Catalysis Science & Technology
Paper
extraction with 2,2,4-trimethylpentane. Hence, despite the
lower activity, we developed a suitable iridium system with
higher selectivities and much lower catalyst leaching, which
is competitive to experiments using a rhodium catalyst.
2 C. D. Frohning, C. W. Kohlpaintner and H.-W. Bohnen,
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R. Franke, D. Selent and A. Börner, Chem. Rev., 2012, 112,
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Conclusions
4
A. Behr and P. Neubert, Applied homogeneous catalysis,
In summary, selective recycling systems for the iridium-
catalysed hydroformylation of 1-octene based on dimethyl-
formamide (DMF) and propylene carbonate (PC) as polar sol-
vents were investigated for the first time. High yields and
chemoselectivities towards the desired oxo-products at rates
of approximately 91% were observed. The results demon-
strated good activity for the catalyst complex formed by
the precursor IrIJcod)IJacac) and the monosulfonated
triphenylphosphine ligand (TPPMS) at conversion rates up to
Wiley-VCH, Weinheim, 2012.
5 G. D. Frey, J. Org. Chem., 2014, 754, 5–7.
6 J. Matthey, Platinum 2013, Johnson Matthey Public Limited
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7 F. P. Pruchnik, Organometallic chemistry of the transition
elements, Springer-Verlag, 1990.
8 I. Piras, R. Jennerjahn, R. Jackstell, A. Spannenberg, R.
Franke and M. Beller, Angew. Chem., Int. Ed., 2011, 50,
280–284.
9
0% after a reaction time of 6 h. The catalyst complex and
9 J. Pospech, I. Fleischer, R. Franke, S. Buchholz and M.
Beller, Angew. Chem., 2013, 125, 2922–2944.
10 C. De, R. Saha, S. K. Ghosh, A. Ghosh, K. Mukherjee, S. S.
Bhattacharyya and B. Saha, Res. Chem. Intermed., 2013, 39,
3463–3474.
oxo-products were separated selectively and effectively using
the TPPMS ligand at iridium leaching rates of only 0.2%. The
combination of this catalyst system with the appropriate
polar solvent PC or DMF and a non-polar solvent such as
2
,2,4-trimethylpentane allowed for different recycling systems:
a thermomorphic solvent system and a homogeneous reac-
tion followed by ex situ extraction. Ultimately, a DMF–H
11 C. W. Kohlpaintner, R. W. Fischer and B. Cornils, Appl.
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12 G. Frey and G. Dämbkes, 75 Jahre Oxo-Synthese, Klartext,
Essen, 2013.
13 B. Cornils and W. A. Herrmann, Aqueous-Phase
Organometallic Catalysis, Wiley-VCH, Weinheim, 2004.
14 A. Behr, B. Turkowski, R. Roll, R. Schöbel and G. Henze,
Multiphase Catalysis in Temperature-Dependent Multi-Com-
ponent Solvent (TMS) Systems, in Regulated Systems for
Multiphase Catalysis, ed. W. Leitner and M. Hölscher,
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15 E. Schäfer, Y. Brunsch, G. Sadowski and A. Behr, Ind. Eng.
Chem. Res., 2012, 51, 10296–10306.
2
O
system with a downstream extraction allowed for both a
highly selective hydroformylation of 1-octene and an efficient
separation of catalyst from the products. The stability and
activity of the iridium catalyst was confirmed over the course
of 5 recycle runs. Because of higher chemoselectivities and
lower catalyst leaching the iridium system seems to be very
competitive to rhodium-catalysed hydroformylation, which
was performed during our investigations, too. Additionally,
the results obtained with this recycling concept enable a fur-
ther investigation of this reaction in a continuously operated
miniplant. The results of those subsequent experiments will
soon be published in a separate paper.
16 K. Kunna, C. Müller, J. Loos and D. Vogt, Angew. Chem., Int.
Ed., 2006, 45, 7289–7292.
1
7 M. Jakuttis, A. Schönweiz, S. Werner, R. Franke, K.-D. Wiese,
M. Haumann and P. Wasserscheid, Angew. Chem., Int. Ed.,
Acknowledgements
2
011, 50, 4492–4495.
The described experiments were part of the PROFORMING
project (no. 03X3559). The authors would like to thank BMBF
18 M. Kraume, Chem. Ing. Tech., 2013, 85, 1–13.
19 R. Schomäcker, M. Schwarze, H. Nowothnick, A. Rost and T.
Hamerla, Chem. Ing. Tech., 2011, 83, 1343–1355.
(German Federal Ministry of Education and Research), Evonik
Industries, LIKAT (Leibniz Institute for Catalysis) and
SUPREN (Sustainable Process Engineering) for their coopera-
tion and helpful input. The authors also thank Umicore AG &
Co. KG for donation of transition metal compounds.
20 M. Müller, Y. Kasaka, D. Müller, R. Schomäcker and G.
Wozny, Ind. Eng. Chem. Res., 2013, 52, 7259–7264.
21 S. L. Desset, U. Hintermair, Z. Gong, C. C. Santini and D. J.
Cole-Hamilton, Top. Catal., 2010, 53, 963–968.
2
2 G. Kiedorf, D. M. Hoang, A. Müller, A. Jörke, J. Markert, H.
Arellano-Garcia, A. Seidel-Morgenstern and C. Hamel, Chem.
Eng. Sci., 2014, 115, 31–48.
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