Inorganic Chemistry
Article
diffractometer equipped with a copper lamp [λ(Cu Kα) = 1.5418 Å].
Measurements were performed in the 2θ range of 5−90° in
increments of 0.032° with a counting time of 0.3 s. The morphology
of the prepared powders was examined by high-resolution TEM and
SEM. TEM analysis was conducted using an FEI Tecnai G2 20 X-Twin
microscope equipped with an EDS microanalyzer and operating at 200
kV (resolution = 0.25 nm). SEM analysis was performed on a Hitachi
S-3400N microscope equipped with a Thermo Noran SIX EDS
system.
XRD data were collected using an Xcalibur Ruby or Xcalibur PX
diffractometer at 100 K for 1 and 8, 220 K for 2, 200 K for 3 and 7,
190 K for 4 and 9, and 90 K for 5 and 6.33 The experimental details
and crystal data are summarized in Table S3. The crystal structures
were solved using direct methods and refined by the full-matrix least-
squares method on F2 using the SHELXTL package.34 Non-H atoms
were refined with anisotropic thermal parameters. All H atoms were
positioned geometrically and added to the structure factor calculations
but were not refined. Molecular graphics were created using
DIAMOND (version 3.1e).35 Crystallographic data for the structural
analyses reported in this paper have been deposited with the
Cambridge Crystallographic Data Centre as CCDC 1558845−
consumed (typically within 24 h). The resulting yellow solution was
filtered off. The filtrate volume was reduced under a vacuum to 20 mL,
and then hexane (20 mL) was slowly added, forming a colorless layer
over the solution. Colorless crystals of 3 were formed at room
temperature within a few days (2−3). The crystals were collected,
washed with a mixture of EtOH and hexane (1:5, 3 × 5 mL), and dried
under vacuum. The resulting filtrate was concentrated to 10 mL and
left to produce another portion of crystalline materials. Overall yield:
1.09 g, 0.96 mmol, 73%. Anal. Calcd for C32H84O16Mg2Hf2: C, 34.00;
H, 7.49; Mg, 4.30; Hf, 31.57. Found: C, 34.06; H, 7.56; Mg, 4.33; Hf,
31.66. IR (cm−1, Nujol mull): 3126 (m), 2958 (vs), 2923 (vs), 2855
(vs), 2710 (m), 1463 (vs), 1375 (vs), 1282 (w), 1171 (vs), 1105 (vs),
1066 (vs), 922 (w), 893 (s), 874 (m), 721 (m), 640 (m), 517 (s), 465
1
(vs). H NMR (500 MHz, CDCl3, ppm): δ 5.36 (s, OH, 4H), 4.15,
4.07, 3.86 (m, CH2, 24H), 3.73 (q, J = 6.7 Hz, CH2, 8H), 1.23 (m,
CH3, 48H). 13C NMR (125 MHz, CDCl3, ppm): δ 64.6−59.2, 58.0
(CH2, 16C), 21.6−18.8, 18.5 (CH3, 16C).
Synthesis of [Ca6Ti4(μ6-O)2(μ4-O)2(μ3-OEt)12(OEt)12(EtOH)6Cl4]
(4). A Schlenk flask was charged with Cp2TiCl2 (1.66 g, 6.67 mmol),
metallic Ca (0.53 g, 13.22 mmol), EtOH (30 mL), and toluene (5
mL). The mixture was vigorously stirred at 65 °C until all metal was
consumed (typically within 2 h). During the reaction course, a dark-
red solution slowly changed to dark green, then brown, and finallylight
yellow. The resulting solution was filtered off, and the filtrate was
reduced under a vacuum to 20 mL and left to crystallize. After 12 h,
colorless crystals of 4 were collected, washed with hexane (3 × 5 mL),
and dried under vacuum. Yield: 0.56 g, 0.34 mmol, 21%. Calcd for
C44H116O26Cl4Ca6Ti4: C, 32.32; H, 7.15, Cl, 8.67; Ca, 14.71; Ti, 11.71.
Found: C, 32.30; H, 7.24, Cl, 8.68; Ca, 14.79; Ti, 11.78. IR (cm−1,
Nujol mull): 3290 (s), 2956 (vs), 2925 (vs), 2870 (vs), 2855 (vs),
2720 (w), 1922 (vw), 1636 (vw), 1457 (s), 1418 (m), 1378 (s), 1276
(vw), 1138 (vs), 1100 (s), 1073 (s), 1048 (vs), 923 (w), 886 (s), 751
(vs), 659 (vs), 569 (vs), 475 (vs). Compound 4 after isolation in
crystalline form is not soluble in most conventional solvents; therefore,
it was not possible to carry out an NMR study.
Synthesis of [Mg2Ti2(μ3-OEt)2(μ-OEt)4(OEt)6(EtOH)4] (1). A
Schlenk flask was charged with Cp2TiCl2 (0.99 g, 3.98 mmol), Mg
turnings (0.21 g, 8.64 mmol), EtOH (25 mL), and toluene (15 mL).
The mixture was vigorously stirred at 65 °C until all metal was
consumed (typically within 18 h). During the reaction course, the
dark-red solution slowly changed to dark green, then navy blue, and
finally light yellow. The resulting solution was filtered off. The filtrate
volume was reduced under a vacuum to 20 mL, and then hexane (20
mL) was slowly added, forming a colorless layer over the solution.
Colorless crystals of 1 were formed at room temperature within a few
days (3−5). The crystals were collected, washed with a mixture of
EtOH and hexane (1:5, 3 × 5 mL), and dried under vacuum. The
resulting filtrate was concentrated to 10 mL and left to produce
another portion of crystalline materials. Overall yield: 1.07 g, 1.23
mmol, 62%. Anal. Calcd for C32H84O16Mg2Ti2: C, 44.21; H, 9.74; Mg,
5.59; Ti, 11.01. Found: C, 44.26; H, 9.76; Mg, 5.62; Ti, 11.03. IR
(cm−1, Nujol mull): 3289 (w), 3119 (w), 2955 (vs), 2922 (vs), 2853
(vs), 2705 (m), 2605 (w), 1462 (vs), 1376 (vs), 1283 (w), 1146 (vs),
Synthesis of [Ca2Zr2(μ4-O)(μ2-OEt)5(OEt)4(EtOH)4Cl]n (5). A
Schlenk flask was charged with Cp2ZrCl2 (1.03 g, 3.52 mmol), metallic
Ca (0.28 g, 6.99 mmol), EtOH (30 mL), and toluene (10 mL). The
mixture was vigorously stirred at 65 °C until all metal was consumed
(typically within 3 h). The resulting light-yellow solution was filtered
off and concentrated under vacuum to 25 mL. After 24 h, colorless
needle crystals of 5 were collected, washed with hexane (3 × 5 mL),
and dried under vacuum. Another portion of crystalline 5 was obtained
after a few days (2−3). Overall yield: 1.20 g, 1.33 mmol, 75%. Calcd
for C26H69O14Cl1Ca2Zr2: C, 34.55; H, 7.69, Cl, 3.92; Ca, 8.87; Zr,
20.18. Found: C, 34.62; H, 7.78, Cl, 4.08; Ca, 8.99; Zr, 20.28. IR
(cm−1, Nujol mull): 3375 (s), 2955 (vs), 2923 (vs), 2854 (vs), 2725
(w), 1636 (vw), 1461 (vs), 1376 (s), 1263 (w), 1153 (m), 1103 (m),
1052 (s), 881 (m), 721 (m), 646 (s), 490 (s). Compound 5 after
isolation in crystalline form is not soluble in most conventional
solvents; therefore, it was not possible to carry out an NMR study.
Synthesis of [Ca2Hf2(μ4-O)(μ2-OEt)5(OEt)4(EtOH)4Cl]n (6). A
Schlenk flask was charged with Cp2HfCl2 (1.01 g, 2.66 mmol), metallic
Ca (0.21 g, 5.24 mmol), EtOH (30 mL), and toluene (10 mL). The
mixture was vigorously stirred at 65 °C until all metal was consumed
(typically within 4 h). The resulting light-yellow solution was filtered
off and concentrated under vacuum to 25 mL. After 2−4 days,
colorless needle crystals of 6 were collected, washed with hexane (3 ×
5 mL), and dried under vacuum. Another portion of crystalline 6 was
obtained after a few days (3−5). Overall yield: 1.12 g, 1.04 mmol, 78%.
Calcd for C26H69O14Cl1Ca2Hf2: C, 28.96; H, 6.45, Cl, 3.29; Ca, 7.43;
Hf, 28.96. Found: C, 28.99; H, 6.56, Cl, 3.28; Ca, 7.59; Hf, 28.98. IR
(cm−1, Nujol mull): 3369 (s), 2955 (vs), 2924 (vs), 2854 (vs), 2725
(w), 1636 (w), 1461 (s), 1378 (s), 1271 (s), 1149 (w), 1091 (m),
1051 (s), 877 (m), 725 (s), 450 (s). Compound 6 after isolation in
crystalline form is not soluble in most conventional solvents; therefore,
it was not possible to carry out an NMR study.
1
1103 (vs), 1058 (vs), 925 (m), 892 (s), 720 (s), 558 (vs). H NMR
(500 MHz, CDCl3, 300 K, ppm): δ [4.48, 4.34, 4.09, 4.02 (m, CH2,
24H)], 3.71 (m, CH2, 8H), [1.31, 1.25 (m, CH3, 48H)]. 13C NMR
(125 MHz, CDCl3, 300 K, ppm): δ 58.2 (CH2, 16C), 18.5 (CH3,
16C).
Synthesis of [Mg2Zr2(μ3-OEt)2(μ-OEt)4(OEt)6(EtOH)4] (2). A
Schlenk flask was charged with Cp2ZrCl2 (0.98 g, 3.35 mmol), Mg
turnings (0.17 g, 6.99 mmol), EtOH (30 mL), and toluene (5 mL).
The mixture was vigorously stirred at 65 °C until all metal was
consumed (typically within 24 h). The resulting yellow solution was
filtered off. The filtrate volume was reduced under a vacuum to 20 mL,
and then hexane (20 mL) was slowly added, forming a colorless layer
over the solution. Colorless crystals of 2 were formed at room
temperature within a few days (1−2). The crystals were collected,
washed with a mixture of EtOH and hexane (1:5, 3 × 5 mL), and dried
under vacuum. The resulting filtrate was concentrated to 10 mL and
left to produce another portion of crystalline materials. Overall yield:
1.12 g, 1.17 mmol, 70%. Anal. Calcd for C32H84O16Mg2Zr2: C, 40.20;
H, 8.86; Mg, 5.08; Zr, 19.08. Found: C, 40.26; H, 8.96; Mg, 4.97; Zr,
19.15. IR (cm−1, Nujol mull): 3145 (m), 2954 (vs), 2924 (vs), 2854
(vs), 2710 (m), 2606 (w), 1459 (s), 1376 (vs), 1282 (w), 1162 (s),
1107 (s), 1063 (vs), 922 (m), 896 (s), 804 (w), 722 (m), 626 (s), 521
1
(vs). H NMR (500 MHz, CDCl3, 300 K, ppm): δ 3.99 (m, CH2,
24H), 3.73 (q, J = 6.3 Hz, CH2, 8H), 2.20 (s, OH, 4H), 1.24 (m, CH3,
48H). 13C NMR (125 MHz, CDCl3, 300 K, ppm): δ 58.3 (CH2, 16C),
20.3, 18.5 (CH3, 16C).
Synthesis of [Mg2Hf2(μ3-OEt)2(μ-OEt)4(OEt)6(EtOH)4] (3). A
Schlenk flask was charged with Cp2HfCl2 (1.00 g, 2.63 mmol), Mg
turnings (0.13 g, 5.35 mmol), EtOH (30 mL), and toluene (10 mL).
The mixture was vigorously stirred at 65 °C until all metal was
Synthesis of [Ca2Ti2(μ3-OEt)2(μ-OEt)4(OEt)6(EtOH)4] (7). A
Schlenk flask was charged with metallic Na (0.43 g, 18.70 mmol),
EtOH (10 mL), and toluene (10 mL). The mixture was vigorously
G
Inorg. Chem. XXXX, XXX, XXX−XXX