Green Chemistry
Paper
(WHSV = 2.4 gsubstrate gcat h−1 and T = 350 °C). Since the Industrie, FCI) for the generous support of his PhD project.
main by-product is 3-methyl-2-pyrrolidone, a reduction in resi- Lastly, Saint-Gobain NorPro is acknowledged for providing the
dence time through an increase in substrate flow rate (WHSV = catalyst support materials mentioned above.
−1
−1
3.6 gsubstrate gcat h−1) increases yields to 90 mol% of vinyl-
pyrrolidone. Overall, the setup was operated continuously for
−1
7 h converting 20 gsubstrate gcatalyst
(see Fig. S10†). The
Notes and references
collected product mixture was vacuum distilled leading to the
facile separation of 3-methyl-N-vinyl-2-pyrrolidone (≥95%
NMR, see Fig. S8†), which may be used for polymer synthesis.
It thus appears that an industrial process could make use of
rather simple and efficient separation techniques.
1 (a) T. Werpy, G. Petersen, A. Aden, J. Bozell, J. Holladay,
J. White and A. Manheim, Top Value Added Chemicals from
Biomass (Volume I), U.S.: Department of Energy, 2004;
(b) J. Holladay, J. Bozell, J. White and D. Johnson, Top
Value Added Chemicals from Biomass (Volume II), U.S:
Department of Energy, 2007.
Conclusions
2 R. Palkovits, Chem. Ing. Tech., 2018, 90, 1699–1708.
3 J. Pritchard, G. A. Filonenko, R. van Putten, E. J. M. Hensen
and E. A. Pidko, Chem. Soc. Rev., 2015, 44, 3808–3833.
4 (a) X. Di, C. Li, G. Lafaye, C. Especel, F. Epron and C. Liang,
Catal. Sci. Technol., 2017, 7, 5212–5223; (b) X. Di, C. Li,
B. Zhang, J. Qi, W. Li, D. Su and C. Liang, Ind. Eng. Chem.
Res., 2017, 56, 4672–4683.
5 K. H. Kang, U. G. Hong, Y. Bang, J. H. Choi, J. K. Kim,
J. K. Lee, S. J. Han and I. K. Song, Appl. Catal., A, 2015, 490,
153–162.
6 T. Toyao, S. M. A. Hakim Siddiki, A. S. Touchy, W. Onodera,
K. Kon, Y. Morita, T. Kamachi, K. Yoshizawa and
K. Shimizu, Chem. – Eur. J., 2017, 23, 1001–1006.
7 L. Corbel-Demailly, B.-K. Ly, D.-P. Minh, B. Tapin,
C. Especel, F. Epron, A. Cabiac, E. Guillon, M. Besson and
C. Pinel, ChemSusChem, 2013, 6, 2388–2395.
8 C. S. Spanjers, D. K. Schneiderman, J. Z. Wang, J. Wang,
M. A. Hillmyer, K. Zhang and P. J. Dauenhauer,
ChemCatChem, 2016, 8, 3031–3035.
9 J. Ullrich and B. Breit, ACS Catal., 2018, 8, 785–789.
10 A. S. Touchy, S. M. A. Hakim Siddiki, K. Kon and
K. Shimizu, ACS Catal., 2014, 4, 3045–3050.
11 X.-L. Du, L. He, S. Zhao, Y.-M. Liu, Y. Cao, H.-Y. He and
K.-N. Fan, Angew. Chem., Int. Ed., 2011, 50, 7815–7819.
12 (a) J. D. Vidal, M. J. Climent, P. Concepción, A. Corma,
S. Iborra and M. J. Sabater, ACS Catal., 2015, 5, 5812–5821;
(b) J. D. Vidal, M. J. Climent, A. Corma, P. Concepción and
S. Iborra, ChemSusChem, 2017, 10, 119–128.
The reaction network for the reductive amidation of dicar-
boxylic acids with ethanolamine has been elucidated, clearly
showing the rate-determining nature of the hydrogenation
step. Based thereon, the challenge of this transformation lies
in (i) the low reducibility of the intermediate imide functional-
ity and (ii) the possibility for over-reduction, e.g. of the
hydroxyl-substituent introduced with ethanolamine. Ru/C
stands out from the set of common reduction catalysts tested
herein, due to its ability to activate not only H2, but also CvO
bonds. It could be shown that, using optimal process con-
ditions, the reductive amidation of succinic and itaconic acid
can yield up to 75 mol% of valuable products. In order to con-
clude the sustainable value chain leading from biogenic acids
to monomers, N-(2-hydroxyethyl)-2-pyrrolidones were de-
hydrated in a continuous gas phase reactor leading to NVP
monomers. With water as the only by-product and the use of
solid catalysts, this process shows promise to overcome the
drawbacks of fossil-based NVP production. The achievable
yield of NVP from succinic acid over the whole two-step
process is above 72 mol% and could be further optimized by
the design of improved chemoselective catalysts for reductive
amidation. As a potential for future research, it is noted that
the applied Ru/C catalyst requires long reaction times to
achieve high conversion and product yield. It would thus be
interesting to develop alternative materials with a more pro-
nounced ability to activate CvO bonds. Investigations in this
direction are ongoing.
13 G. Gao, P. Sun, Y. Li, F. Wang, Z. Zhao, Y. Qin and F. Li,
ACS Catal., 2017, 7, 4927–4935.
14 A. M. Smith and R. Whyman, Chem. Rev., 2014, 114, 5477–
5510.
Conflicts of interest
15 G. Budroni and A. Corma, J. Catal., 2008, 257, 403–408.
16 J. F. White, J. E. Holladay, A. A. Zacher, J. G. Frye and
T. A. Werpy, Top. Catal., 2014, 57, 1325–1334.
There are no conflicts to declare.
17 Y. Louven, K. Schute and R. Palkovits, ChemCatChem, 2019,
11, 439–442.
Acknowledgements
We thank the German Federal Ministry of Education and 18 (a) W. Reppe, Experientia, 1949, 5, 93–132; (b) W. Reppe,
Research (BMBF) for funding of the projects BioPyrr and
BioPVP (FKZ IBÖ-03 031B0249 and 031B0487 A) in the frame-
work of “New Products for the Bioeconomy” (Neue Produkte
für die Bioökonomie). Furthermore, Mr Haus likes to thank
the German Chemical Industry Fund (Fonds der chemischen
et al., Liebigs Ann. Chem., 1956, 601, 81–137;
(c) A. L. Harreus, R. Backes, J.-O. Eichler, R. Feuerhake,
C. Jäkel, U. Mahn, R. Pinkos and R. Vogelsang,
2-Pyrrolidone, in Ullmann’s Encyclopedia of Industrial
Chemistry, 2011.
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Green Chem., 2019, 21, 6268–6276 | 6275