分级结构碳纳米笼高效催化苄胺氧化偶联制N-苄烯丁胺

doi:10.6023/A20110527

摘要/Abstract

苄胺氧化偶联制N-苄烯丁胺通常需使用贵金属催化剂, 开发廉价催化剂具有重要研究价值. 本工作以具有大比表面积和丰富表面缺陷的分级结构碳纳米笼(hCNCs)作为无金属催化剂, 在无溶剂、100 ℃和常压O₂条件下即可实现苄胺到N-苄烯丁胺的高效转化, 反应8 h的苄胺转化率和N-苄烯丁胺选择性均可达98%, 远优于碳纳米管、还原氧化石墨烯、活性炭等典型碳材料. hCNC700样品循环使用6次后催化性能基本无衰减, 且具有优秀的底物拓展性. hCNC700的优异催化性能源于其超高的比表面积可提供大量的缺陷活性位点, 而独特的分级孔结构十分有利于反应过程中的传质, 使丰富的表面活性位点(缺陷)得以充分利用.

关键词: 分级结构碳纳米笼, 无金属催化剂, 缺陷催化, 苄胺, N-苄烯丁胺

N-Benzylidene benzylamine is an important pharmaceutical intermediate and industrial chemical. Traditionally, it is synthesized via the reaction between benzylamine and benzaldehyde by using Lewis acid catalysts, which usually suffers from the difficulty of product separation and environmental unfriendliness. An alternative approach is the oxidative coupling of benzylamine catalyzed by metal-based catalysts, which is also beset by the contamination of metallic impurities. Thus, the development of green, metal-free and reusable heterogeneous catalysts is highly attractive. Herein, we report an efficient metal-free catalyst, hierarchical carbon nanocages (hCNCs) synthesized by the in-situ magnesium oxide template method with benzene precursor at different temperatures (700, 800 and 900 ℃), for the oxidative coupling of benzylamine to N-benzylidene benzylamine. The hCNCs feature multi-scale hierarchical pore structure, high specific surface area and abundant surface defects. The hCNC700 exhibits excellent catalytic performance for the solvent-free oxidative coupling of benzylamine to N-benzylidene benzylamine under mild conditions (100 ℃, atmospheric O₂). Specifically, after reacting for 8 h, both benzylamine conversion and N-benzylidene benzylamine selectivity are larger than 98%, far better than the counterparts of carbon nanotubes, reduced graphene oxide and activated carbon, as well as the reported mesoporous carbon and graphene oxide. The hCNC700 also presents high mass activity, significantly better than the reported carbon-based catalysts. Its catalytic performance is almost unattenuated after 6 times of recycling, exhibiting good stability. By comparison experiments, the catalytic activity of hCNCs results from the intrinsic defects of carbon, and the excellent performance of hCNC700 is mainly attributed to the following aspects: (i) its ultra-high specific surface area can provide abundant surface active sites (defects), (ii) the unique hierarchical pore structure is very conducive to mass transfer in the reaction process, enabling the full utilization of these active sites. In addition, hCNC700 shows good catalytic performance for different substrates, with high catalytic activity (>90% conversion rate for 12 h reaction) and high selectivity (>95%) for oxidative coupling of aromatic methylene amines. This study provides a new avenue for the development of cheap and efficient carbon-based metal-free catalysts.

Key words: hierarchical carbon nanocage, metal-free catalyst, defect catalysis, benzylamine, N-benzylidene benzylamine

引用此文

曾誉, 吕品, 蔡跃进, 高福杰, 卓欧, 吴强, 杨立军, 王喜章, 胡征. 分级结构碳纳米笼高效催化苄胺氧化偶联制N-苄烯丁胺[J]. 化学学报, 2021, 79(4): 539-544.

Yu Zeng, Pin Lyu, Yuejin Cai, Fujie Gao, Ou Zhuo, Qiang Wu, Lijun Yang, Xizhang Wang, Zheng Hu. Hierarchical Carbon Nanocages as Efficient Catalysts for Oxidative Coupling of Benzylamine to N-Benzylidene Benzylamine[J]. Acta Chimica Sinica, 2021, 79(4): 539-544.

导出引用 EndNote|Reference Manager|ProCite|BibTeX|RefWorks

分享此文

图/表 5

图1. hCNCs的SEM及TEM表征. (a)典型的SEM照片; (b~d)分别为 hCNC700、hCNC800和hCNC900的TEM照片. 插图为高分辨TEM照片.

Figure 1. SEM and TEM characterizations of hCNCs. (a) Typical SEM image; (b~d) TEM images of hCNC700, hCNC800 and hCNC900, respectively. Insets are high-resolution TEM images.

图2. hCNCs系列样品的Raman表征结果. (a) Raman光谱; (b, d) ID/IG随hCNCs制备温度(b)和退火温度(d)的变化关系; (c, e) D带和G带半峰宽随hCNCs制备温度(c)和退火温度(e)的变化关系.

Figure 2. Raman characterizations of hCNCs. (a) Raman spectra; (b, d) ID/IG versus synthesis and annealing temperatures of hCNCs, respectively; (c, e) FWHMs of D- and G-band versus synthesis and annealing temperatures of hCNCs, respectively.

图3. hCNCs系列催化剂的苄胺氧化偶联催化性能对比. (a) hCNC700与几种典型碳材料(rGO、CNT、XC-72及AC)的苄胺转换频率(TOF)对比. 文献[14⇓⇓-17]碳基无金属催化剂的相应数据供参考; (b) hCNC700的循环稳定性; (c) hCNC700、hCNC800、hCNC900和hCNC700-C反应8 h后的转化率; (d) hCNC700及经不同温度退火后的hCNC700的转化率随时间变化曲线. 插图为对快速反应阶段进行线性拟合所得斜率k值与ID/IG的关系.

Figure 3. Comparison of catalytic performance of hCNCs for the oxidative coupling of benzylamine. (a) Comparison of the turnover frequency (TOF) of benzylamine for hCNC700 and several typical carbon-based materials (rGO, CNT, XC-72 and AC). The data for the carbon-based metal-free catalysts from Refs [14⇓⇓-17] are also listed for reference; (b) cycling stability of hCNC700; (c) benzylamine conversions of hCNC700, hCNC800, hCNC900 and hCNC700-C after reacting for 8 h; (d) benzylamine conversions of the as-prepared hCNC700 and the annealed hCNC700 at different temperatures versus time. Inset is the curve of k versus ID/IG, here k is the linearly-fitted slope in the fast reaction period marked in (d).

Catalyst	Conversion/ %	Selectivity/ %	S_BET^b/ (m²•g^–1)	S_total^c/ m²	Mass/ mg
Blank	0	—	—	—	—
hCNC700	98	>98	2300	46.0	20.0
rGO	70	>95	2000	40.0	20.0
CNT	22	>98	230	46.0	200
XC-72	20	>98	300	42.0	140
AC	8	>98	150	42.0	280

表1. hCNC700与其他典型碳基无金属催化剂对苄胺氧化偶联制N-苄烯丁胺的催化性能对比a

Table 1. Comparison of catalytic performance of hCNC700 and other typical carbon-based metal-free catalysts for the oxidative coupling of benzylamine to N-benzylidene benzylamine

底物	产物	转化率/%
		98
		96
		97
		95
		90
		40
		15

表2. hCNC700催化选择性氧化不同取代基亚甲基胺的性能a

Table 2. Catalytic performance of selective oxidation of substituted methylene amine with hCNC700

参考文献 39

[1]	Chen, B.; Wang, L.; Gao, S. ACS Catal. 2015, 5,5851.
[2]	Qin, J.; Long, Y.; Wu, W.; Zhang, W.; Gao, Z.; Ma, J. J. Catal. 2019, 371,161.
[3]	Cao, X.; Qin, J.; Gou, G.; Li, J.; Wu, W.; Luo, S.; Luo, Y.; Dong, Z.; Ma, J.; Long, Y. Appl. Catal. B Environ. 2020, 272,118958.
[4]	Reeves, J.T.; Visco, M.D.; Marsini, M.A.; Grinberg, N.; Busacca, C.A.; Mattson, A.E.; Senanayake, C.H. Org. Lett. 2015, 17,2442.
[5]	Furukawa, S.; Suga, A.; Komatsu, T. ACS Catal. 2015, 5,1214.
[6]	He, W.; Wang, L.; Sun, C.; Wu, K.; He, S.; Chen, J.; Wu, P.; Yu, Z. Chem. Eur. J. 2011, 17,13308.
[7]	Mielby, J.; Poreddy, R.; Engelbrekt, C.; Kegnæs, S. Chin. J. Catal. 2014, 35,670.
[8]	Zhang, L.L.; Wang, W.T.; Wang, A.Q.; Cui, Y.T.; Yang, X.F.; Huang, Y.Q.; Liu, X.Y.; Liu, W.G.; Son, J.Y.; Oji, H.; Zhang, T. Green Chem. 2013, 15,2680.
[9]	Gong, K.P.; Du, F.; Xia, Z.H.; Durstock, M.; Dai, L.M. Science 2009, 323,760.
[10]	Yang, L.J.; Shui, J.L.; Du, L.; Shao, Y.Y.; Liu, J.; Dai, L.M.; Hu, Z. Adv. Mater. 2019, 31,1804799.
[11]	Zheng, Y.; Jiao, Y.; Zhu, Y.; Li, L.H.; Han, Y.; Chen, Y.; Du, A.; Jaroniec, M.; Qiao, S.Z. Nat. Commun. 2014, 5,3783.
[12]	Jiao, Y.; Zheng, Y.; Davey, K.; Qiao, S.Z. Nat. Energy 2016, 1,16130.
[13]	Zhang, J.; Liu, X.; Blume, R.; Zhang, A.; Schlögl, R.; Su, D.S. Science 2008, 322,73.
[14]	Yu, H.; Peng, F.; Tan, J.; Hu, X.; Wang, H.; Yang, J.; Zheng, W. Angew. Chem. Int. Ed. 2011, 50,3978.
[15]	Wen, G.; Wu, S.; Li, B.; Dai, C.; Su, D.S. Angew. Chem. Int. Ed. 2015, 54,4105.
[16]	Yang, S.L.; Peng, L.; Huang, P.P.; Wang, X.S.; Sun, Y.B.; Cao, C.Y.; Song, W.G. Angew. Chem. Int. Ed. 2016, 55,4016.
[17]	Su, C.L.; Acik, M.; Takai, K.; Lu, J.; Hao, S.J.; Zheng, Y.; Wu, P.P.; Bao, Q.L.; Enoki, T.; Chabal, Y.J.; Loh, K.P. Nat. Commun. 2012, 3,9.
[18]	Chen, B.; Wang, L.Y.; Dai, W.; Shang, S.S.; Lv, Y.; Gao, S. ACS Catal. 2015, 5,2788.
[19]	Wang, K.Z.; Jiang, P.B.; Yang, M.; Ma, P.; Qin, J.H.; Huang, X.K.; Ma, L.; Li, R. Green Chem. 2019, 21,2448.
[20]	He, H.W.; Li, Z.; Li, K.; Lei, G.Y.; Guan, X.L.; Zhang, G.L.; Zhang, F.B.; Fang, X.B.; Peng, W.C.; Li, Y. ACS Appl. Mater. Interfaces 2019, 11,31844.
[21]	Yang, L.J.; Jiang, S.J.; Zhao, Y.; Zhu, L.; Chen, S.; Wang, X.Z.; Wu, Q.; Ma, J.; Ma, Y.W.; Hu, Z. Angew. Chem. Int. Ed. 2011, 50,7132.
[22]	Zhao, Y.; Yang, L.J.; Chen, S.; Wang, X.Z.; Ma, Y.W.; Wu, Q.; Jiang, Y.F.; Qian, W.J.; Hu, Z. J. Am. Chem. Soc. 2013, 135,1201.
[23]	Jiang, Y.F.; Yang, L.J.; Sun, T.; Zhao, J.; Lyu, Z.Y.; Zhuo, O.; Wang, X.Z.; Wu, Q.; Ma, J.; Hu, Z. ACS Catal. 2015, 5,6707.
[24]	Zhong, G.Y.; Wang, H.J.; Yu, H.; Peng, F. Acta Chim. Sinica 2017, 75,943. (in Chinese)
	( 钟国玉, 王红娟, 余皓, 彭峰, 化学学报, 2017, 75,943.)
[25]	Li, W.; Wang, D.; Zhang, Y.; Tao, L.; Wang, T.; Zou, Y.; Wang, Y.; Chen, R.; Wang, S. Adv. Mater. 2020, 32,1907879.
[26]	Wu, Q.; Yang, L.J; Wang, X.Z.; Hu, Z. Acc. Chem. Res. 2017, 50,435.
[27]	Zhang, Z.Q.; Ge, C.X.; Chen, Y.G.; Wu, Q.; Yang, L.J.; Wang, X.Z.; Hu, Z. Acta Chim. Sinica 2019, 77,60. (in Chinese)
	( 张志琦, 葛承宣, 陈玉刚, 吴强, 杨立军, 王喜章, 胡征, 化学学报, 2019, 77,60.)
[28]	Wu, Q.; Yang, L.J; Wang, X.Z.; Hu, Z. Adv. Mater. 2020, 32,1904177.
[29]	Wu, Q.; Yang, L.J.; Wang, X.Z.; Hu, Z. Sci. China Chem. 2020, 63,665.
[30]	Tang, G.A.; Mao, K.; Zhang, J.; Lyu, P.; Cheng, X.Y.; Wu, Q.; Yang, L.J.; Wang, X.Z.; Hu, Z. Acta Chim. Sinica 2020, 78,444. (in Chinese)
	( 汤功奥, 毛鲲, 张静, 吕品, 程雪怡, 吴强, 杨立军, 王喜章, 胡征, 化学学报, 2020, 78,444.)
[31]	Zhang, J.; Tang, G.A.; Zeng, Y.; Wang, B.X.; Liu, L.W.; Wu, Q.; Yang, L.J.; Wang, X.Z.; Hu, Z. Acta Chim. Sinica 2020, 78,572. (in Chinese)
	( 张静, 汤功奥, 曾誉, 王保兴, 刘力玮, 吴强, 杨立军, 王喜章, 胡征, 化学学报, 2020, 78,572.)
[32]	Ferrari, A.C.; Robertson, J. Phys. Rev. B 2000, 61,14095.
[33]	Dresselhaus, M.S.; Jorio, A.; Hofmann, M.; Dresselhaus, G.; Saito, R. Nano Lett. 2010, 10,751.
[34]	Ferrari, A.C.; Basko, D.M. Nat. Nanotechnol. 2013, 8,235.
[35]	Bourrat, X.; Langlais, F.; Chollon, G.; Vignoles, G.L. J. Braz. Chem. Soc. 2006, 17,1090.
[36]	Maslova, O.A.; Ammar, M.R.; Guimbretière, G.; Rouzaud, J.N.; Simon, P. Phys. Rev. B 2012, 86,134205.
[37]	Xie, K.; Qin, X.T.; Wang, X.Z.; Wang, Y.N.; Tao, H.S.; Wu, Q.; Yang, L.J.; Hu, Z. Adv. Mater. 2012, 24,347.
[38]	Bu, Y.F.; Sun, T.; Cai, Y.J.; Du, L.Y.; Zhuo, O.; Yang, L.J.; Wu, Q.; Wang, X.Z.; Hu, Z. Adv. Mater. 2017, 29,1700470.
[39]	Grimme, S. Angew. Chem. Int. Ed. 2008, 47,3430.