Remote handling systems for the ISAC and ARIEL high-power fission and spallation ISOL target facilities at TRIUMF

Chemical Promiscuity of Non-Macrocyclic Multidentate Chelating Ligands for Radiometal Ions: H4neunpa-NH2 vs H4noneunpa

“…Chelating Ligand Synthesis. tert-Butyl(2-(bis(2-aminoethyl)amino)ethyl)carbamate (1). Tris(2-aminoethyl)amine (tren) (5.10 g, 35.0 mmol, 6.3 equiv) was dissolved in dry dioxane (30 mL) under argon, and a solution of di-tert-butyl dicarbonate (1.20 g, 5.50 mmol) in dry dioxane (20 mL) was added dropwise over 1.5 h at RT.…”

“…The crude product was purified via silica gel chromatography (CombiFlash automated purification system; CH 2 Cl 2 /MeOH/NH 4 OH (10:4:1)) to yield the title compound as a pale-yellow oil (1.01 g, 74%). 1 H NMR (300 MHz, CDCl 3 , 298 K) 5.46 (1H, br s, 2 −NH), 3.09 (2H, m, 3 −CH 2 ), 2.67 (4H, t, J = 5.9 Hz, 6 −CH 2 ), 2.49−2.43 (6H, m, 4− and 5 −CH 2 ), 2.06 (4H, br s, 7 −NH 2 ), 1.36 (9H, s, 1 −C(CH 3 ) 3 ). 13 (40 mL) and cooled to 0 °C.…”

“…The title compound was obtained as an off-white fluffy solid (2.16 g, 90%). 1 H NMR (300 MHz, CDCl 3 , 298 K) 8.09 (2H, dd, 3 J = 9.0 Hz, 4 J = 3.0 Hz, 11 −CH), 7.82 (2H, dd, 3 J = 9.0 Hz, 4 J = 3.0 Hz, 8 −CH), 7.76−7.69 (4H, m, 9− and 10 −CH), 5.88 (2H, br s, 7 −NH), 4.94 (1H, br s, 2 −NH), 3.09−3.07 (6H, m, 3− and 6 −CH 2 ), 2.62 (4H, t, 3 J = 6.0 Hz, 5 −CH 2 ), 2.52 (2H, t, 3 J = 6.0 Hz, 4 −CH 2 ), 1.38 (9H, s, 1 −C(CH 3 ) 3 ). 13 58 mmol) was dissolved in dry MeCN (40 mL), and diisopropylethylamine (dipea) (1.80 mL, 1.34 g, 10.3 mmol, 4.0 equiv) was added to give a pale-orange solution.…”

“…The title compound was isolated as an off-white fluffy solid (1.31 g, 60%). 1 H NMR (300 MHz, CDCl 3 , 298 K) 8.03 (2H, dd, 3 J = 5.9 Hz, 4 J = 3.4 Hz, 11 −CH), 7.65 (4H, m, 8− and 9 −CH), 7.55 (2H, dd, 3 J = 5.9 Hz, 4 J = 3.4 Hz, 10 −CH), 5.01 (1H, br s, 2 −NH), 4.06 (4H, s, 7 −CH 2 ), 3.42 (4H, t, 3 J = 6.8 Hz, 6 −CH 2 ), 3.09 (2H, q, 3 J = 5.7 Hz, 3 −CH 2 ), 2.68 (4H, t, 3 J = 6.8 Hz, 5 −CH 2 ), 2.54 (2H, t, 3 J = 5.8 Hz, 4 −CH 2 ), 1.38 (9H, s, 1 −C(CH 3 ) 3 ), 1.29 (18H, s, 12 −C(CH 3 ) 3 ). 13 were separated via centrifuge and the supernatant was removed.…”

“…The title compound was isolated as a pale-yellow oil (210 mg, 99%). 1 (5). Compound 4 (210 mg, 0.451 mmol) was dissolved in dry MeCN (10 mL), and K 2 CO 3 (250 mg, 1.80 mmol, 4.0 equiv) added to the stirred solution at RT.…”