3.2.3. Preparation of [Ln(hfac)3{(ArF)3PO}(H2O)], Ln = Sm3+, Eu3+, Tb3+, Er3+, Yb3+ (1–5) from Ln(hfac)3·2H2O
In air, Ln(hfac)3·2H2O (0.31 mmol) and FPh3PO (0.31 mmol) were added to a round bottomed flask and dissolved in CH2Cl2 (150 mL). The reaction mixture was sonicated for 1 h. The reaction mixture was then filtered under gravity. All volatiles were removed by rotary evaporation and the resultant crude powders recrystallised from CH2Cl2 by slow evaporation and the crystalline products filtered under gravity, washed with CH2Cl2 and dried in vacuo. Once isolated, all the complexes are air stable for extended time periods (>4 years) are moderately soluble in acetone and sparingly soluble in CH2Cl2 and CHCl3 precluding acquisition of NMR data in some cases.
[Sm(hfac)3{(ArF)3PO}(H2O)] (1): Isolated in 41% yield as pale yellow crystals (170 mg). NMR/CDCl3 (400 MHz) δH: 7.51 (s, CH-hfac); δF: −77.79 (s, 18F, CF3-hfac), −131.37 (s, 6F) ortho-CF), −140.37 (br, 3F, para-CF), −157.05 (m, 6F, meta-CF) δP {1H}: −7.44 (s, (ArF)3PO). UV–vis (CH2Cl2) λ = 234 nm ((ArF)3PO), 306 nm ((ArF)3PO and hfac). Anal. Calcd. For C33H5O8F33PSm: C 29.63, H 0.37, N 0.0, P 2.31, Sm 11.24. Found: C 29.52, H 0.0, N 0.0, P 2.06, Sm 11.63.
[Eu(hfac)3{(ArF)3PO}(H2O)] (2): Isolated in 38% yield as colourless crystals (158 mg). NMR/CDCl3 (400 MHz) δH, δF, δP {1H}: no signals observed. UV–vis (CH2Cl2) λ = 232 nm ((ArF)3PO), 301 nm ((ArF)3PO and hfac). Anal. Calcd. For C33H5O8F33PEu: C 29.59, H 0.38, N 0.0. Found: C 28.64, H 0.14, N 0.0.
[Tb(hfac)3{(ArF)3PO}(H2O)] (3): Isolated in 49% yield as pale green crystals (205 mg). NMR/CDCl3 (400 MHz) δH: −0.19 (br, CH-hfac); δF: −45.54 (br, CH-hfac), −131.88 (br, ortho-CF), −141.34 (br, para-CF), −157.33 (br, meta–CF). δP {1H}: −10.06 (br). UV–vis (CH2Cl2) λ = 231 nm ((ArF)3PO), 303 nm ((ArF)3PO and hfac). Anal. Calcd. For C33H5O8F33PTb: C 29.44, H 0.37, N 0.0, P 2.30, Tb 11.80. Found: C 29.32, H 0.0, N 0.0, P 1.99, Tb 10.80.
[Er(hfac)3{(ArF)3PO}(H2O)] (4): Isolated in 49% yield as pink crystals (206 mg). NMR/CDCl3 (400 MHz) δH: no signal observed; δF: −94.62 (br, CF3-hfac), −137.20 (br, ortho/meta/para-CF), −153.32 (br, 6F, ortho/meta/para-CF); δP {1H}: no signal observed. UV–vis (CH2Cl2) λ = 233 nm ((ArF)3PO), 302 nm ((ArF)3PO and hfac). Anal. Calcd. For C33H5O8F33PEr: C 29.25, H 0.37, N 0.0, P 2.29, Er 12.38. Found: C 29.28, H 0.0, N 0.0, P 1.97, Er 12.10.
[Yb(hfac)3{(ArF)3PO}(H2O)] (5): Isolated in 59% yield as colourless crystals (249 mg). NMR/CDCl3 (400 MHz) δH: 8.07 (br, CH-hfac); δF: −87.83 (s, 2F, ortho/meta CF), −123.75 (br, CF3-hfac), −138.98 (s, 1F, para-CF), −155.68 (s, 2F, ortho/meta CF); δP {1H}: no signal observed. UV–vis (CH2Cl2) λ = 232 ((ArF)3PO), 302 nm ((ArF)3PO and hfac). Anal. Calcd. For C33H5O8F33PYb: C 29.14, H 0.37, N 0.0, P 2.27. Found: C 28.82, H 0.0, N 0.0, P 1.73.
[Tm(hfac)3{(ArF)3PO}(H2O)]: Isolated in 26% yield as colourless crystals (109 mg). Anal. Calcd. For C33H5O8F33PTm: C 29.22, H 0.37, N 0.0, P 2.28, Tm 12.45. Found: C 29.18, H 0.0, N 0.0, P 2.05, Tm 12.36.
3.2.5. Preparation of [Ln(F7-acac)3{(ArF)3PO}2] Ln = Sm3+, Eu3+, Tb3+, Er3+, Yb3+ (6–10) from Ln(OAc)3·xH2O under N2
Under N2, an oven dried Schlenk was charged with 0.33 mmol of the appropriate lanthanide acetate hydrate (Ln(OAc)3·xH2O) and 0.66 mmol (142 mg) (ArF)3PO. 25 mL of dry CH2Cl2 was then added by cannula or syringe. 1,1,1,3,5,5,5-heptfluoro-2,4-pentanedione (0.94 mmol) was subsequently rapidly added and the reaction mixture heated at reflux temperature for 1 hour under a flow of N2, then cooled to room temperature. After this time, dry pentane (40 mL) was added and the Schlenk flask placed in the freezer at −18 °C. After one week, the crystalline products were isolated by filtration, washed with cold CH2Cl2 and dried under vacuum suction to yield the title compounds. The products are slightly hygroscopic when stored under ambient conditions for extended periods of time (>1 year). All complexes are soluble in acetone and sparingly soluble in CH2Cl2 and CHCl3.
[Sm(F7-acac)3{(ArF)3PO}2] (6): Isolated in 42% yield as a pale yellow crystalline solid (289 mg). NMR/d6-acetone (200 MHz) δF: −74.67 (d, 18F, 4JFF = 18.3 Hz, CF3-hfac), −134.15 (d, 12F, 3JFF = 10.9 Hz, 4JFF = 8.1 Hz, ortho-CF), −145.68 (m, 6F, para-CF), −161.28 (m, 12F, meta-CF), −192.30 (br, 3H, CF F7-acac); δP {1H}: −9.20 (s, (ArF)3PO). UV–vis (CH2Cl2) λ = 230, 272 nm ((ArF)3PO), 328, 356 (sh) nm (F7-acac). Anal. Calcd. For C51O8F51P2Sm·2CH2Cl2: C 30.43, H 0.19, N 0.0, Sm 7.20. Found: C 30.25, H 0.0, N 0.0, Sm 6.85.
[Eu(F7-acac)3{(ArF)3PO}2] (7): Isolated in 37% yield as a pale yellow crystalline solid (242 mg). NMR/d6-acetone (200 MHz) δF: −78.14 (d, 18F, 4JFF = 17.4 Hz, CF3 F7-acac), −134.11 (dd, 12F, 3JFF = 22.0 Hz, 4JFF = 1.9 Hz, ortho-CF), −145.68 (m, 6F, para-CF), −161.29 (m, 12F, meta-CF), −170.01 (m, 3F, CF F7-acac); δP {1H}: −7.80 (s, (ArF)3PO). UV–vis (CH2Cl2) λ = 232, 274 nm ((ArF)3PO), 324, 358 (sh) nm (F7-acac). For C51O8F51P2Eu·CH2Cl2: C 31.10, H 0.1, N 0.0, Eu 7.57. Found: C 30.73, H 0.0, N 0.0, Eu 8.57.
[Tb(F7-acac)3{(ArF)3PO}2] (8): Isolated in 47% yield as a pale yellow crystalline solid (312 mg). NMR/d6-acetone (200 MHz) δF: −58.84 (br, CF3 F7-acac), −134.20 (d, 6F, 4JFF = 20.7 Hz, ortho-CF), −145.65 (m, 3F, para-CF), −161.28 (m, 6F, meta-CF), −108.00 (br, CF F7-acac); δP{1H}: −11.61 (br, (ArF)3PO). UV–vis (CH2Cl2) λ = 230, 276 nm ((ArF)3PO), 330 nm (F7-acac). Anal. Calcd. For C51O8F51P2Tb·CH2Cl2: C 30.99, H 0.1, N 0.0, Tb 7.89. Found: C 30.92, H 0.0, N 0.0, Tb 7.20.
[Er(F7-acac)3{(ArF)3PO}2] (9): Isolated in 40% yield as a pale yellow crystalline solid (289 mg). NMR/d6-acetone (200 MHz) δF: −87.28 (br, CF3 F7-acac), −133.90 (d, 6H, 4JFF = 21.8 Hz, ortho-CF), −145.47 (m, 3H, para-CF), −161.27 (m, 6H, meta-CF), −213.41 (br, CF F7-acac); δP{1H}: −10.63 (s, (ArF)3PO). UV–vis (CH2Cl2) λ = 232, 274 nm ((ArF)3PO), 322, 354 (sh) nm (F7-acac). Anal. Calcd. For C51O8F51P2Er·3CH2Cl2: C 29.57, H 0.28, N 0.0, Er 7.63. Found: C 29.10, H 0.0, N 0.0, Er 7.22.
[Yb(F7-acac)3{(ArF)3PO}2] (10): Isolated in 27% yield as a pale yellow crystalline solid (213 mg). NMR/d6-acetone (200 MHz) δF: −87.37 (br, CF3 F7-acac), −133.99 (d, 6H, 4JFF = 20.0 Hz, ortho-CF), −145.66 (m, para-CF), −161.28 (m, 6H, meta-CF), −208.20 (br, CF F7-acac); δP {1H}: −8.93 (br, (ArF)3PO). UV–vis (CH2Cl2) λ = 230, 274 nm ((ArF)3PO), 322, 354 (sh) nm (F7-acac). Anal. Calcd. For C51O8F51P2Yb·5CH2Cl2: C 28.39, H 0.43, N 0.0, Yb 7.30. Found: C 27.82, H 0.0, N 0.0, Yb 6.98.
[Tm(F7-acac)3{(ArF)3PO}2]: Isolated in 48% yield as a white crystalline solid (321 mg). NMR/d6-acetone (200 MHz) δF: −98.08 (br, CF3 F7-acac), −133.88 (s, 6H, ortho-CF), −145.47 (m, para-CF), −161.27 (m, 6H, meta-CF), −245.04 (br, CF F7-acac); δP: −9.10 (br, (ArF)3PO). Anal. Calcd. For C51O8F51P2Tm·CH2Cl2: C 30.84, H 0.0, N 0.0, Tm 8.34. Found: C 30.47, H 0.0, N 0.0, Tm 8.74.