Fortier et al.
o-F). 13C{1H} (125 MHz, 22 °C, C6D6/THF-d8): δ 31.68 (CCH3).
IR (KBr pellet, cm-1): 3370 (w), 2985 (w), 1651 (w), 1631 (w),
1518 (s), 1479 (s), 1378 (m), 1315 (m), 1249 (w), 1172 (s), 1022
(s), 995 (s), 896 (s, vasym UdO), 854 (m), 739 (m), 651 (m), 479
(m). Anal. Calcd for C20H20F10O6U: C, 30.62; H, 2.58. Found: C,
30.26; H, 2.35.
turned dark-red. The solvent was then removed in vacuo to yield
a black solid, which was redissolved in pentane (3 mL) and stored
at -25 °C for 3 days. This resulted in the deposition of a few dark-
red crystals, which were collected and dried under vacuum. The
solid-state molecular structure was determined by X-ray crystal-
lographic analysis. Subsequent attempts to reproduce this material
for further characterization were unsuccessful.
UO2(OC6F5)2(DME) (5). To a vial containing C6F5OH (0.084
g, 0.456 mmol) and DME (0.024 mL) was added U(OtBu)6 (0.042
g, 0.062 mmol) dissolved in hexanes (5 mL). The resulting dark-
red solution gradually lightened over the course of 12 h, affording
a red-orange solution concomitant with the deposition of an orange
powder. The supernatant was decanted off, and the powder was
washed with hexanes (2 × 2 mL) and dried under vacuum: 0.023
[Li(DME)3]2[U(OC6F5)6] (7). To a solution of [Li(THF)]2-
[U(OtBu)6] (0.200 g, 0.240 mmol) in diethyl ether (5 mL) was added
C6F5OH (0.441 g, 2.400 mmol) dissolved in diethyl ether (1 mL).
The solution immediately turned green-amber. After stirring for
4 h the solvent was removed in vacuo to yield an amber oil.
Addition of DME (5 mL), followed by stirring for 1 h, resulted in
the formation of a pale-pink powder. The pale-pink powder was
subsequently washed with hexanes (3 × 4 mL). The powder was
redissolved in diethyl ether (9 mL) and DME (0.5 mL) and layered
with hexanes (9 mL). This solution was stored at -25 °C for 48 h
to yield a pale-pink crystalline solid, which was washed with
hexanes (4 mL) and dried under vacuum: 0.176 g, 81% yield.
Crystals of 7 turned opaque and pale-blue upon application of
1
g, 51% yield. H NMR (500 MHz, 22 °C, C6D6/THF-d8): δ 3.12
(s, 6H, DME), 3.31 (s, 4H, DME). 19F{1H} NMR (470 MHz, 22
°C, C6D6/THF-d8): δ -116.16 (br s, 2F, p-F), -106.42 (br s, 4F,
m-F), -102.42 (d, 4F, 3JFF ) 12.1 Hz, o-F). IR (KBr pellet, cm-1):
3435 (w), 2959 (w), 2673 (w), 2473 (w), 1652 (w), 1628 (w), 1516
(s), 1485 (s), 1372 (w), 1315 (w), 1250 (w), 1179 (m, νCO), 1167
(m), 1085 (m), 1025 (s), 997 (s), 935 (m, νasymUdO), 864 (m),
656 (m), 479 (m), 463 (m), 431 (m).
1
vacuum. H NMR (400 MHz, 22 °C, CD2Cl2): δ 2.42 (br s, 24H,
Synthesis of C6F518OH ·0.5DME. The synthesis of C6F518OH
was adapted from a previously reported procedure.113 To a 100
mL Schlenk flask equipped with a reflux condenser were added
KH (0.350 g, 8.54 mmol) and DME (20 mL). The suspension was
cooled to -78 °C, and H218O (0.22 mL, 11.0 mmol) was added
dropwise. The mixture was allowed to warm to room temperature,
and C6F6 (0.5 mL, 4.33 mmol) was added, whereupon the reaction
mixture was refluxed for 15 h. Upon cooling, the solution was
filtered, and the DME was removed in vacuo yielding
[K(DME)x][18OC6F5] as a white solid. This solid was subsequently
dissolved in Et2O (10 mL) and treated with HCl (3.5 mL, 1 M in
Et2O). The resulting suspension was filtered through a Celite column
(3 cm × 2 cm) supported on a glass frit, and the filtrate was
removed in vacuo yielding C6F518OH·0.5DME as a white solid.
0.450 g, 45% yield. 1H NMR (400 MHz, 22 °C, C6D6): δ 3.07 (s,
3H, DME), 3.26 (s, 2H, DME), 4.50 (s, 1H, OH). 19F{1H} NMR
7
DME), 3.02 (s, 36H, DME). Li{1H} NMR (194 MHz, 22 °C,
CD2Cl2): δ -22.55 (br s). 19F{1H} (376 MHz, 22 °C, CD2Cl2): δ
-111.50 (s, 6F, p-F), -107.84 (s, 12F, m-F), -105.22 (s, 12F,
m-F). Anal. Calcd for [Li(DME)3]2[U(OC6F5)6], C60H60F30Li2O18U:
C, 38.11; H, 3.20. Anal. Calcd for [Li(DME)]2[U(OC6F5)6],
C44H20F30Li2O10U: C, 34.53; H, 1.32. Found: C, 34.14; H, 1.34.
[Li(DME)3][U(OC6F5)6] (8). To a solution of 7 (0.150 g, 0.080
mmol) in CH2Cl2 (7 mL) was added AgOTf (0.041 g, 0.160 mmol).
The reaction mixture immediately turned dark-red. Stirring was
continued for 24 h at room temperature. The solution was then
filtered through a Celite column (2 cm × 0.5 cm) supported on
glass wool, affording a dark-red filtrate. The filtrate was layered
with hexanes (10 mL) and stored at -25 °C for 24 h, which resulted
in the deposition of dark-red crystals. The solid was washed with
hexanes (3 × 4 mL) and dried under vacuum: 0.103 g, 81% yield.
1H NMR (400 MHz, 22 °C, CD2Cl2): δ 3.43 (s, 18H, DME), 3.60
(s, 12H, DME). 7Li{1H} NMR (194 MHz, 22 °C, CD2Cl2): δ -1.90
(470 MHz, 22 °C, C6D6): δ -107.43 (triplet of triplets, 1F, 3JFF
)
22.5 Hz, 4JFF ) 6.2 Hz, p-F), -102.54 (t, 2F, 3JFF ) 20.4 Hz, m-F),
(s). 19F{1H} (376 MHz, 22 °C, CD2Cl2): δ -105.19 (t, 6F, 3JFF
)
3
4
21.3 Hz, p-F), -104.16 (t, 12F, 3JFF ) 16.8 Hz, m-F), -99.03 (d,
-101.24 (dd, 2F, JFF ) 18.1 Hz, JFF ) 5.5 Hz, o-F). MS (EI):
m/z 186 (H18OC6F5), 155 (C5F5), 136 (C5F4), 117 (C5F3), 105 (C4F3),
93 (C3F3), 86 (C4F2), 69 (CF3).
3
12F, JFF ) 11.6 Hz, o-F). Anal. Calcd for C48H30F30LiO12U: C,
35.73; H, 1.88. Found: C, 35.35; H, 2.02.
UO2(18OC6F5)2(DME) (5-18O). To a solution of U(OtBu)6 (0.035
g, 0.052 mmol) in hexanes (5 mL) was added C6F518OH·0.5DME
(0.073 g, 0.316 mmol) dissolved in hexanes (1 mL). The resulting
dark-red solution gradually lightened over the course of 12 h,
affording a red-orange solution concomitant with the deposition of
an orange powder. The supernatant was decanted off, and the
powder was washed with hexanes (2 × 2 mL) and dried under
[Ag(η2-C7H8)2(DME)][U(OC6F5)6] (9). To a stirring solution of
7 (0.210 g, 0.111 mmol) in toluene (4 mL) was added AgOTf (0.071
g, 0.276 mmol). The reaction mixture immediately turned dark-
red. Stirring was continued for 12 h at room temperature, whereupon
the solution was filtered through a Celite column (2 cm × 0.5 cm)
supported on glass wool, affording a dark-red filtrate. The solvent
was removed in vacuo to give a tacky red solid. The solid was
redissolved in toluene (4 mL) and again filtered through a Celite
column (2 cm × 0.5 cm). The filtrate was layered with hexanes
(10 mL) and stored at -25 °C for 12 h, resulting in the deposition
of dark-red crystals. The solid was washed with hexanes (3 × 4
mL) and dried under vacuum: 0.180 g, 60% yield. Crystals of 9
1
vacuum: 0.021 g, 55% yield. H NMR (500 MHz, 22 °C, C6D6/
THF-d8): δ 3.15 (s, 6H, DME), 3.31 (s, 4H, DME). 19F{1H} NMR
(470 MHz, 22 °C, C6D6/THF-d8): δ -113.94 (br s, 2F, p-F),
-105.21 (t, 4F, 3JFF ) 21.4 Hz, m-F), -102.32 (d, 4F, 3JFF ) 18.0
Hz, o-F). IR (KBr pellet, cm-1): 3424 (w), 2959 (w), 2665 (w),
2460 (w), 1652 (w), 1628 (w), 1513 (s), 1478 (s), 1372 (w), 1313
(w), 1250 (w), 1169 (m), 1158 (m, νCO), 1085 (m), 1021 (s), 994
(s), 935 (m, νasymUdO), 864 (m), 642 (m), 475 (m), 462 (m), 419
(m).
1
turned opaque upon application of vacuum. H NMR (400 MHz,
22 °C, CD2Cl2): δ 2.37 (s, 6H, toluene CH3), 3.45 (s, 6H, DME),
3.62 (s, 4H, DME), 7.19 (m, 2H, toluene CH), 7.25 (m, 4H, toluene
CH), 7.30 (m, 4H, toluene CH). 19F{1H} (376 MHz, 22 °C, CD2Cl2):
U(OtBu)2(OC6F5)4 (6). To a stirring solution of U(OtBu)6 (0.015
g, 0.022 mmol) in pentane (3 mL) was added C6F5OH (0.041 g,
0.227 mmol) dissolved in pentane (1 mL). The solution immediately
3
3
δ -105.15 (t, 6F, JFF ) 20.7 Hz, p-F), -104.13 (t, 12F, JHH
)
16.0 Hz, m-F), -98.99 (d, 12F, 3JFF ) 13.0 Hz, o-F). Anal. Calcd
for [Ag(η2-C7H8)2(DME)][U(OC6F5)6], C54H26AgF30O8U: C, 37.73;
H, 1.53. Anal. Calcd for [Ag(η2-C7H8)(DME)][U(OC6F5)6],
C47H18AgF30O8U: C, 34.71; H, 1.12. Found: C, 34.76; H, 1.43.
(113) Pummer, W. J.; Wall, L. A. Science 1958, 127, 643–644.
3010 Inorganic Chemistry, Vol. 48, No. 7, 2009