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Communication

N, S Co-Coordinated Zinc Single-Atom Catalysts for N-Alkylation of Aromatic Amines with Alcohols: The Role of S-Doping in the Reaction

by
Xueping Zhang
1,
Qiang Zhang
2,
Jiacheng Reng
1,
Yamei Lin
3,
Yongxing Tang
1,
Guigao Liu
1,
Pengcheng Wang
1 and
Guo-Ping Lu
1,*
1
School of Chemistry and Chemical Engineering, Nanjing University of Science & Technology, Xiaolingwei 200, Nanjing 210094, China
2
School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou 215009, China
3
School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Wenyuanstreet 200, Nanjing 210032, China
*
Author to whom correspondence should be addressed.
Nanomaterials 2023, 13(3), 445; https://doi.org/10.3390/nano13030445
Submission received: 5 January 2023 / Revised: 15 January 2023 / Accepted: 16 January 2023 / Published: 21 January 2023
(This article belongs to the Special Issue Porous Carbon Nanocomposites for Catalysis)
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Abstract

:
S-doping emerged as a promising approach to further improve the catalytic performance of carbon-based materials for organic synthesis. Herein, a facile and gram-scale strategy was developed using zeolitic imidazole frameworks (ZIFs) as a precursor for the fabrication of the ZIF-derived N, S co-doped carbon-supported zinc single-atom catalyst (CNS@Zn1-AA) via the pyrolysis of S-doped ZIF-8, which was modified by aniline, ammonia and thiourea and prepared by one-pot ball milling at room temperature. This catalyst, in which Zn is dispersed as the single atom, displays superior activity in N-alkylation via the hydrogen-borrowing strategy (120 °C, turnover frequency (TOF) up to 8.4 h−1). S-doping significantly enhanced the catalytic activity of CNS@Zn1-AA, as it increased the specific surface area and defects of this material and simultaneously increased the electron density of Zn sites in this catalyst. Furthermore, this catalyst had excellent stability and recyclability, and no obvious loss in activity after eight runs.

Graphical Abstract

1. Introduction

Amines are highly valuable compounds in the field of fine chemicals and have broad applications in agrochemicals, pharmaceuticals, dyes and catalysts [1,2,3,4,5]. The N-alkylation of amines via the hydrogen-borrowing process is green and efficient for the preparation of amines owing to its step and atom economy [6,7,8,9]. In this field, noble metal catalytic systems such as Ru [10], Rh [11], Ir [12], Re [13], Ag [14], Au [15] and Pt [16], have been applied widely; meanwhile, the hydrogen-borrowing capacity of non-noble metal-based catalysts, including Fe [17,18,19], Co [20], Ni [21,22], Cu [23], Hf [24], Cr [25], Mn [26,27] and Mo [28], has also been explored (Figure 1). Although a large number of efficient catalysts have been developed for this reaction, the exploration of novel catalysts to improve the catalytic efficiency and reduce costs is still one of the keys to the development of this field.
More recently, the construction of C-C and C-N bonds via the hydrogen-borrowing pathway catalyzed by zinc has attracted the attention of researchers. In 2020, Mannathan’s group first reported on the zinc nitrate hexahydrate-catalyzed N-alkylation of amines with alcohols [29]. However, this protocol suffered from limits, including harsh conditions and an unrecyclable catalyst. Our group developed a lignin-derived Zn single-atom/N-doped porous-carbon catalyst (LCN@Zn-SAC) for the hydrogen auto-transfer α-alkylation of aromatic ketones with alcohols, in which the Zn electron density is inversely proportional to the reaction energy barriers [30]. Therefore, the coordination between the electron-rich Zn sites and the less-electronegative C, P and S [31,32] may improve the borrowing hydrogen ability of Zn sites.
Single-atom catalysts (SACs) have been widely applied in heterogeneous catalysis because of their definite metal active sites (MASs), high atomic utilization efficiency and excellent performance [33,34,35]. Their relatively simple and clear structure is an excellent model for studying the electronic and geometric structure of MASs, which provides a feasible strategy for the investigation of their catalytic mechanism [36,37,38,39]. N-doped carbon materials are cheap and powerful supports for SACs, in which nitrogen can stabilize single-atom metals effectively [40,41,42].
Zeolite imidazole frameworks (ZIFs) have excellent pore structure and dopability, and high nitrogen content, which are ideal precursors for the synthesis of N-doped carbon-supported single-atom catalysts [43,44,45,46]. Nevertheless, the preparation of ZIFs suffers from several limits, such as a slow nucleation rate and large size of ZIFs [47,48,49]. Both amines and ball-milling can accelerate the nucleation of ZIFs and reduce ZIFs’ particle sizes [35,50,51,52]. Based on the above results, we reason that ball milling in the presence of amines may be an alternative strategy for the synthesis of ZIF to accelerate nucleation and produce smaller ZIF particles.
Inspired by these reports, we were prompted to explore the possibility of heteroatom-doped Zn-SAC in N-alkylation. Herein, we report a S-doped ZIF-8 produced by one-pot ball-milling, and the ZIF-derived N, S co-doped carbon-supported zinc single-atom catalyst (CNS@Zn1-AA) was obtained by pyrolysis. Using thiourea as a sulfur source, ammonia and aniline were used to accelerate the precipitation of ZIFs and control the size of ZIFs [51]. This synthetic approach has several advantages, including its simple and scalable procedure, small amount of solvent, inexpensive raw materials and relatively high zinc loading (3.88 wt.%). Compared with previous non-noble metal catalysts, the performance of this catalyst was among the best in the N-alkylation of aromatic amines with alcohols (120 °C, TOF up to 8.4 h−1) (Figure 1).

2. Results and Discussion

2.1. Characterization of CNS@Zn1-AA

As illustrated in Scheme 1, ZIF-8-AA@S was prepared by ball-milling, in which thiourea, aniline and ammonia were used as the additives. Then, CNS@Zn1-AA was obtained by the pyrolysis of ZIF-8-AA@S. Other Zn@NCs, whose naming rules are shown in Table 1, were prepared by the same procedure, except for the types of additives.
The roles of aniline and ammonia in the synthesis of ZIFs were investigated by control experiments and SEM and XRD tests. Spherical ZIFs were formed in the presence of aniline (Figure 2a,b), while irregular flake and rod ZIFs were generated in the absence of aniline (Figure 2c,d). Meanwhile, the XRD characterization proved that aniline was essential for the formation of stable ZIFs’ crystal structures (Figure 2e). The addition of ammonia did not change the crystal structure, but had a significant effect on the particle size of ZIFs. The particle size order of ZIFs was ZIF-8-An@S > ZIF-8@S > ZIF-8-Am@S > ZIF-8-AA@S. Therefore, it can be concluded that (1) aniline, as a coordination modulator, could adjust the morphology of ZIF and promote self-assembly to obtain ZIFs with a stable crystal structure [51]; (2) ammonia played a role in accelerating the nucleation of ZIFs and reducing the particle size of ZIF [53].
The role of S-doping in the material was investigated by BET and Raman tests. Both N2 adsorption isotherms of CN@Zn1-AA and CNS@Zn1-AA were type IV characteristic curves. The BET surface area could be improved by S-doping (964 m2/g vs. 1080 m2/g), while the average pore diameter decreased from 2.9 nm to 2.1 nm (Figure S1, Table S1). According to the Raman spectra, the order of ID/IG was CN@Zn1-AA (1.026) < CNS@Zn1-AA (1.048) (Figure S2), indicating that S-doping reduced the graphitization degree and promoted the formation of the pore structure and defects [54,55], which is consistent with the BET results. CNS@Zn1-AA presented two broad peaks at 24° and 43°, which were assigned to the (002) and (101) crystal planes of graphitic carbon materials. No Zn signal was observed, excluding the presence of large crystal particles of the Zn species (Figure S3).
The chemical state of CNS@Zn1-AA was investigated by XPS (Figure S4). The peaks at 284.3 eV, 284.8 eV, 285.1 eV and 286.9 eV belonged to C-S, C=C, C-N (or C-C) and C=O (Figure S4a) [56]. There were four peaks, 398.3 eV (pyridinic N), 399.5 eV (Zn–N), 401.3 eV (pyrrolic N) and 403.1 eV (graphitic N), in the XPS spectrum of N 1s (Figure S4b) [57]. In the S 2p spectrum (Figure S4c), the binding energy peaks located at 164.1 and 165.4 eV could be assigned to the 2p3/2 and 2p1/2 spin-orbitals of the C/Zn–S–C group, and the peaks at 167.9 eV and 169.2 eV belonged to oxidized S and N-S [58]. The XPS spectrum of Zn 2p had two relatively weak peaks centered at 1021.5 eV (Zn 2p3/2) and 1044.9 eV (Zn 2p1/2) (Figure S4d) [59]. In addition, the amount of Zn in CNS@Zn1-AA was determined by ICP-MS to be 3.88 wt.% (Table S2).
No highly crystalline Zn species were observed via TEM (Figure 3a), which was consistent with the results of XRD. Furthermore, high-angle annular dark-field STEM (HAADF-STEM) was performed to investigate the Zn configurations in CNS@Zn1-AA at the atomic level (Figure 3b). Large amounts of bright dots marked with red circles represent isolated Zn atoms. The EDX element mapping images showed uniformly distributed N, O, S and Zn signals, indicating that Zn, N and S were successfully doped into the carbon matrix (Figure 3c–f).
The electronic and coordination structure of the Zn sites in CNS@Zn1-AA were further unraveled at the atomic level by X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) fitting [60,61,62]. As shown in Figure 4a, the Zn K-edge X-ray absorption near-edge structure (XANES) of CNS@Zn1-AA was compared with those of Zn foil, ZnO and zinc phthalocyanine (ZnPc). The edge positions of CNS@Zn1-AA were located between those of Zn foil and ZnO, demonstrating that the average oxidation state of Zn was between 0 and +2 [63,64,65]. EXAFS fitting was carried out to analyze the chemical configuration of Zn atoms in CNS@Zn1-AA. The peak at 1.63 Å was observed by the contribution curves of Zn-N (1.56 Å) and Zn-S (1.83 Å) (Figure 4b), and no obvious peak was located at the position of Zn-Zn coordination (2.30 Å) (Figure 4c), in agreement with the above XRD and HAADF-STEM results, which further confirmed the existence of Zn as a single atom in CNS@Zn1-AA. After fitting with the IFEFFIT package, the local atomic bond coordination number ratio between the Zn-N and Zn-S scattering paths was close to 3.7:1 (Table S3). Based on the above results, the chemical coordination configuration of CNS@Zn1-AA could be understood as the Zn single-atom centers coordinated with 3~4 N and 1 S.

2.2. Catalytic Performance

The catalytic performance of CNS@Zn1-AA was investigated by choosing the alkylation of aniline with benzyl alcohol as a model reaction (Table 2). Neither the catalyst nor the base alone could achieve good results (entries 1 and 2). The activity of commercial zinc catalysts is poor (entries 4–6). The catalytic activity of CNS@Zn1-AA was significantly higher than that of CN@Zn1-AA due to S doping (entries 3 and 7). Aniline and ammonia were also necessary to maintain the catalytic activity of CNS@Zn1-AA (entries 3, 8 and 9), which can be attributed to the more stable crystal structure and smaller size of ZIFs, thereby resulting in this material having a larger specific surface area. After screening different reaction times and bases, the combination of 12 h and KOH was the best option (entries 10–13).
To further confirm the general applicability of this catalyst, the substrate scope of N-alkylation was investigated (Scheme 2). Both anilines containing electron-withdrawing groups (-Br) and electron-donating groups (-Me, -Ph) (3a–3e) could be applied in the protocol. In the cases of 2-aminopyridine and 2-aminobenzothiazole, the target products (3f, 3g) were obtained in a high yield. Adenine failed to react with benzyl alcohol (3h), and long-chain fatty amines exhibited poor reactivity in this system (3i, 3j). Both 2-thiophenemethanol and 2-pyridinemethanol resulted in the production of the corresponding products in high yields (3k, 3l). Inert aliphatic alcohol could also react with aniline to yield the final products (3q–3u), but a higher temperature was required in most cases. Only imine could be formed in the reaction of cinnamyl alcohol with aniline (3o). 4-Chloro-N-(2-furylmethyl) aniline (3v) and 4-bromine-N-(2-furylmethyl) aniline (3w) were also obtained with high yields by this protocol, both of which were crucial intermediates for the synthesis of pharmaceuticals [66,67,68].

2.3. Kinetic Experiments and DFT Calculations

In order to confirm the type of mechanism of the hydrogen-borrowing process (Meerwein–Ponndorf–Verley (MPV)-type or metal hydride-type), the reaction of o-hydroxychalcone with benzyl alcohol over CNS@Zn1-AA was performed (Scheme S1). The C=C bond of o-hydroxychalcone was reduced selectively, while the carbonyl group would be selectively reduced in the MPV reaction [69]; so, this reaction was more inclined to be a metal hydride-type reaction.
In the H/D kinetic isotope effect (KIE) experiment (Scheme 3), the kH/kD value was measured by parallel experiments using benzyl alcohol (PhCH2OH) or isotope-labeled benzyl alcohol (PhCD2OH) as substrates, obtaining a value kH/kD of 2.65. Hence, the C–H cleavage of benzyl alcohol should be included in the rate-determining step (RDS) [19].
Furthermore, the energy barriers for the dehydrogenation of benzyl alcohol (RDS) at different zinc sites were calculated according to the density functional theory (DFT). The order of energy barriers for the dehydrogenation of benzyl alcohol at different single Zn sites was ZnN3S < ZnN4 < ZnN4S, which was proportional to the Zn positive-charge density (Figure 5 and Figure S5). Therefore, the coordination environment of Zn sites was adjusted by rationally doping heteroatoms to obtain more electron-rich Zn single-atom sites, which could effectively improve the hydrogen-borrowing ability of Zn-SAC [26,54].

2.4. Recyclability of CNS@Zn1-AA

Finally, the recyclability of CNS@Zn1-AA was investigated under the optimized conditions (Figure 6). CNS@Zn1-AA was recycled by centrifugation, washed with EtOAc and directly used for the next run, and only a minor loss in yield was observed after eight runs. The TEM, HAADF-STEM and XRD results suggested that no obvious metal agglomeration was detected after eight runs (Figures S3 and S6).

3. Conclusions

In summary, a simple and scalable strategy was developed for preparing a ZIF-derived N, S-co-doped carbon-anchored Zn single-atom catalyst (CNS@Zn1-AA) by the ball-milling and pyrolysis processes. S-doping played a crucial role in the activity of this material: (1) It increased the defects and specific surface area of CNS@Zn1-AA; (2) it enhanced the electron density of Zn sites, thereby improving the catalytic activity of CNS@Zn1-AA, which was confirmed by both experimental and theoretical calculation results. This material exhibited excellent performance in the hydrogen auto-transfer alkylation of aromatic amines (120 °C, TOF up to 8.4 h−1). To the best of our knowledge, this is the first example of the Zn-SAC-catalyzed N-alkylation of aromatic amines via the hydrogen-borrowing strategy, in which inert aliphatic alcohols could be also applied. Furthermore, this catalyst showed excellent stability, and no significant activity degradation was observed after eight runs.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/nano13030445/s1. Figure S1: CN@Zn1-AA and CNS@Zn1-AA images of (a) Brunauer-Emmett-Teller (BET); (b) Barrett-Joyner-Halenda (BJH). Figure S2: The Raman spectra of CN@Zn1-AA (blue) and CNS@Zn1-AA (red). Figure S3: XRD image of CNS@Zn1-AA (red) and recycled CNS@Zn1-AA after 8 runs (green). Figure S4: XPS spectra of CNS@Zn1-AA. Figure S5: Partial reaction pathway and corresponding energies of ZnN3S, ZnN4S and ZnN4 for the N-alkylation of amines with benzyl alcohol. Figure S6: (a) TEM and (b) HAADF-STEM images of CNS@Zn1-AA recycled after 8 runs. Scheme S1: Reduction of o-hydroxychalcone with benzyl alcohol. Table S1: The BET surface areas and pore volumes of CN@Zn1-AA and CNS@Zn1-AA. Table S2: ICP result of CNS@Zn1-AA. Table S3: K-edge EXAFS fitting parameters of CNS@Zn1-AA catalyst (S02=0.700).

Author Contributions

Conceptualization, X.Z. and G.-P.L.; formal analysis, X.Z., J.R. and G.-P.L.; investigation, X.Z. and G.-P.L.; writing—original draft preparation, X.Z. and G.-P.L.; visualization, X.Z.; supervision, Q.Z., Y.L., Y.T., G.L. and P.W.; project administration, P.W. and G.-P.L. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

Not applicable.

Acknowledgments

We gratefully acknowledge the Fundamental Research Funds for the Central Universities (30920021120) and the National Natural Science Foundation of China (32001266) for financial support.

Conflicts of Interest

There are no conflict to declare.

References

  1. Ricci, A. Amino Group Chemistry: From Synthesis to the Life Sciences; Wiley-VCH: Weinheim, Germany, 2008. [Google Scholar]
  2. Leonard, J.; Blacker, A.J.; Marsden, S.P.; Jones, M.F.; Mulholland, K.R.; Newton, R. A survey of the borrowing hydrogen approach to the synthesis of some pharmaceutically relevant intermediates. Org. Process Res. Dev. 2015, 19, 1400–1410. [Google Scholar] [CrossRef]
  3. Huang, M.; Li, Y.; Liu, J.; Lan, X.B.; Liu, Y.; Zhao, C.; Ke, Z. A bifunctional strategy for N-heterocyclic carbene-stabilized iridium complex-catalyzed N-alkylation of amines with alcohols in aqueous media. Green Chem. 2019, 21, 219–224. [Google Scholar] [CrossRef]
  4. Yan, L.; Liu, X.X.; Fu, Y. N-Alkylation of amines with phenols over highly active heterogeneous palladium hydride catalysts. RSC Adv. 2016, 6, 109702–109705. [Google Scholar] [CrossRef]
  5. Bohm, H.J.; Banner, D.; Bendels, S.; Kansy, M.; Kuhn, B.; Muller, K.; Obst-Sander, U.; Stahl, M. Fluorine in medicinal chemistry. ChemBioChem 2004, 5, 637–643. [Google Scholar] [CrossRef] [PubMed]
  6. Barta, K.; Ford, P.C. Catalytic conversion of nonfood woody biomass solids to organic liquids. Acc. Chem. Res. 2014, 47, 1503–1512. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  7. Meng, S.S.; Tang, X.; Luo, X.; Wu, R.; Zhao, J.L.; Chan, A.S.C. Borane-Catalyzed Chemoselectivity-controllable N-alkylation and ortho C-alkylation of unprotected arylamines using benzylic alcohols. ACS Catal. 2019, 9, 8397–8403. [Google Scholar] [CrossRef]
  8. Niu, F.; Wang, Q.Y.; Yan, Z.; Kusema, B.T.; Khodakov, A.Y.; Ordomsky, V.V. Highly efficient and selective N-Alkylation of amines with alcohols catalyzed by in situ rehydrated titanium hydroxide. ACS Catal. 2020, 10, 3404–3414. [Google Scholar] [CrossRef]
  9. Sun, K.K.; Shan, H.B.; Lu, G.P.; Cai, C.; Beller, M. Synthesis of N-heterocycles via oxidant-free dehydrocyclization of alcohols using heterogeneous catalysts. Angew. Chem. Int. Ed. Engl. 2021, 60, 25188–25202. [Google Scholar] [CrossRef]
  10. Cui, X.J.; Deng, Y.Q.; Shi, F. Reductive N-alkylation of nitro compounds to N-alkyl and N,N-dialkyl amines with glycerol as the hydrogen source. ACS Catal. 2013, 3, 808–811. [Google Scholar] [CrossRef]
  11. Wong, C.M.; Peterson, M.B.; Pernik, I.; McBurney, R.T.; Messerle, B.A. Highly efficient Rh(I) homo- and heterogeneous catalysts for C–N couplings via hydrogen borrowing. Inorg. Chem. 2017, 56, 14682–14687. [Google Scholar] [CrossRef]
  12. Wong, C.M.; McBurney, R.T.; Binding, S.C.; Peterson, M.B.; Gonçales, V.R.; Gooding, J.J.; Messerle, B.A. Iridium(III) homo- and heterogeneous catalysed hydrogen borrowing C–N bond formation. Green Chem. 2017, 19, 3142–3151. [Google Scholar] [CrossRef]
  13. Abdukader, A.; Jin, H.; Cheng, Y.; Zhu, C. Rhenium-catalyzed amination of alcohols by hydrogen transfer process. Tetrahedron Lett. 2014, 55, 4172–4174. [Google Scholar] [CrossRef]
  14. Shimizu, K.; Nishimura, M.; Satsuma, A. γ-Alumina-Supported Silver Cluster for N-Benzylation of Anilines with Alcohols. ChemCatChem 2009, 1, 497–503. [Google Scholar] [CrossRef]
  15. He, L.; Lou, X.B.; Ni, J.; Liu, Y.M.; Cao, Y.; He, H.Y.; Fan, K.N. Efficient and clean gold-catalyzed one-pot selective N-alkylation of amines with alcohols. Chem. Eur. J. 2010, 16, 13965–13969. [Google Scholar] [CrossRef] [PubMed]
  16. He, W.; Wang, L.D.; Sun, C.L.; Wu, K.K.; He, S.B.; Chen, J.P.; Wu, P.; Yu, Z.K. Pt–Sn/g-Al2O3-Catalyzed Highly Efficient Direct Synthesis of Secondary and Tertiary Amines and Imines. Chem. Eur. J. 2011, 17, 13308–13317. [Google Scholar] [CrossRef]
  17. Rawlings, A.J.; Diorazio, L.J.; Wills, M. C–N bond formation between alcohols and amines using an iron cyclopentadienone catalyst. Org. Lett. 2015, 17, 1086–1089. [Google Scholar] [CrossRef]
  18. Nallagangula, M.; Sujatha, C.; Bhat, V.T.; Namitharan, K. A nanoscale iron catalyst for heterogeneous direct N- and C-alkylations of anilines and ketones using alcohols under hydrogen autotransfer conditions. Chem. Commun. 2019, 55, 8490–8493. [Google Scholar] [CrossRef]
  19. Lu, G.P.; Shan, H.B.; Lin, Y.M.; Zhang, K.; Zhou, B.J.; Zhong, Q.; Wang, P.C. A Fe single atom on N,S-doped carbon catalyst for performing N-alkylation of aromatic amines under solvent-free conditions. J. Mater. Chem. A 2021, 9, 25128–25135. [Google Scholar] [CrossRef]
  20. Ma, Z.; Zhou, B.; Li, X.; Kadam, R.G.; Gawande, M.B.; Petr, M.; Zboril, R.; Beller, M.; Jagadeesh, R.V. Reusable Co-nanoparticles for general and selective N-alkylation of amines and ammonia with alcohols. Chem. Sci. 2022, 13, 111–117. [Google Scholar] [CrossRef]
  21. Afanasenko, A.; Elangovan, S.; Stuart, M.C.A.; Bonura, G.; Frusteri, F.; Barta, K. Efficient nickel-catalysed N-alkylation of amines with alcohols. Catal. Sci. Technol. 2018, 8, 5498–5505. [Google Scholar] [CrossRef]
  22. Bains, A.K.; Kundu, A.; Yadav, S.; Adhikari, D. Borrowing hydrogen-mediated N-alkylation reactions by a well-defined homogeneous nickel catalyst. ACS Catal. 2019, 9, 9051–9059. [Google Scholar] [CrossRef]
  23. Dixit, M.; Mishra, M.; Joshi, P.A.; Shah, D.O. Clean borrowing hydrogen methodology using hydrotalcite supported copper catalyst. Catal. Commun. 2013, 33, 80–83. [Google Scholar] [CrossRef]
  24. Rojas-Buzo, S.; Concepción, P.; Corma, A.; Moliner, M.; Boronat, M. In-situ-generated active Hf-hydride in zeolites for the tandem N-alkylation of amines with benzyl alcohol. ACS Catal. 2021, 11, 8049–8061. [Google Scholar] [CrossRef]
  25. Kallmeier, F.; Fertig, R.; Irrgang, T.; Kempe, R. Chromium-catalyzed alkylation of amines by alcohols. Angew. Chem. Int. Ed. 2020, 59, 11789–11793. [Google Scholar] [CrossRef] [PubMed]
  26. Huang, M.; Li, Y.K.; Li, Y.W.; Liu, J.H.; Shu, S.W.; Liu, Y.; Ke, Z.F. Room temperature N-heterocyclic carbene manganese catalyzed selective N-alkylation of anilines with alcohols. Chem. Commun. 2019, 55, 6213–6216. [Google Scholar] [CrossRef]
  27. Homberg, L.; Roller, A.; Hultzsch, K.C. A Highly active PN3 manganese pincer complex performing N-alkylation of amines under mild conditions. Org. Lett. 2019, 21, 3142–3147. [Google Scholar] [CrossRef] [PubMed]
  28. Li, W.; Huang, M.; Liu, J.; Huang, Y.L.; Lan, X.B.; Ye, Z.; Zhao, C.; Liu, Y.; Ke, Z. Enhanced hydride donation achieved molybdenum catalyzed direct N-alkylation of anilines or nitroarenes with alcohols: From computational design to experiment. ACS Catal. 2021, 11, 10377–10382. [Google Scholar] [CrossRef]
  29. Sankar, V.; Kathiresan, M.; Sivakumar, B.; Mannathan, S. Zinc-catalyzed N-alkylation of aromatic amines with alcohols: A ligand-free approach. Adv. Synth. Catal. 2020, 362, 4409–4414. [Google Scholar] [CrossRef]
  30. Zhang, X.P.; Lu, G.P.; Wang, K.; Lin, Y.M.; Wang, P.C.; Yi, W.B. Lignin-derived Zn single atom/N-codoped porous carbon for α-alkylation of aromatic ketones with alcohols via borrowing hydrogen strategy. Nano Res. 2022, 15, 1874–1881. [Google Scholar] [CrossRef]
  31. Wan, J.; Zhao, Z.; Shang, H.; Peng, B.; Chen, W.; Pei, J.; Zheng, L.; Dong, J.; Cao, R.; Sarangi, R.; et al. In situ phosphatizing of triphenylphosphine encapsulated within metal–organic frameworks to design atomic Co1–P1N3 interfacial structure for promoting catalytic performance. J. Am. Chem. Soc. 2020, 142, 8431–8439. [Google Scholar] [CrossRef]
  32. Long, X.; Li, Z.; Gao, G.; Sun, P.; Wang, J.; Zhang, B.; Zhong, J.; Jiang, Z.; Li, F. Graphitic phosphorus coordinated single Fe atoms for hydrogenative transformations. Nat. Commun. 2020, 11, 4074. [Google Scholar] [CrossRef] [PubMed]
  33. Buchwalter, P.; Rose, J.; Braunstein, P. Multimetallic catalysis based on heterometallic complexes and clusters. Chem. Rev. 2015, 115, 28–126. [Google Scholar] [CrossRef] [PubMed]
  34. Li, H.; Wang, S.; Sawada, H.; Han, G.G.; Samuels, T.; Allen, C.S.; Kirkland, A.I.; Grossman, J.C.; Warner, J.H. Atomic structure and dynamics of single platinum atom interactions with monolayer MoS2. ACS Nano 2017, 11, 3392–3403. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  35. An, S.; Zhang, G.; Wang, T.; Zhang, W.; Li, K.; Song, C.; Miller, J.T.; Miao, S.; Wang, J.; Guo, X. High-density ultra-small clusters and single-atom Fe sites embedded in graphitic carbon nitride (g-C3N4) for highly efficient catalytic advanced oxidation processes. ACS Nano 2018, 12, 9441–9450. [Google Scholar] [CrossRef] [PubMed]
  36. Gu, J.; Hsu, C.S.; Bai, L.C.; Chen, H.M.; Hu, X.L. Atomically dispersed Fe3+ sites catalyze efficient CO2 electroreduction to CO. Science 2019, 364, 1091–1094. [Google Scholar] [CrossRef] [PubMed]
  37. Koshy, D.M.; Chen, S.C.; Lee, D.U.; Stevens, M.B.; Abdellah, A.M.; Dull, S.M.; Chen, G.; Nordlund, D.; Gallo, A.; Hahn, C.; et al. Understanding the origin of highly selective CO2 electroreduction to CO on Ni, N-doped carbon catalysts. Angew. Chem. Int. Ed. 2020, 59, 4043–4050. [Google Scholar] [CrossRef]
  38. Ju, W.; Bagger, A.; Hao, G.P.; Varela, A.S.; Sinev, I.; Bon, V.; Cuenya, B.; Roldan, B.; Kaskel, S.; Rossmeisl, J.; et al. Understanding activity and selectivity of metal-nitrogen-doped carbon catalysts for electrochemical reduction of CO2. Nat. Commun. 2017, 8, 944. [Google Scholar] [CrossRef] [Green Version]
  39. Tan, H.Y.; Lin, S.C.; Wang, J.; Chang, C.J.; Haw, S.C.; Lin, K.H.; Tsai, L.D.; Chen, H.C.; Chen, H.M. MOF-templated sulfurization of atomically dispersed manganese catalysts facilitating electroreduction of CO2 to CO. ACS Appl. Mater. Interfaces 2021, 13, 52134–52143. [Google Scholar] [CrossRef]
  40. Ji, S.; Chen, Y.; Wang, X.; Zhang, Z.; Wang, D.; Li, Y. Chemical synthesis of single atomic sitecatalysts. Chem. Rev. 2020, 120, 11900–11955. [Google Scholar] [CrossRef]
  41. Qin, R.; Liu, K.; Wu, Q.; Zheng, N. Surface coordination chemistry of atomically dispersed metal catalysts. Chem. Rev. 2020, 120, 11810–11899. [Google Scholar] [CrossRef]
  42. Zhang, N.; Ye, C.; Yan, H.; Li, L.; He, H.; Wang, D.; Li, Y. Single-atom site catalysts for environmental catalysis. Nano Res. 2020, 13, 3165–3182. [Google Scholar] [CrossRef]
  43. Sun, K.K.; Shan, H.B.; Ma, R.; Wang, P.; Neumann, H.; Lu, G.P.; Beller, M. Catalytic oxidative dehydrogenation of N-heterocycles with nitrogen/phosphorus co-doped porous carbon materials. Chem. Sci. 2022, 13, 6865–6872. [Google Scholar] [CrossRef] [PubMed]
  44. Su, T.Y.; Lu, G.P.; Sun, K.K.; Zhang, M.; Cai, C. ZIF-derived metal/N-doped porous carbon nanocomposites: Efficient catalysts for organic transformations. Catal. Sci. Technol. 2022, 12, 2106–2121. [Google Scholar] [CrossRef]
  45. Sun, K.K.; Chen, S.J.; Li, Z.L.; Lu, G.P.; Cai, C. Synthesis of a ZIF-derived hollow yolk–shell Co@CN catalyst for the oxidative esterification of 5-hydroxymethylfurfural. Green Chem. 2019, 21, 1602–1608. [Google Scholar] [CrossRef]
  46. Sun, K.K.; Sun, J.L.; Lu, G.P.; Cai, C. Enhanced catalytic activity of cobalt nanoparticles encapsulated with an N-doped porous carbon shell derived from hollow ZIF-8 for efficient synthesis of nitriles from primary alcohols in water. Green Chem. 2019, 21, 4334–4340. [Google Scholar] [CrossRef]
  47. Han, J.X.; Meng, X.Y.; Lu, L.; Bian, J.J.; Li, Z.P.; Sun, C.W. Single-atom Fe-Nx-C as an efficient electrocatalyst for zinc–air batteries. Adv. Funct. Mater. 2019, 29, 1808872. [Google Scholar] [CrossRef]
  48. Lu, G.P.; Sun, K.K.; Lin, Y.M.; Du, Q.; Zhang, J.; Wang, K.; Wang, P.C. Single-atomic-site iron on N-doped carbon for chemoselective reduction of nitroarenes. Nano Res. 2022, 15, 603–611. [Google Scholar] [CrossRef]
  49. Xu, X.; Zhang, X.; Xia, Z.; Sun, R.; Li, H.; Wang, J.; Yu, S.; Wang, S.; Sun, G. Solid phase microwave-assisted fabrication of Fe-doped ZIF-8 for single-atom Fe-N-C electrocatalysts on oxygen reduction. J. Energy Chem. 2021, 54, 579–586. [Google Scholar] [CrossRef]
  50. Lin, Y.M.; Yu, J.; Zhang, X.; Fang, J.K.; Lu, G.P.; Huang, H. Carbohydrate-derived porous carbon materials: An ideal platform for green organic synthesis. Chin. Chem. Lett. 2022, 33, 186–196. [Google Scholar] [CrossRef]
  51. Rui, T.; Lu, G.P.; Zhao, X.; Cao, X.; Chen, Z. The synergistic catalysis on Co nanoparticles and CoNx sites of aniline-modified ZIF derived Co@NCs for oxidative esterification of HMF. Chin. Chem. Lett. 2021, 32, 685–690. [Google Scholar] [CrossRef]
  52. Sun, K.K.; Shan, H.; Neumann, H.; Lu, G.P.; Beller, M. Efficient iron single-atom catalysts for selective ammoxidation of alcohols to nitriles. Nat. Commun. 2022, 13, 1848. [Google Scholar] [CrossRef] [PubMed]
  53. Avci, C.; Ariñez-Soriano, J.; Carné-Sánchez, A.; Guillerm, V.; Carbonell, C.; Imaz, I.; Maspoch, D. Post-synthetic anisotropic wet-chemical etching of colloidal sodalite ZIF crystals. Angew. Chem. Int. Ed. 2015, 54, 14417–14421. [Google Scholar] [CrossRef] [PubMed]
  54. Qi, Z.; Hu, C.; Zhong, Y.; Cai, C.; Lu, G.P. The ammoxidation of alcohols over heterogeneous catalysts for the green synthesis of nitriles. Org. Chem. Front. 2021, 8, 3137–3149. [Google Scholar] [CrossRef]
  55. Cai, J.J.; Zhou, Q.Y.; Gong, X.F.; Liu, B.; Zhang, Y.L.; Dai, Y.K.; Gu, D.M.; Zhao, L.; Sui, X.L.; Wang, Z.B. Metal-free amino acid glycine-derived nitrogen-doped carbon aerogel with superhigh surface area for highly efficient Zn-air batteries. Carbon 2020, 167, 75–84. [Google Scholar] [CrossRef]
  56. Lee, J.S.; Rajan, H.; Christy, M.; Yi, S.C. Optimization of active sites by sulfurization of the core–shell ZIF-67@ZIF-8 for rapid oxygen reduction kinetics in acidic media. Int. J. Hydrogen Energy 2021, 46, 10739–10748. [Google Scholar] [CrossRef]
  57. Yang, F.; Song, P.; Liu, X.; Mei, B.; Xing, W.; Jiang, Z.; Gu, L.; Xu, W. Highly efficient CO2 electroreduction on ZnN4-based single-atom catalyst. Angew. Chem. Int. Ed. 2018, 57, 12303–12307. [Google Scholar] [CrossRef]
  58. Dai, C.; Li, R.; Guo, H.; Liang, S.; Shen, H.; Thomas, T.; Yang, M. Nitrogen, sulfur co-doped carbon coated zinc sulfide for efficient hydrogen peroxide electrosynthesis. Dalton Trans. 2021, 50, 5416–5419. [Google Scholar] [CrossRef]
  59. Liu, F.; Meng, J.; Jiang, G.; Li, J.; Wang, H.; Xiao, Z.; Yu, R.; Mai, L.; Wu, J. Coordination engineering of metal single atom on carbon for enhanced and robust potassium storage. Matter 2021, 4, 4006–4021. [Google Scholar] [CrossRef]
  60. Delley, B. From molecules to solids with the DMol3 approach. J. Chem. Phys. 2000, 113, 7756–7764. [Google Scholar] [CrossRef]
  61. Perdew, J.P.; Burke, K.; Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 1996, 77, 3865–3868. [Google Scholar] [CrossRef]
  62. Halgren, T.A.; Lipscomb, W.N. The synchronous-transit method for determining reaction pathways and locating molecular transition states. Chem. Phys. Lett. 1977, 49, 225–232. [Google Scholar] [CrossRef]
  63. Fang, M.; Wang, X.; Li, X.; Zhu, Y.; Xiao, G.; Feng, J.; Jiang, X.; Lv, K.; Zhu, Y.; Lin, W.F. Curvature-induced Zn 3d electron return on Zn−N4 single-atom carbon nanofibers for boosting electroreduction of CO2. ChemCatChem 2021, 13, 603–609. [Google Scholar] [CrossRef]
  64. Wang, N.; Liu, Z.; Ma, J.; Liu, J.; Zhou, P.; Chao, Y.; Ma, C.; Bo, X.; Liu, J.; Hei, Y.; et al. Sustainability perspective-oriented synthetic strategy for zinc single-atom catalysts boosting electrocatalytic reduction of carbon dioxide and oxygen. ACS Sustain. Chem. Eng. 2020, 8, 13813–13822. [Google Scholar] [CrossRef]
  65. Wang, J.; Li, H.; Liu, S.; Hu, Y.; Zhang, J.; Xia, M.; Hou, Y.; Tse, J.; Zhang, J.; Zhao, Y. Turning on Zn 4s electrons in a N2-Zn-B2 configuration to stimulate remarkable ORR performance. Angew. Chem. Int. Ed. Engl. 2021, 60, 181–185. [Google Scholar] [CrossRef] [PubMed]
  66. Shen, B.; He, Q.; Dong, S.; Liu, X.; Feng, X. A chiral cobalt(ii) complex catalyzed enantioselective aza-Piancatelli rearrangement/Diels–Alder cascade reaction. Chem. Sci. 2020, 11, 3862–3867. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  67. Marin, L.; Force, G.; Gandon, V.; Schulz, E.; Lebœuf, D. Aza-piancatelli cyclization as a platform for the preparation of scaffolds of natural compounds: Application to the total synthesis of bruceolline D. Eur. J. Org. Chem. 2020, 33, 5323–5328. [Google Scholar] [CrossRef]
  68. Zaytsev, V.P.; Mertsalov, D.F.; Trunova, A.M.; Khanova, A.V.; Nikitina, E.V.; Sinelshchikova, A.A.; Grigoriev, M.S. Iodine acetate as a mild selective agent for the Wagner–Meerwein earrangement in 3a,6-Epoxyisoindoles. Chem. Heterocycl. Compd. 2020, 56, 930–935. [Google Scholar] [CrossRef]
  69. Sergio, R.B.; Pilar, G.G.; Avelino, C. Catalytic transfer hydrogenation of biomass-derived carbonyls over hafnium-based metal–organic frameworks. ChemSusChem 2018, 11, 432–438. [Google Scholar]
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Figure 1. The development of the catalysts for the N-alkylation of amines. TOF is the turnover frequency. Refs. [10,11,12,14,15,16,17,18,20,21,23,24,25,28,29].
Figure 1. The development of the catalysts for the N-alkylation of amines. TOF is the turnover frequency. Refs. [10,11,12,14,15,16,17,18,20,21,23,24,25,28,29].
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Scheme 1. Schematic illustration of the synthesis process of CNS@Zn1-AA.
Scheme 1. Schematic illustration of the synthesis process of CNS@Zn1-AA.
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Figure 2. (a) ZIF-8-AA@S; (b) ZIF-8-An@S; (c) ZIF-8-Am@S; (d) ZIF-8@S; (e) XRD patterns of ZIFs.
Figure 2. (a) ZIF-8-AA@S; (b) ZIF-8-An@S; (c) ZIF-8-Am@S; (d) ZIF-8@S; (e) XRD patterns of ZIFs.
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Figure 3. (a) TEM; (b) HAADF-STEM images of CNS@Zn1-AA. (c–f) The EDX elemental mapping images of N, S and Zn of CNS@Zn1-AA.
Figure 3. (a) TEM; (b) HAADF-STEM images of CNS@Zn1-AA. (c–f) The EDX elemental mapping images of N, S and Zn of CNS@Zn1-AA.
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Figure 4. (a) Zn K-edge XANES spectra. (b) FT EXAFS spectra. (c) EXAFS curve-fitting of CNS@Zn1-AA in R space.
Figure 4. (a) Zn K-edge XANES spectra. (b) FT EXAFS spectra. (c) EXAFS curve-fitting of CNS@Zn1-AA in R space.
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Scheme 2. Substrate scope of the N-alkylation of amines with alcohols. a Reaction conditions: 1 (1 mmol), 2 (2 mmol), base (0.3 eq.), CNS@Zn1-AA (15 mg), toluene (2 mL), Ar, 120 °C, 12 h. b The yield was determined by GC using anisole as the internal standard. c 140 °C.
Scheme 2. Substrate scope of the N-alkylation of amines with alcohols. a Reaction conditions: 1 (1 mmol), 2 (2 mmol), base (0.3 eq.), CNS@Zn1-AA (15 mg), toluene (2 mL), Ar, 120 °C, 12 h. b The yield was determined by GC using anisole as the internal standard. c 140 °C.
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Scheme 3. The H/D kinetic isotope effect (KIE) experiment. Reaction conditions: 1a (1 mmol), 2a or PhCD2OH (2 mmol), KOH (0.3 eq.), CNS@Zn1-AA (15 mg), Ar, 120 °C, 4 h.
Scheme 3. The H/D kinetic isotope effect (KIE) experiment. Reaction conditions: 1a (1 mmol), 2a or PhCD2OH (2 mmol), KOH (0.3 eq.), CNS@Zn1-AA (15 mg), Ar, 120 °C, 4 h.
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Figure 5. (a) Partial reaction pathway and corresponding energies of ZnN4S, ZnN4 and ZnN3S for the N-alkylation of amines with benzyl alcohol. (b) Plots of the valence state of the Zn charge. Black, white, yellow, blue, red and light blue circles represent carbon, hydrogen, sulfur, nitrogen, oxygen and zinc atoms, respectively.
Figure 5. (a) Partial reaction pathway and corresponding energies of ZnN4S, ZnN4 and ZnN3S for the N-alkylation of amines with benzyl alcohol. (b) Plots of the valence state of the Zn charge. Black, white, yellow, blue, red and light blue circles represent carbon, hydrogen, sulfur, nitrogen, oxygen and zinc atoms, respectively.
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Figure 6. Recyclability of CNS@Zn1-AA. Reaction conditions: 1a (2 mmol), 2a (4 mmol), KOH (0.6 mmol), CNS@Zn1-AA (30 mg), toluene (3 mL), Ar, 120 °C, 6 h.
Figure 6. Recyclability of CNS@Zn1-AA. Reaction conditions: 1a (2 mmol), 2a (4 mmol), KOH (0.6 mmol), CNS@Zn1-AA (30 mg), toluene (3 mL), Ar, 120 °C, 6 h.
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Table
Table 1. The naming rules of the ZIFs and Zn@NCs.
Table 1. The naming rules of the ZIFs and Zn@NCs.
EntryZIFsZn@NCs aNote
1ZIF-8-AA@SCNS@Zn1-AA b-
2ZIF-8-An@S cCNS@Zn1-AnOnly use of 2-MI and aniline d
3ZIF-8-Am@S eCNS@Zn1-AmOnly use of 2-MI and ammonia
4ZIF-8@SCNS@Zn1Only use of 2-MI
5ZIF-8-AACN@Zn1-AA-
a NC is N-doped carbon. b Molar ratio of S/Zn = 1; CNS is N, S-doped carbon and AA is ammonia and aniline. c An is aniline. d 2-MI is methylimidazole. e Am is ammonia.
Table
Table 2. Optimization of reaction conditions a.
Table 2. Optimization of reaction conditions a.
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EntryCatalystBaseYield (%) b
3a4a
1-KOH54
2CNS@Zn1-AA-811
3CNS@Zn1-AAKOH902
4nano ZnKOH134
5ZnOKOH89
6Zn(NO)3.6H2OKOH1215
7CN@Zn1-AAKOH3413
8CNS@Zn1-AmKOH56
9CNS@Zn1-AnKOH68
10 cCNS@Zn1-AAKOH922
11CNS@Zn1-AANaOH467
12CNS@Zn1-AANa2CO3911
13CNS@Zn1-AAKOtBu710
a Reaction conditions: 1a (1 mmol), 2a (2 mmol), base (0.3 eq.), catalyst (15 mg), toluene (2 mL), Ar, 120 °C, 12 h. b The yield was determined by GC using anisole as the internal standard. c 18 h.
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Zhang, X.; Zhang, Q.; Reng, J.; Lin, Y.; Tang, Y.; Liu, G.; Wang, P.; Lu, G.-P. N, S Co-Coordinated Zinc Single-Atom Catalysts for N-Alkylation of Aromatic Amines with Alcohols: The Role of S-Doping in the Reaction. Nanomaterials 2023, 13, 445. https://doi.org/10.3390/nano13030445

AMA Style

Zhang X, Zhang Q, Reng J, Lin Y, Tang Y, Liu G, Wang P, Lu G-P. N, S Co-Coordinated Zinc Single-Atom Catalysts for N-Alkylation of Aromatic Amines with Alcohols: The Role of S-Doping in the Reaction. Nanomaterials. 2023; 13(3):445. https://doi.org/10.3390/nano13030445

Chicago/Turabian Style

Zhang, Xueping, Qiang Zhang, Jiacheng Reng, Yamei Lin, Yongxing Tang, Guigao Liu, Pengcheng Wang, and Guo-Ping Lu. 2023. "N, S Co-Coordinated Zinc Single-Atom Catalysts for N-Alkylation of Aromatic Amines with Alcohols: The Role of S-Doping in the Reaction" Nanomaterials 13, no. 3: 445. https://doi.org/10.3390/nano13030445

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