q.; Fine, A. A.; Jin, W.; Zhang, Z.; Xing, H.; Ren, Q. Efficient removal of both basic and non-basic nitrogen compounds from fuels by deep eutectic solvents. Green Chem. 2016, 18, 157−164. (17) Park, T.-J.; Lee, S. H. Deep eutectic solvent systems for FeCl3catalyzed oxidative polymerization of 3-octylthiophene. Green Chem. 2017, 19, 910−913. (18) Zhang, M.; Liu, Y.-H.; Shang, Z.-R.; Hu, H.-C.; Zhang, Z.-H. Supported molybdenum on graphene oxide/Fe3O4: An efficient, magnetically separable catalyst for one-pot construction of spirooxindole dihydropyridines in deep eutectic solvent under microwave irradiation. Catal. Commun. 2017, 88, 39−44. (19) Zhang, M.; Fu, Q.-Y.; Gao, G.; He, H.-Y.; Zhang, Y.; Wu, Y.-S.; Zhang, Z.-H. Catalyst-Free, Visible-Light Promoted One-Pot Synthesis of Spirooxindole-Pyran Derivatives in Aqueous Ethyl Lactate. ACS Sustainable Chem. Eng. 2017, 5, 6175−6182. (20) Liang, Q.; Xiao, Y.; Liu, K.; Zhong, C.; Zeng, M.; Xiao, F. X. Cr(VI)-Induced Autophagy Protects L-02 Hepatocytes from Apoptosis Through the ROS-AKT-mTOR Pathway. Cell. Physiol. Biochem. 2018, 51, 1863−1878. (21) Cicco, L.; Ríos-Lombardía, N.; Rodríguez-Á lvarez, M. J.; Morís, F.; Perna, F. M.; Capriati, V.; García-Á lvarez, J.; González-Sabín, J. Programming cascade reactions interfacing biocatalysis with transition-metal catalysis in Deep Eutectic Solvents as biorenewable reaction media. Green Chem. 2018, 20, 3468−3475. (22) Muhammad, M. H.; Chen, X.-L.; Yu, B.; Qu, L.-B.; Zhao, Y.-F. Applications of H-phosphonates for C element bond formation. Pure Appl. Chem. 2018, 91, 33−41. (23) Messa, F.; Perrone, S.; Capua, M.; Tolomeo, F.; Troisi, L.; Capriati, V.; Salomone, A. Towards a sustainable synthesis of amides: chemoselective palladium-catalysed aminocarbonylation of aryl iodides in deep eutectic solvents. Chem. Commun. 2018, 54, 8100− 8103. (24) Hu, S.; Zhang, Z.; Zhou, Y.; Song, J.; Fan, H.; Han, B. Direct conversion of inulin to 5-hydroxymethylfurfural in biorenewable ionic liquids. Green Chem. 2009, 11, 873−877. (25) Zhang, Z.-H.; Zhang, X.-N.; Mo, L.-P.; Li, Y.-X.; Ma, F.-P. Catalyst-free synthesis of quinazoline derivatives using low melting sugar-urea-salt mixture as a solvent. Green Chem. 2012, 14, 1502− 1506. (26) Yan, S.; Zhang, C.; Wang, Y.-H.; Cao, Z.; Zheng, Z.; Hu, X.-P. Synthesis of new chiral ferrocenyl P,N-ligands with a benzoxazole ring and their application in Ag-catalyzed asymmetric [3 + 2] cycloaddition. Tetrahedron Lett. 2013, 54, 3669−3672. (27) Yadav, U. N.; Shankarling, G. S. Room temperature ionic liquid choline chloride−oxalic acid: A versatile catalyst for acid-catalyzed transformation in organic reactions. J. Mol. Liq. 2014, 191, 137−141. (28) Wang, Q.; Yao, X.; Geng, Y.; Zhou, Q.; Lu, X.; Zhang, S. Deep eutectic solvents as highly active catalysts for the fast and mild glycolysis of poly(ethylene terephthalate)(PET). Green Chem. 2015, 17, 2473−2479. (29) Hu, Y.; Li, N.; Li, G.; Wang, A.; Cong, Y.; Wang, X.; Zhang, T. Sustainable production of pyromellitic acid with pinacol and diethyl maleate. Green Chem. 2017, 19, 1663−1667. (30) Liu, P.; Hao, J.-W.; Mo, L.-P.; Zhang, Z.-H. Recent advances in the application of deep eutectic solvents as sustainable media as well as catalysts in organic reactions. RSC Adv. 2015, 5, 48675−48704. (31) Alonso, D. A.; Baeza, A.; Chinchilla, R.; Guillena, G.; Pastor, I. M.; Ramón, D. J. Deep Eutectic Solvents: The Organic Reaction Medium of the Century. Eur. J. Org. Chem. 2016, 2016, 612−632.

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acssuschemeng.8b04877. 1

H and 13C NMR spectra of compounds 3 (PDF)

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Wei-Min He: 0000-0002-9481-6697 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS We are grateful for financial support from the postfunded projects of Hunan University of Science and Engineering and the National Natural Science Foundation of China (no. 21877034).

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REFERENCES

(1) Simon, M.-O.; Li, C.-J. Green chemistry oriented organic synthesis in water. Chem. Soc. Rev. 2012, 41, 1415−1427. (2) Olmos, A.; Asensio, G.; Pérez, P. J. Homogeneous Metal-Based Catalysis in Supercritical Carbon Dioxide as Reaction Medium. ACS Catal. 2016, 6, 4265−4280. (3) Dai, C.; Zhang, J.; Huang, C.; Lei, Z. Ionic Liquids in Selective Oxidation: Catalysts and Solvents. Chem. Rev. 2017, 117, 6929−6983. (4) Xie, L.-Y.; Peng, S.; Lu, L.-H.; Hu, J.; Bao, W.-H.; Zeng, F.; Tang, Z.; Xu, X.; He, W.-M. Brønsted Acidic Ionic Liquid-Promoted Amidation of Quinoline N-Oxides with Nitriles. ACS Sustainable Chem. Eng. 2018, 6, 7989−7994. (5) Wu, C.; Lu, L.-H.; Peng, A.-Z.; Jia, G.-K.; Peng, C.; Cao, Z.; Tang, Z.; He, W.-M.; Xu, X. Ultrasound-promoted Brønsted acid ionic liquid-catalyzed hydrothiocyanation of activated alkynes under minimal solvent conditions. Green Chem. 2018, 20, 3683−3688. (6) Smith, E. L.; Abbott, A. P.; Ryder, K. S. Deep Eutectic Solvents (DESs) and Their Applications. Chem. Rev. 2014, 114, 11060−11082. (7) Jordan, A.; Gathergood, N. Biodegradation of ionic liquids - a critical review. Chem. Soc. Rev. 2015, 44, 8200−8237. (8) Gu, Y.; Jerome, F. Bio-based solvents: an emerging generation of fluids for the design of eco-efficient processes in catalysis and organic chemistry. Chem. Soc. Rev. 2013, 42, 9550−9570. (9) Wei, W.; Cui, H.; Yue, H.; Yang, D. Visible-light-enabled oxyazidation of alkenes leading to α-azidoketones in air. Green Chem. 2018, 20, 3197−3202. (10) Wei, W.; Wang, L.; Bao, P.; Shao, Y.; Yue, H.; Yang, D.; Yang, X.; Zhao, X.; Wang, H. Metal-Free C(sp2)−H/N−H CrossDehydrogenative Coupling of Quinoxalinones with Aliphatic Amines under Visible-Light Photoredox Catalysis. Org. Lett. 2018, 20, 7125− 7130. (11) Clarke, C. J.; Tu, W.-C.; Levers, O.; Bröhl, A.; Hallett, J. P. Green and Sustainable Solvents in Chemical Processes. Chem. Rev. 2018, 118, 747−800. (12) Li, R.; Chen, X.; Wei, S.; Sun, K.; Fan, L.; Liu, Y.; Qu, L.; Zhao, Y.; Yu, B. A Visible-Light-Promoted Metal-Free Strategy towards Arylphosphonates: Organic-Dye-Catalyzed Phosphorylation of Arylhydrazines with Trialkylphosphites. Adv. Synth. Catal. 2018, 360, 4807−4813. (13) Paiva, A.; Craveiro, R.; Aroso, I.; Martins, M.; Reis, R. L.; Duarte, A. R. C. Natural Deep Eutectic Solvents − Solvents for the 21st Century. ACS Sustainable Chem. Eng. 2014, 2, 1063−1071. E


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ACS Sustainable Chemistry & Engineering (32) Nogueira, C. W.; Zeni, G.; Rocha, J. B. T. Organoselenium and Organotellurium Compounds: Toxicology and Pharmacology. Chem. Rev. 2004, 104, 6255−6286. (33) 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. (34) Sun, K.; Wang, X.; Lv, Y.; Li, G.; Jiao, H.; Dai, C.; Li, Y.; Zhang, C.; Liu, L. Peroxodisulfate-mediated selenoamination of alkenes yielding amidoselenide-containing sulfamides and azoles. Chem. Commun. 2016, 52, 8471−8474. (35) Zhong, S.; Liu, Y.; Cao, X.; Wan, J.-P. KIO3-Catalyzed Domino C(sp2)−H Bond Sulfenylation and C−N Bond Oxygenation of Enaminones toward the Synthesis of 3-Sulfenylated Chromones. ChemCatChem 2017, 9, 465−468. (36) Gao, C.; Wu, G.; Min, L.; Liu, M.; Gao, W.; Ding, J.; Chen, J.; Huang, X.; Wu, H. Copper-Catalyzed Three-Component Coupling Reaction of Azoles, Se Powder, and Aryl Iodides. J. Org. Chem. 2017, 82, 250−255. (37) Sun, P.; Jiang, M.; Wei, W.; Min, Y.; Zhang, W.; Li, W.; Yang, D.; Wang, H. Copper-Catalyzed Selenylation of Imidazo[1,2a]pyridines with Selenium Powder via a Radical Pathway. J. Org. Chem. 2017, 82, 2906−2913. (38) Sun, K.; Wang, X.; Fu, F.; Zhang, C.; Chen, Y.; Liu, L. Metalfree selenosulfonylation of alkynes: rapid access to β-(seleno)vinyl sulfones via a cationic-species-induced pathway. Green Chem. 2017, 19, 1490−1493. (39) Fang, Y.; Zhu, Z.-L.; Xu, P.; Wang, S.-Y.; Ji, S.-J. Aerobic radical-cascade cycloaddition of isocyanides, selenium and imidamides: facile access to 1,2,4-selenadiazoles under metal-free conditions. Green Chem. 2017, 19, 1613−1618. (40) Liang, Q.; Zhang, Y.; Zeng, M.; Guan, L.; Xiao, Y.; Xiao, F. The role of IP3R-SOCCs in Cr(vi)-induced cytosolic Ca2+ overload and apoptosis in L-02 hepatocytes. Toxicol. Res. 2018, 7, 521−528. (41) Guo, T.; Wei, X.-N.; Wang, H.-Y.; Zhu, Y.-L.; Zhao, Y.-H.; Ma, Y.-C. Copper-catalyzed chalcogenation of imidazoheterocycles with sulfur/selenium powder and coumarinyl triflates. Org. Biomol. Chem. 2017, 15, 9455−9464. (42) Wei, W.; Wang, L.; Yue, H.; Bao, P.; Liu, W.; Hu, C.; Yang, D.; Wang, H. Metal-Free Visible-Light-Induced C−H/C−H CrossDehydrogenative-Coupling of Quinoxalin-2(H)-ones with Simple Ethers. ACS Sustainable Chem. Eng. 2018, 6, 17252. (43) Fu, X.; Meng, Y.; Li, X.; Stępień, M.; Chmielewski, P. J. Extension of antiaromatic norcorrole by cycloaddition. Chem. Commun. 2018, 54, 2510−2513. (44) Yang, D.; Li, G.; Xing, C.; Cui, W.; Li, K.; Wei, W. Metal- and photocatalyst-free visible-light-promoted regioselective selenylation of coumarin derivatives via oxidation-induced C−H functionalization. Org. Chem. Front. 2018, 5, 2974−2979. (45) Xiao, Y.; Zeng, M.; Yin, L.; Li, N.; Xiao, F. Clusterin increases mitochondrial respiratory chain complex I activity and protects against hexavalent chromium-induced cytotoxicity in L-02 hepatocytes. Toxicol. Res. 2019, 8, 15−24. (46) Wu, G.; Min, L.; Li, H.; Gao, W.; Ding, J.; Huang, X.; Liu, M.; Wu, H. Metal-free synthesis of alkynyl alkyl selenides via threecomponent coupling of terminal alkynes, Se, and epoxides. Green Chem. 2018, 20, 1560−1563. (47) Muniraj, N.; Dhineshkumar, J.; Prabhu, K. R. N-Iodosuccinimide Catalyzed Oxidative Selenocyanation and Thiocyanation of Electron Rich Arenes. ChemistrySelect 2016, 1, 1033−1038. (48) Sun, K.; Lv, Y.; Chen, Y.; Zhou, T.; Xing, Y.; Wang, X. A novel metal-free method for the selenocyanation of aromatic ketones to afford [small alpha]-carbonyl selenocyanates. Org. Biomol. Chem. 2017, 15, 4464−4467. (49) Sun, K.; Chen, X.-L.; Li, S.-J.; Wei, D.-H.; Liu, X.-C.; Zhang, Y.L.; Liu, Y.; Fan, L.-L.; Qu, L.-B.; Yu, B.; Li, K.; Sun, Y.-Q.; Zhao, Y.-F. Copper-Catalyzed Radical Cascade Cyclization To Access 3Sulfonated Indenones with the AIE Phenomenon. J. Org. Chem. 2018, 83, 14419−14430.

(50) Bajor, G.; Veszprémi, T.; Riague, E. H.; Guillemin, J.-C. Alkenyl Selenols and Selenocyanates: Synthesis, Spectroscopic Characterization by Photoelectron Spectroscopy, and Quantum Chemical Study. Chem. - Eur. J. 2004, 10, 3649−3656. (51) Maity, P.; Paroi, B.; Ranu, B. C. Transition-Metal-Free Iodine Catalyzed Selenocayanation of Styrenyl Bromides and an Easy Access to Benzoselenophenes via Intermediacy of Styrenyl Selenocyanate. Org. Lett. 2017, 19, 5748−5751. (52) Xie, L.-Y.; Duan, Y.; Lu, L.-H.; Li, Y.-J.; Peng, S.; Wu, C.; Liu, K.-J.; Wang, Z.; He, W.-M. Fast, Base-Free and Aqueous Synthesis of Quinolin-2(1H)-ones under Ambient Conditions. ACS Sustainable Chem. Eng. 2017, 5, 10407−10412. (53) Xie, L.-Y.; Li, Y.-J.; Qu, J.; Duan, Y.; Hu, J.; Liu, K.-J.; Cao, Z.; He, W.-M. A base-free, ultrasound accelerated one-pot synthesis of 2sulfonylquinolines in water. Green Chem. 2017, 19, 5642−5646. (54) Bao, W.-H.; Wu, C.; Wang, J.-T.; Xia, W.; Chen, P.; Tang, Z.; Xu, X.; He, W.-M. Molecular iodine-mediated synthesis of thiocarbamates from thiols, isocyanides and water under metal-free conditions. Org. Biomol. Chem. 2018, 16, 8403−8407. (55) Liu, K.-J.; Fu, Y.-L.; Xie, L.-Y.; Wu, C.; He, W.-B.; Peng, S.; Wang, Z.; Bao, W.-H.; Cao, Z.; Xu, X.; He, W.-M. Green and Efficient: Oxidation of Aldehydes to Carboxylic Acids and Acid Anhydrides with Air. ACS Sustainable Chem. Eng. 2018, 6, 4916− 4921. (56) Liu, K.-J.; Jiang, S.; Lu, L.-H.; Tang, L.-L.; Tang, S.-S.; Tang, H.-S.; Tang, Z.; He, W.-M.; Xu, X. Bis(methoxypropyl) etherpromoted oxidation of aromatic alcohols into aromatic carboxylic acids and aromatic ketones with O2 under metal- and base-free conditions. Green Chem. 2018, 20, 3038−3043. (57) Liu, K.-J.; Zeng, X.-L.; Zhang, Y.; Wang, Y.; Xiao, X.-S.; Yue, H.; Wang, M.; Tang, Z.; He, W.-M. Palladium-Catalyzed Reductive Coupling of Nitroarenes with Phenols leading to N-Cyclohexylanilines. Synthesis 2018, 50, 4637−4644. (58) Wu, C.; Wang, J.; Zhang, X.-Y.; Jia, G.-K.; Cao, Z.; Tang, Z.; Yu, X.; Xu, X.; He, W.-M. Palladium-catalyzed selective synthesis of 3,4-dihydroquinazolines from electron-rich arylamines, electron-poor arylamines and glyoxalates. Org. Biomol. Chem. 2018, 16, 5050−5054. (59) Xie, L.-Y.; Peng, S.; Jiang, L.-L.; Peng, X.; Xia, W.; Yu, X.; Wang, X.-X.; Cao, Z.; He, W.-M. AgBF4-Catalyzed Deoxygenative C2-amination of Quinoline N-Oxides with Isothiocyanates. Org. Chem. Front. 2018, DOI: 10.1039/C8QO01128A. (60) Xie, L.-Y.; Peng, S.; Liu, F.; Chen, G.-R.; Xia, W.; Yu, X.; Li, W.F.; Cao, Z.; He, W.-M. Metal-free deoxygenative sulfonylation of quinoline N-oxides with sodium sulfinates via a dual radical coupling process. Org. Chem. Front. 2018, 5, 2604−2609. (61) Xie, L.-Y.; Peng, S.; Liu, F.; Yi, J.-Y.; Wang, M.; Tang, Z.; Xu, X.; He, W.-M. Metal-free Deoxygenative 2-Amidation of Quinoline Noxides with Nitriles via a Radical Activation Pathway. Adv. Synth. Catal. 2018, 360, 4259−4264. (62) Xie, L.-Y.; Qu, J.; Peng, S.; Liu, K.-J.; Wang, Z.; Ding, M.-H.; Wang, Y.; Cao, Z.; He, W.-M. Selectfluor-mediated regioselective nucleophilic functionalization of N-heterocycles under metal- and base-free conditions. Green Chem. 2018, 20, 760−764. (63) Xie, L.-Y.; Peng, S.; Tan, J.-X.; Sun, R.-X.; Yu, X.; Dai, N.-N.; Tang, Z.-L.; Xu, X.; He, W.-M. Waste-Minimized Protocol for the Synthesis of Sulfonylated N-Heteroaromatics in Water. ACS Sustainable Chem. Eng. 2018, 6, 16976−16981. (64) Wu, C.; Xin, X.; Fu, Z.-M.; Xie, L.-Y.; Liu, K.-J.; Wang, Z.; Li, W.; Yuan, Z.-H.; He, W.-M. Water-controlled selective preparation of α-mono or α,α′-dihalo ketones via catalytic cascade reaction of unactivated alkynes with 1,3-dihalo-5,5-dimethylhydantoin. Green Chem. 2017, 19, 1983−1989. (65) Lu, L.-H.; Zhou, S.-J.; Sun, M.; Chen, J.-L.; Xia, W.; Yu, X.; Xu, X.; He, W.-M. Metal- and Solvent-free Ultrasonic Multicomponent Synthesis of (Z)-β-Iodo Vinylthiocyanates. ACS Sustainable Chem. Eng. 2019, 7, 1574−1579. (66) Wang, Z.; Yang, L.; Liu, H.-L.; Bao, W.-H.; Tan, Y.-Z.; Wang, M.; Tang, Z.; He, W.-M. Selective synthesis of quaternary carbon F


Research Article

ACS Sustainable Chemistry & Engineering propargylamines from amines, alkynes, and alkynes under neat condition. Chin. J. Org. Chem. 2018, 38, 2639−2647. (67) Wu, C.; Wang, Z.; Hu, Z.; Zeng, F.; Zhang, X.-Y.; Cao, Z.; Tang, Z.; He, W.-M.; Xu, X.-H. Direct synthesis of alkenyl iodides via indium-catalyzed iodoalkylation of alkynes with alcohols and aqueous HI. Org. Biomol. Chem. 2018, 16, 3177−3180. (68) Lu, L.-H.; Zhou, S.-J.; He, W.-B.; Xia, W.; Chen, P.; Yu, X.; Xu, X.; He, W.-M. Metal-free difunctionalization of alkynes leading to alkenyl dithiocyanates and alkenyl diselenocyanates at room temperature. Org. Biomol. Chem. 2018, 16, 9064−9068. (69) Hao, S.-h.; Li, L.-X.; Dong, D.-Q.; Wang, Z.-L.; Yu, X.-Y. Synthesis of coumarins derivatives via decarboxylative cross-coupling of coumarin-3-carboxylic acid with benzylic C(sp3)-H bond. Tetrahedron Lett. 2018, 59, 4073−4075. (70) Zhu, A.; Wang, M.; Li, L.; Wang, J. Tetramethylguanidiumbased ionic liquids as efficient and reusable catalysts for the synthesis of biscoumarin at room temperature. RSC Adv. 2015, 5, 73974− 73979. (71) Ma, C.-T.; Liu, P.; Wu, W.; Zhang, Z.-H. Low melting oxalic acid/proline mixture as dual solvent/catalyst for efficient synthesis of 13-aryl-13H-benzo[g]benzothiazolo[2,3-b]buinazoline-5,4-diones under microwave irradiation. J. Mol. Liq. 2017, 242, 606−611. (72) Yang, J.; Mei, F.; Fu, S.; Gu, Y. Facile synthesis of 1,4-diketones via three-component reactions of α-ketoaldehyde, 1,3-dicarbonyl compound, and a nucleophile in water. Green Chem. 2018, 20, 1367− 1374. (73) Dong, K.; Zhang, S.; Wang, J. Understanding the hydrogen bonds in ionic liquids and their roles in properties and reactions. Chem. Commun. 2016, 52, 6744−6764. (74) Yang, L.; Wu, Y.; Yang, Y.; Wen, C.; Wan, J.-P. Catalyst-free synthesis of 4-acyl-NH-1,2,3-triazoles by water-mediated cycloaddition reactions of enaminones and tosyl azide. Beilstein J. Org. Chem. 2018, 14, 2348−2353. (75) Xie, P.; Wang, J.; Fan, J.; Liu, Y.; Wo, X.; Loh, T.-P. The COH/P-H dehydrative cross-coupling for the construction of the P-C bond under metal-free conditions. Green Chem. 2017, 19, 2135−2139. (76) Xie, P.; Wang, J.; Liu, Y.; Fan, J.; Wo, X.; Fu, W.; Sun, Z.; Loh, T.-P. Water-promoted C-S bond formation reactions. Nat. Commun. 2018, 9, 1321−1328.

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Natural Deep Eutectic Solvent-Catalyzed Selenocyanation of

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