ELECTRONIC SUPPLEMENTARY MATERIAL

Journal title: Journal of Radioanalytical and Nuclear Chemistry

Article Title:Hydrophilic 1,10-phenanthroline derivatives for selective Am(III) stripping into aqueous solutions

Stefano Scaravaggia, Elena Macerataa,*, Michele Gallettaa, Eros Mossinia, Alessandro Casnatib, Mattia Anselmib, Francesco Sansoneb, Mario Mariania

aDepartmentof Energy, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy; Fax: +39.02.23996309; Tel: +39.02.23996385;

b Department of Chemistry, University of Parma, Parco Area delleScienze 17/a, 43124 Parma, Italy; Fax: +39.0521.905472; Tel:+39.0521.905458;

*Corresponding author e-mail:

INDEX

Details of synthesis

Table ESM1. Results of the screening tests of 2 and 3. Organic phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v; Aqueous phase: 0.017-0.15Mligand,0-0.5M NH4NO3 and 241Am and 152Eu in 0.1-3.82M HNO3init. T = room temperature.

Figure ESM1. Equilibrium HNO3 concentration of the stripping phase as a function of initial aqueous nitric acid concentration: Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am and 152Eu 3M HNO3 solution; Aqueous Phase: 0.1-3M HNO3init.

Figure ESM2. Distribution ratios of Am (∆) and Eu (▲) and SFEu/Am () as a function of mixing time. Experimental conditions: Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am and 152Eu from the extraction step; Aqueous Phase: 0.01M 3 solution in 0.1M HNO3init.

Figure ESM3. Distribution ratios of Am (∆) and Eu (▲) and SFEu/Am() as a function of mixing time. Experimental conditions: Organic Phase: 0.05M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am, 152Eu, Y and all Lns; Aqueous Phase: 0.005M1 in 1M HNO3init.

Table ESM2. Results of the stripping tests with ligand3 for Am and Eu.Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded in a previous extraction step with HAR elements; Aqueous phase: 0.01-0.03M 3 and 0-0.2M NH4NO3 in water or 0.1-0.2M HNO3init.

Details of synthesis

Synthesis of 1,3-Propanediol, 2-[(acetyloxy)methyl]-2-benzyloxycarbonylamino-, 1,3-diacetate (5)

To a solution of Cbz-TRIS 4[45] (1.49 g, 5.83 mmol) in dry pyridine (20 mL) was added acetic anhydride (16.5 mL). The reaction mixture was stirred at room temperature for 15h. Then the solvents were distilled off and the residue submitted to column chromatography (SiO2: hexane/AcOEt = 60:40). A colourless oil was obtained (1.89 g, 85%). 1H NMR (CDCl3, 300MHz, 300K)  = 7.35 (5H, s, ArH), 5.29 (1H, s, NH), 4.37 (6H, s, CH2), 2.03 (9H, s, CH3). ESI-MS (+): 404.5 [M+Na]+.

Synthesis of 1,3-Propanediol, 2-[(acetyloxy)methyl]-2-amino-, 1,3-diacetate (6)

A solution of compound 5 (1.89g, 4.88 mmol) and Pd/C (20 mg) in 20 mL of AcOEt was stirred under H2 atmosphere (3 bars) at room temperature for 24h. Pd/C was filtered off and the solvent removed from the filtrate at reduced pressure, giving compound 6 (1.11 g, 91%) as a pale yellow oil. 1H NMR (CDCl3, 300MHz, 300K)  = 3.96 (6H, s, CH2), 1.95 (9H, s, CH3). ESI-MS (+): 270.3 [M+Na]+.

Synthesis of 1,10-phenanthroline-2,9-dicarboxamide, N2,N9-bis[1,3-diacetyloxy-2-(acetyloxymethyl)propan-2-yl] (7)

Phenanthroline diacid2 (50mg, 0.186 mmol) and N-isobutoxycarbonyl-2-isobutoxy-1,2-dihydro-quinoline (IDDQ, 158 mg, 0.522 mmol) were dissolved in acetonitrile (10 mL) under nitrogen atmosphere and stirred for 30 min. Then triacetoxy-TRIS 6 (115 mg, 0.466 mmol) was added and the reaction mixture was stirred for 18 h. Acetonitrile was removed at reduced pressure, the residue was dissolved in AcOEt (20 mL) and washed with 0.1M HCl aqueous solution (20 mL) and water (20 mL). The organic phase was separated and the solvent removed under reduced pressure. Pure compound 7 (101 mg, 75%) was obtained as a sticky yellowish solid after column chromatography (SiO2: AcOEt/toluene = 80/20). 1H NMR (CDCl3, 400MHz, 300K)  = 8.82 (2H, s, NH), 8.56 (2H, d, J = 8.3 Hz, Phen-H), 8.44 (2H, d, J = 8.3 Hz, Phen-H), 7.93 (2H, s, Phen-H), 4.69 (12H, s, CH2), 2.04 (18H, s, CH3CO). ESI-MS (+): 749.8 [M+Na]+.

Synthesis of 1,10-phenanthroline-2,9-dicarboxamide, N2,N9-bis[1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl] (1)

A sample of compound 7 (178 mg, 245 mmol) was dissolved in methanol (10 mL) and added of solid CH3ONa up to pH = 8. The reaction mixture was stirred at rt for 2h. Then Amberlite IR120 was added till the solution reached pH = 7. The solution was separated, the resin washed with methanol and the filtrates collected. Pure product 1 (77 mg, 63%) was obtained by removal of methanol at the rotavapor at rt. 1H NMR (DMSO-d6, 300MHz, 300K)  = 8.76 (2H, d, J = 8.4 Hz, Phen-H), 8.57 (2H, s, NH), 8.49 (2H, d, J = 8.4 Hz, Phen-H), 8.2 (2H, s, Phen-H), 4.99 (6H, t, J = 5.7 Hz, OH), 3.85 (12H, d, J = 5.7 Hz, CH2). 13C NMR (DMSO-d6, 100MHz, 300K)  = 164.0 (C=O), 150.6 (C2,9), 143.9 (Cquat), 138.9 (C4,7), 130.9 and 128.6 (C5,6 and Cquat), 121.5 (C3,8), 62.4 (CN), 60.6 (CH2). ESI-MS (+): 497.2 [M+Na]+.

Table ESM1. Results of the screening tests of 2 and 3. Organic phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v; Aqueous phase: 0.017-0.15Mligand,0-0.5M NH4NO3 and 241Am and 152Eu in 0.1-3.82M HNO3init. T = room temperature.

[Ligand] M / [NH4NO3] M / [HNO3]init M
0.1 / 0.5 / 1 / 3.82
0a / 0 / 43.7 / >100 / >100 / DEu
DAm
SFEu/Am
6.46 / 54.1 / >100 / - / DAm
SFEu/Am
6.76 / >1.85 / n.c. / SFEu/Am
0.5 / >100 / >100 / >100 / DEu
32.4 / >100 / >100 / - / DAm
3.09 / n.c. / n.c. / SFEu/Am
3 / 0.02 / 0.5 / 2.82 / DEu
0.14 / - / - / - / DAm
21.2 / SFEu/Am
0.05b / 0 / 0.41 / >100 / >100 / DEu
0.03 / 11.5 / >100 / - / DAm
12.8 / >8.7 / n.c. / SFEu/Am
0.15b / 0.5 / 0.01 / 23.2 / >100 / DEu
0.01 / 0.94 / 23.5 / - / DAm
n.c. / 24.8 / >4.26 / SFEu/Am
2 / 0.017b / 0 / > 100 / DEu
c / c / c / > 100 / DAm
n.c. / SFEu/Am

a no ligand in the aqueous phase;

b cloudy solutions or presence of precipitate;

c not performed due to insolubility of the ligand;

n.c.:not computed;

[HNO3]init: nitric acid concentration of the stripping phase before the contact with the loaded organic phase

Figure ESM1. Equilibrium HNO3 concentration of the stripping phase as a function of initial aqueous nitric acid concentration: Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am and 152Eu 3M HNO3 solution; Aqueous Phase: 0.1-3M HNO3init.

FigureESM2. Distribution ratios of Am (∆) and Eu (▲) and SFEu/Am () as a function of mixing time. Experimental conditions: Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am and 152Eu from the extraction step; Aqueous Phase: 0.01M 3 solution in 0.1M HNO3init.

Figure ESM3.Distribution ratios of Am (∆) and Eu (▲) and SFEu/Am() as a function of mixing time. Experimental conditions: Organic Phase: 0.05M TODGA in kerosene/1-octanol 95:5 v/v loaded with 241Am, 152Eu, Y and allLns; Aqueous Phase: 0.005M 1 in 1M HNO3init.

Table ESM2. Results of the stripping tests with ligand3 for Am and Eu.Organic Phase: 0.2M TODGA in kerosene/1-octanol 95:5 v/v loaded in a previous extraction step with HAR elements; Aqueous phase: 0.01-0.03M 3 and 0-0.2M NH4NO3 in water or 0.1-0.2M HNO3init.

[3] M / [NH4NO3] M / [HNO3]init M
water / 0.1 / 0.2
0 / 0 / 48.1 / 90.3 / DEu
6.91 / 12.9 / DAm
6.96 / 7.03 / SFEu/Am
0.1 / 33.7 / 55.7 / DEu
4.81 / 7.76 / DAm
7.01 / 7.18 / SFEu/Am
0.2 / 82.7 / >100 / DEu
11.2 / 18.2 / DAm
7.36 / 5.50 / SFEu/Am
0.01 / 0 / 24.5 / DEu
2.22 / DAm
11.0 / SFEu/Am
0.1 / 79.5 / DEu
5.38 / DAm
14.8 / SFEu/Am
0.02a / 0.1 / 17.3 / 27.2 / DEu
1.31 / 1.38 / DAm
13.3 / 19.8 / SFEu/Am
0.2 / 41.3 / DEu
2.48 / DAm
16.6 / SFEu/Am
0.03a / 0 / 31.4 / DEu
1.74 / DAm
18.0 / SFEu/Am
0.1 / 27.9 / DEu
1.69 / DAm
16.5 / SFEu/Am
0.2 / 56.0 / DEu
3.03 / DAm
18.5 / SFEu/Am

a extraction test performed at T = 50°C

S1