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Supporting Information
Johannes Steinbauer,a Lars Longwitz,a Marcus Frank,b Jan Dirk
Epping,c Udo Kragl,d Thomas Wernera*
aLeibniz‐Institute of Catalysis e.V. at the University of Rostock,
Albert‐Einstein‐Straße 29a, 18059 Rostock, Germany.
b Medical Biology and Electron Microscopy Centre, University Medicine
Rostock, Strempelstraße 14, 18057 Rostock, Germany.
cBerlin University of Technology, Institute of Chemistry,
Straße des 17. Juni 135, 10623 Berlin, Germany.
dInstitute of Chemistry, Technische Chemie, University of Rostock, Germany
1. General Considerations 1
2. Proposed mechanism of the reaction and halogen exchange 3
3. Solid‐state NMR‐spectra and IR‐spectra of the synthesized catalysts 6
4. SEM pictures, EDX, DSC and TGA‐MS 37
5. NMR‐spectra of the synthesized carbonates 50
6. References 62
Electronic Supplementary Material (ESI) for Green Chemistry.This journal is © The Royal Society of Chemistry 2017
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1. General Considerations
All chemicals were purchased from commercial sources in purities of ≥95% and used without
further purification. The triphenyl phosphane functionalized polystyrene support (1.4–2.0
mmol.g–1 P‐loading) was purchased from Fluorochem Ltd. The 4‐bromo methyl functionalized
polystyrene support (2.96 mmol.g–1 Br‐loading) was purchased from Carbosynth Limited.
The bromo propyl functionalized support (1.5 mmol . g‐1 Br‐loading) was purchased from
Sigma‐Aldrich Chemie GmbH. Deuterated solvents were ordered from Deutero GmbH and
stored over molecular sieves (3 Å). NMR spectra were received using Bruker 300 Fourier,
Bruker AV 300 and Bruker AV 400 spectrometers. Chemical shifts are reported in ppm
relative to the deuterated solvent. Coupling constants are expressed in Hertz (Hz). The
following abbreviations are used: s= singlet, d= doublet, t= triplet and m= multiplet. NMR
yields were determined by using mesitylene as internal standard. Elementary analysis was
performed on a TruSpec CHMS Micro from Leco. IR spectra were recorded on a Nicolet iS10
MIR FT‐IR‐spectrometer from Thermo Fisher Scientific. Thin layer chromatography was
performed on Merck TLC‐plates with fluorescence indication (silica type 60, F254), spots were
visualized using UV‐light or potassium permanganate. Flash chromatography was performed
using silica with a grain size of 40–63 µm from Macherey‐Nagel.
Solid state NMR spectra were recorded with a Bruker Avance 400 MHz spectrometer
operating at 100.56 MHz for 13C, 161.87 MHz for 31P and 399.88 MHz for 1H. All experiments
were carried out at a MAS rate of 10 kHz using a 4 mm MAS HX double resonance probe. The
1H and 31P π/2 pulse lengths were 3.1 µs and 2.0 µs, respectively. T wo pulse phase
modulation (TPPM) heteronuclear dipolar decoupling was used during acquisition. 1H‐13C
cross polarization magic angle spinning (CP‐MAS) NMR experiments were measured using
contact time of 2.0 ms for 13C and recycle delays of 2 s. All 13C spectra are referenced to
external TMS at 0 ppm using adamantane as a secondary reference. All 31P spectra were
measured with recycle delays of 20 s and referenced to a 85% solution of phosphoric acid in
water at 0 ppm using ammonium dihydrogen phosphate as a secondary reference.
The SEM and EDX measurements were performed at a working distance of 9.6 mm at 10.0
keV with a Merlin VP Compact field emission scanning electron microscope (Carl Zeiss),
respectively. The microscope is equipped with an Inlens Duo‐Detector and a HE‐SE Detector
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(high efficiency Everhard Thornley detector) for morphological analysis and a Bruker XFlash
6/30 energy dispersive x‐ray‐spectrometer (EDX spectrometer) for elemental analysis.
Sample Preparation: The sample was disposed without any pretreatment on an aluminium
stub (12.5 mm diameter, G301F, Plano GmbH) with adhesive carbon tape (3347, Plano
GmbH). After carbon coating (EM SCD 500, Leica Microsystems) the sample was transferred
to the microscope. After morphological examination elemental mapping was performed on
selected grains with surfaces uniformly exposed into the direction of the detector for 10
minutes, in addition an elemental spectrum with 2x106 counts was recorded on the grain
surface area.
SEM images shown in the manuscript (Figures 2 and 3) are depicted in later section of the
supporting information with a scale (SI34–36). The color intensity ranges used in the EDX
mappings are 0–100 for silicon and 0–20 for bromine or phosphorus. Images with a color
scale are shown in chapter 4 of the supporting information (SI37 and SI38). For the
quantification of intensity, the following maxima were used: Bromine (Lα1 and Lβ1) at 1.496
keV, silicon (Kα1) at 1.740 keV, phosphorus (Kα1) at 2.010 keV. Full overview spectra
corresponding to the depicted mappings in the manuscript are shown in chapter 4 of the ESI
(SI42–46).
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2. Proposed mechanism of the reaction (SI1)
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Proposed mechanism for the halogen exchange occuring in run 13 (SI2)
The proposed halogen exchange mechanism is shown in SI2. When the epoxide ring is
opened by the bromide anion, both the chloride and bromide are able to act as a leaving
group, when the cyclic carbonate forms by an intramolecular nucleophilic substitution.
Normally, bromide is the superior leaving group, but as a side reaction the chloride will
react, which leads to the formation of phosphonium chloride and the bromo functionalized
cyclic carbonate. Due to the small concentration of bromide still left in the catalyst before
the reaction and the similarity to the chlorine derivate, the bromo functionalized product
was not detected by GCMS or NMR spectroscopy. In general, chlorides of bifunctional
catalysts are not as active as bromides or iodides due to their poor leaving group ability and
their strong interaction with the hydrogen bond donor and thus the activity of the catalyst
after the reaction with epichlorohydrin 1l is a lot lower.
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3. SS NMR‐spectra, IR‐spectra, DSC and TGA‐MS of the synthesized catalysts
13C SS NMR Triphenyl phosphane on polymer (4b) SI3
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31P SS NMR Triphenyl phosphane on polymer (4b) SI4
PPh
Ph
PS
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IR spectrum Triphenyl phosphane on polymer (4b) SI5
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13C SS NMR Polystyrene supported catalyst (6a) SI6
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31P SS NMR Polystyrene supported catalyst (6a) SI7
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IR spectrum Polystyrene supported catalyst (6a) SI8
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13C SS NMR Polystyrene supported catalyst (6b) SI9
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31P SS NMR Polystyrene supported catalyst (6b) SI10
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IR spectrum Polystyrene supported catalyst (6b) SI11
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13C SS NMR Polystyrene supported catalyst (6c) SI12
PS
PPh
Ph
Br
OH
OH
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31P SS NMR Polystyrene supported catalyst (6c) SI13
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IR spectrum Polystyrene supported catalyst (6c) SI14
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13C SS NMR Polystyrene supported catalyst (6d) SI15
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31P SS NMR Polystyrene supported catalyst (6d) SI16
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IR spectrum Polystyrene supported catalyst (6d) SI17
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13C SS NMR Polystyrene support (9b) SI18
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IR spectrum Polystyrene support (9b) SI19
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13C SS NMR Polystyrene supported catalyst (13) SI20
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31P SS NMR Polystyrene supported catalyst (13) SI21
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IR spectrum Polystyrene supported catalyst (13) SI22
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13C SS NMR silica support (9a) SI23
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IR spectrum silica support (9a) SI24
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13C SS NMR silica supported catalyst (12) SI25
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31P SS NMR silica supported catalyst (12) SI26
Si
PPhPh OH
Br
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Comparison of 31P NMR of homogeneous catalyst 10 (top), heterogeneous catalyst 12 (middle) and precursor phosphane 7 (bottom) SI27
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IR spectrum silica supported catalyst (12) SI28
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13C SS NMR silica supported catalyst after 15 Cycles (12) SI29
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31P SS NMR silica supported catalyst after 15 Cycles (12) SI30
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IR spectrum silica supported catalyst after 15 Cycles (12) SI31
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Comparison of 13C SS NMR of fresh 12 (bottom) and 12 after 15 Cycles (top) SI32
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Comparison of 31P SS NMR of fresh 12 (bottom) and 12 after 15 Cycles (top) SI33
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4. DSC, TGA‐MS, SEM pictures and EDX mapping
SEM (Figure 2, Ia) silica support 9a with scale SI34
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SEM (Figure 2, IIa) catalyst 12 with scale SI35
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SEM (Figure 3, IIa) catalyst 12 after 15 cycles with scale SI36
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EDX Mapping with color coded intensity range of silicon of catalyst 12 (Figure 2, Ib) with color scale SI37
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EDX Mapping with color coded intensity range of silicon of catalyst 12 (Figure 3, Ib) with color scale SI38
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SEM Pictures and EDX Mapping of Silicon and Bromine for fresh catalyst, after 8 cycles and after 15 cycles. SI39
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SEM Picture at 20 µm scale of fresh catalyst 12 (left) and after 15 cycles (right) SI40
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Comparison of EDX spectra of catalyst 12 after 8 and 15 cycles between 2.25 and 3 keV (chlorine Kat 2.621 keV) SI41
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Comparison of EDX spectra of fresh catalyst 12, after 8 cycles and after 15 cycles SI42
0
5
10
15
20
25
30
35
40
0,00 0,50 1,00 1,50 2,00 2,50 3,00
CPS
/ eV
Energy/ keV
12 fresh12 after 8 Cycles12 after 15 Cycles
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Overview EDX spectra of Support 9a SI43
0
5
10
15
20
25
30
35
40
0,00 0,50 1,00 1,50 2,00 2,50 3,00
CPS
/ eV
Energy / keV
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Overview EDX spectra of fresh catalyst 12 SI44
0
5
10
15
20
25
30
35
40
0,00 0,50 1,00 1,50 2,00 2,50 3,00
CPS
/ eV
Energy/ keV
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Overview EDX spectra of catalyst 12 after 8 cycles SI45
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Overview EDX spectra of catalyst 12 after 15 cycles SI46
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DSC/TGA‐MS of the silica supported catalyst 12 SI47
In the spectra of the DSC/TGA‐MS we observed a starting decomposition of the catalyst at around 200 °C. At around 300 °C an exothermic
degradation reaction occurs which leads to an increased heatflow with a peak at 357 °C, which was observed in the DSC. During the heating from
300 °C to 400 °C the mass of the catalyst dropped about 10%. In the temperature range of 400 °C to around 500 °C the decrease of the mass
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slowed down. At temperatures above 500 °C to up to 555 °C another exothermic degradation reaction occurred, which was monitored by an
increased heatflow and furthermore, a mass decrease of about 8% was observed. Since the silica support is not supposed to decompose, and the
mass content of the phosphonium salt in the catalyst material is around 23%, the observed mass loss of around 23% during the measurement fits
nicely.
MS traces SI48
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Possible decomposition species
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5. NMR‐spectra of the synthesized carbonates
4‐Ethyl‐1,3‐dioxolan‐2‐one (2b) SI49 [1]
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4‐(tert‐Butoxymethyl)‐1,3‐dioxolan‐2‐one (2c) SI50 [1]
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4‐Butyl‐1,3‐dioxolan‐2‐one (2d) SI51 [1]
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4‐Phenyl‐1,3‐dioxolan‐2‐one (2e) SI52 [1]
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4‐Hexyl‐1,3‐dioxolan‐2‐one (2f) SI53 [1]
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Methyl 9‐(2‐Oxo‐1,3‐dioxolan‐4‐yl)nonanoate (2g) SI54 [1]
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4‐(But‐3‐en‐1‐yl)‐1,3‐dioxolan‐2‐one (2h) SI55 [1]
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4‐[(Allyloxy)methyl]‐1,3‐dioxolan‐2‐one (2i) SI56 [1]
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4‐(Chloromethyl)‐4‐methyl‐1,3‐dioxolan‐2‐one (2j) SI57 [2]
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4‐Methyl‐1,3‐dioxolan‐2‐one (2k) SI58 [1]
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4‐(Chloromethyl)‐1,3‐dioxolan‐2‐one (2l) SI59 [1]
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4‐(iso‐Propoxymethyl)‐1,3‐dioxolan‐2‐one (2m) SI60 [1]
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6. References
[1] H. Büttner, J. Steinbauer, T. Werner, ChemSusChem 2015, 8, 2655–2669. [2] J. Steinbauer, A. Spannenberg, T. Werner, Green Chem. 2017, 10.1039/C7GC01114H.
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