Supporting Information
Synthesis and evaluation of new diglycolamides for the
Americium/Curium separation by liquid-liquid extraction
S. Chapron, 1,2 C. Marie, 1 G. Arrachart, 2 M. Miguirditchian, 1 S. Pellet-Rostaing
1
2
CEA, Nuclear Energy Division, RadioChemistry & Processes Department,
SMCS/LEPS, BP 17171 F-30207 Bagnols-sur-Cèze cedex, France
2
Institut de Chimie Séparative de Marcoule, CNRS/CEA/UM2/ENSCM, UMR 5257,
LTSM, Bât 426, F-30207 Bagnols-sur- Cèze, France
E-mail: cecile.marie@cea.fr
Synthesis of ligands
Reactants and solvents (analytically pure) were supplied by Aldrich, Alfa Aesar and
Carlo Erba and were used without further purification. Moisture sensitive reactions were carried
out under an argon atmosphere with dried solvents (AcroSeal®).
NMR spectra were recorded on a Bruker 400 ultrashield VS (1H: 400 MHz
13
C: 100
MHz) instrument using deuterated chloroform as solvent. The chemical shifts (δ ppm) are
reported using the solvent (CDCl3: 7.26 ppm 1H; 77.16 ppm 13C) as an internal reference and
coupling constants (Hz) are reported in the standard fashion. High-resolution mass spectra
(HRMS) were recorded on a GCT Waters (EI + CI) TOF analyzer.
Analytical thin-layer chromatography was carried out on silica gel Merck 60 F254 (0.25
mm) using several revealing agents (UV: 254nm, ninhydrin (1% in ethanol), phosphomolybdic
acid (50g.L-1 in ethanol) or I2 vapors). Flash chromatography separation was performed on an
Agilent Intelliflash 971-FP instrument.
General procedure for the preparation of diglycolamides:
2.5eq of oxalyl chloride was added to 1eq of diglycolic acid in DCM at room
temperature. Then some drops of DMF were added as catalyst and the mixture was stirred until
the complete solubilization of solids (average 1h). The solvent and excess of oxalyl chloride
were removed under reduced pressure to give diglycolic chloride which was engaged in the
next step without further purifications.
A mixture of 2.5eq of triethylamine and 2.5eq of the desired secondary amine was stirred
for 1h in DCM at room temperature. Then diglycolic chloride diluted in DCM was added
dropwise to the mixture. The reaction was stirred for 1h at room temperature. The mixture was
filtered of to remove precipitates (triethylammonium chloride) and then the organic phase was
washed by a 1M hydrochloric acid solution and brine. The organic phase was then dried over
anhydrous sodium sulfate, filtered and concentrated under reduce pressure. The residue was
dissolved in ethyl acetate and filtered on silica gel. Solvent was removed under reduce pressure
to give the desired product.
Tetra-n-Propyl DiglycolAmide (TnPDGA): The title compound was
prepared from diglycolic acid (1.342g, 10.00mmol) and dipropyl amine
(3.5mL, 2.58g, 25.5mmol) following the general procedure to give a
yellow oil (1.376g, 4.58mmol, 46% yield); 1H NMR (400MHz, CDCl3) δ 4.18 (4H, s,
OCH2CO), 3.09 (8H, dt, NCH2, J=40.8, 7.6Hz), 1.43 (8H, m, CH2CH2CH3), 0.75 (12H, m,
CH3);
13
C NMR (100MHz, CDCl3) δ 168.5 (C=O), 69.0 (OCH2CO), 48.4 (NCH2), 47.3
(NCH2), 22.0 (CH2CH2CH3), 20.7 (CH2CH2CH3), 11.3 (CH3), 11.1 (CH3); HRMS (clcd
301.2486) 301.2668
Tetra-iso-Propyl DiglycolAmide (TiPDGA): The title compound was
prepared from diglycolic acid (1.341g, 10.00mmol) and di-iso-propyl
amine (3.5mL, 2.53g, 25.5mmol) following the general procedure. The residue was purified by
flash chromatography (cyclohexane/ethyl acetate 70/30 to 50/50) to give the product as a white
solid (1.03g, 3.37mmol, 34% yield); 1H NMR (400MHz, CDCl3) δ 4.16 (4H, s, OCH2CO), 3.62
(4H, dm, N(CH(CH3)2)2, J=188.2Hz), 1.23 (24H, dd, CH3, J=88.2, 6.8Hz); 13C NMR (100MHz,
CDCl3) δ 167.8 (C=O), 71.0 (OCH2CO), 48.04 (NCH), 46.0 (NCH), 21.0 (CH(CH3)2), 20.6
(CH(CH3)2); HRMS (clcd 301.2486) 301.2651
Tetra-n-Butyl DiGlycolAmide (TnBDGA): The title compound
was prepared from diglycolic acid (1.365g, 10.18mmol) and dibutyl
amine (4mL, 3g, 23.74mmol) following the general procedure to
give a yellow oil (2.88g, 8.08mmol, 80% yield); 1H NMR (400MHz, CDCl3) δ 4.27 (4H, s,
OCH2CO), 3.21 (8H, dt, NCH2, J=47.7, 7.7Hz), 1.48 (8H, m, CH2CH2CH2CH3), 1.27 (8H, m,
CH2CH2CH2CH3), 0.88 (12H, m, CH3);
13
C NMR (100MHz, CDCl3) δ 168.5 (C=O), 69.0
(OCH2CO), 46.6 (NCH2), 45.4 (NCH2), 31.0 (CH2CH2CH2CH3), 29.7 (CH2CH2CH2CH3), 20.2
(CH2CH2CH2CH3), 20.0 (CH2CH2CH2CH3), 13.8 (CH3), 13.7 (CH3); HRMS (clcd 357.3112)
357.3309
Tetra-iso-Butyl DiglycolAmide (TiBDGA): The title compound was
prepared from diglycolic acid (1.341g, 10.00mmol) and di-iso-butyl
amine (4.4mL, 3.23g, 25.5mmol) following the general procedure to
give a yellow oil (2.581g, 7.22mmol, 72% yield); 1H NMR (400MHz, CDCl3) δ 4.33 (4H, s,
OCH2CO), 3.09 (8H, dd, N(CH2CH(CH3)2)2, J=62.3, 7.6Hz), 1.93 (4H, dm, N(CH2CH(CH3)2)2,
J=41.2Hz); 13C NMR (100MHz, CDCl3) δ 168.2 (C=O), 70.3 (OCH2CO), 47.3 (NCH), 46.2
(NCH), 23.4 (CH2CH(CH3)2), 22.7 (CH2CH(CH3)2), 21.0 (CH(CH3)2), 20.6 (CH(CH3)2);
HRMS (clcd 357.3112) 357.3302
Tetra-sec-Butyl DiGlycolAmide (TsBDGA): The title compound was
prepared from diglycolic acid (1.356g, 10.mmol) and di-sec-butyl
amine (4.3mL, 3.331g, 25mmol) following the general procedure. The
residue was purified by flash chromatography (cyclohexane/ethyl acetate 80/20), then a second
flash chromatography was done (cyclohexane/ethyl acetate 70/30) to give a colorless oil
(1.721g, 4.8mmol, 48% yield); 1H NMR (400MHz, CDCl3) δ 4.26-4.15 (4H, m, OCH2CO),
3.54 (2H, br, NCH(CH3)CH2CH3), 2.96 (2H, br, NCHCH3CH2), 2.13-1.38 (8H, m,
NCH(CH3)CH2CH3), 1.35-1.10 (12H, m, NCH(CH3)CH2CH3), 0.91-0.79 (12H, m,
NCH(CH3)CH2CH3);
C NMR (100MHz, CDCl3) δ 168.5 (C=O), 168.4 (C=O), 70.7
13
(OCH2CO), 54.3 (NCH(CH3)CH2CH3), 52.7 (NCH(CH3)CH2CH3), 52.5 (NCH(CH3)CH2CH3),
28.1 (NCH(CH3)CH2CH3), 28.0 (NCH(CH3)CH2CH3), 27.7 (NCH(CH3)CH2CH3), 27.6
(NCH(CH3)CH2CH3),
19.4
(NCH(CH3)CH2CH3),
19.1
(NCH(CH3)CH2CH3),
17.9
(NCH(CH3)CH2CH3),
12.4
(NCH(CH3)CH2CH3),
12.2
(NCH(CH3)CH2CH3),
11.7
(NCH(CH3)CH2CH3); HRMS (clcd 357.3112) 357.3301