Supplementary Material
Layered double alkoxides, a novel group of layered double hydroxides without water content
Gábor Vargaa,b, Márton Szabadosa,b, Ákos Kukoveczc, Zoltán Kónyac,d, Tamás Vargac, Pál Siposb,e, István Pálinkóa,b*
aDepartment of Organic Chemistry, University of Szeged, Dóm tér 8, Szeged, H-6720 Hungary.
bMaterials and Solution Structure Research Group and Interdisciplinary Excellence Centre, Institute of Chemistry, University of Szeged, Aradi Vértanúk tere 1, Szeged, H- 6720 Hungary.
cDepartment of Applied and Environmental Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged, H-6720 Hungary.
dMTA-SZTE Reaction Kinetics and Surface Chemistry Research Group, University of Szeged, Rerrich Béla tér 1, Szeged, H-6720 Hungary.
eDepartment of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, Szeged, H-6720 Hungary.
*The e-mail address of the corresponding author: palinko@chem.u-szeged.hu (István Pálinkó)
5 10 15 20 25 30 35 40
Intensity (cps)
2 (o) A
B
001 002
001
002
SFigure 1. XRD pattern of the water-free CaAl-LDH after solvolysis-co-precipitation of Ca(II) and Al(III) ethoxides using propanol for solvolysis (A) at 30°C and (B) at 60°C. XRD patterns were indexed on the basis of JCPDS#89-6723.
S2 SFigure 2. SEM image of water-free CaAl–LDH (CaAl–LDA) using propanol for solvolysis- co-precipitation at 60oC.
0 1 2 3 4 5
0 10000 20000
0 1 2
0 5000 10000 15000 20000 25000 30000
Intensity (cps)
Energy (keV)
Ca k
O k Al k Ca
Energy (keV) Al k O k Mg k
Na k
Intensity (cps)
A B
SFigure 3. EDX spectra of (A) CaAl-LDA and (B) MgAl-LDA.
S3 SFigure 4. Elemental maps for CaAl-LDA [(A) and (B)] and MgAl-LDA (C), (D) and (E).
STable 1. Layer thickness, d-spacings and cell parameters for LDAs, nitrate-containing LDHs and alkoxide intercalated LDH
Composite d-space (Å) thickness (Å) a parameter (Å) c parameter (Å)
MgAl-LDA 7.88 4.5 3.02 24.16
Mg2Al–NO3–
-LDH 8.58 4.82 3.08 22.91
CaAl–LDA 7.49 — 5.92 15.01
Ca2Al–NO3–-LDH 8.26 2.43 5.45 17.16
C2H5O−–MgAl-LDH 8.181 4.82 3.071 23.981
Calculation: MgAl-LDH/LDA: a = 2d(110), c = (3d(003) +6d(006) +9d(009))/3; CaAl-LDH/LDA:
a = 2d(110), c = 2d(002)
S4
100 200 300 400 500 600 700 800
40 50 60 70 80 90 100
Temperature (°C)
Weight (%)
120
346
733
-2,0 -1,5 -1,0 -0,5 0,0
Deriv, Weight (%/°C)
(a)
100 200 300 400 500 600 700
65 70 75 80 85 90 95 100
Weight (%)
Temperature (°C) 106
242 415
600 (b)
-0,15 -0,10 -0,05 0,00 0,05 0,10
Deriv. Weight (%/o C)
SFigure 5. TG/DTG curves for the (a) MgAl-LDH sample prepared by solvolysis-precipitation from Mg(II)Al(III) ethoxide at 60°C and (b) MgAl–NO3––LDH.
S5
100 200 300 400 500 600 700 800
40 50 60 70 80 90 100
Temperature (°C)
Weight (%)
103
461 (a)
-2,0 -1,5 -1,0 -0,5 0,0
Deriv, Weight (%/°C)
200 400 600 800
60 80 100
-0,30 -0,25 -0,20 -0,15 -0,10 -0,05 0,00
Weight (%)
Temperature (oC) (b)
660 250
56
430
Deriv. Weight (%/o C)
SFigure 6. TG/DTG curves of (a) water-free CaAl–LDA and (b) CaAl–NO3––LDH.
S6
4000 3500 3000 1500 1000
Intensity (a.u.)
Wavenumber (cm–1) 2941
2873 2800
1461 1393 1085
1165
A B
1409 1345
782 3661
3411
SFigure 7. IR spectra of (A) CaAl–NO3––LDH and (B) water-free CaAl–LDH (CaAl–LDA).
4000 3500 3000 1500 1000
Absorbance (a.u.)
Wavenumber (cm-1) 1405
1068 1590
1468
873
830 615 1361
2834 2750 3592
SFigure 8. IR spectra of MgAl–LDA (prepared by solvolysis-co-precipitation of Mg(II) and Al(III)ethoxides at 60°C) after 9-month-long storage in air.
S7 Optimisation procedure of the catalytic test reaction
0,0 0,1 0,2 0,3 0,4 0,5
0 20 40 60 80 100
Yield (%)
Catalyst loading (g)
MgAl–LDA CaAl–LDA MgAl–LDH
SFigure 9. Effect of the catalyst loading for the Knoevenagel condensation between benzaldehyde (10.0 mmol) and malononitrile (15.0 mmol); under reflux (~75°C), t = 180 min, v(EtOH) = 3.0 cm3.
STable 2. Effect of the solvent for the Knoevenagel condensation between benzaldehyde (10.0 mmol) and malononitrile (15.0 mmol); T = 125°C/reflux, t = 180 min, v(solvent) = 3.0 cm3, mcat = 0.2 g.
Solvent Yield (%)a Yield (%)b
chloroform 1 10
acetonitrile – –
ethanol 100 100
solvent-free 100 100
a: yield for water-free CaAl–LDH (CaAl–LDA), b: yield for water-free MgAl–LDH (MgAl–
LDA).
S8
MgAl–LDA CaAl–LDA
0 20 40 60 80 100
Yield (%)
25 °C 35 °C 50 °C 75 °C 100 °C 125 °C
SFigure 10. Effect of the reaction temperature for the Knoevenagel condensation between benzaldehyde (10.0 mmol) and malononitrile (15.0 mmol); t = 180 min, solvent-free, mcat= 0.2 g.
CHO +
CN
CN NC CN
OH
NC CN base
-H2O
SScheme 1 The reaction sequence between benzaldehyde and malononitrile.
References
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2016:119:273–289.
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Intracrystalline structure and release pattern of ferulic acid intercalated into layered double hydroxide through various synthesis routes. Appl Calay Sci. 2015:112–113:32–39.
[3] Sacerdoti M, Passaglia E, Hydrocalumite from Latium, Italy: its crystal structure and relationship with related synthetic phases. in Neues Jahrbuch für Mineralogie, Monatshefte 1988:462−475.
