Inorganic Chemistry
ARTICLE
stability of these monoamido lanthanide complexes were found
to depends greatly on the Schiff base ligand and the size of the
lanthanide metals. Here we would like to report the results. Their
catalytic activity for addition of amines to carbodiimides is also
included.
solids were crystallized from a mixture of tetrahydrofuran and n-hexane
at room temperature. Complex 6, together with Complex 4 (orange
crystals), was obtained as deep-red crystals after several days. IR (KBr,
cm-1): 2954(s), 2904(m), 2869(m), 1611(s), 1588(s), 1530(m),
1504(w), 1470(s), 1428(s), 1394(w), 1360(w), 1312(w), 1230(s),
1160(s), 1079(w), 835(m), 797(w), 745(w); Anal. Calcd for
C56H69N4O4Nd (1006.39): C, 66.83; H, 6.91; N, 5.57. Found: C,
66.38; H, 7.06; N, 5.99.
’ EXPERIMENTAL SECTION
L02YbN(TMS)2 (9). A solution of the ligand HL0 (1.08 g, 2.75 mmol)
in tetrahydrofuran was slowly added to a stirred solution of Yb[N-
(TMS)2]3 (0.95 g, 1.45 mmol) in tetrahydrofuran over 2 h at -50 °C.
The reaction mixture was stirred for another 2 h. The volatiles were
removed under reduced pressure, and the residues were crystallized
from a mixture of tetrahydrofuran and n-hexane at about 0 °C. The
complex 9 was isolated as light yellow crystals after several days. Yield:
0.61 g (40%). IR (KBr, cm-1): 2961(s), 2870(m), 1622(s), 1584(s),
1536(m), 1465(s), 1438(s), 1393(w), 1363(m), 1324(w), 1246(s),
1162(s), 1108(w), 1044(w), 980(w), 933(w), 862(w), 840(w),
799(w), 762(w), 720(w), 639(m), 555(m), 504(s); Anal. Calcd for
C60H94N3O2Si2Yb (1118.60): C, 64.42; H, 8.47; N, 3.76. Found: C,
64.68; H, 8.26; N, 4.01.
L02YN(TMS)2 (10). The synthesis of complex 10 was carried out in
the same way as that described for complex 9, but HL0 (1.21 g, 3.07
mmol) and Y[N(TMS)2]3 (0.93 g, 1.63 mmol) were used. The light
yellow crystals were isolated. Yield: 0.64 g (41%). 1H NMR (400 MHz,
C6D6): δ 7.96 (d, 2 H), 7.67 (d, 2 H), 7.22-7.17 (m, 4 H), 7.06-7.03
(m, 2 H), 6.81-6.80 (d, 2 H), 3.55-3.44 (m, 2 H), 2.85-2.74 (m, 2 H),
1.63 (d, 6 H), 1.26 (s, 18 H), 1.17 (s, 18 H), 1.16 (d, 6 H), 1.06 (d, 6 H),
0.64 (d, 6 H), 0.41 (s, 18 H); 13C NMR (101 MHz, C6D6): 177.06,
165.28, 165.24, 151.72, 141.68, 141.19, 139.12, 138.19, 133.58, 131.51,
127.11, 125.27, 124.41, 122.93, 35.81, 33.91, 31.57, 31.31, 29.54, 29.21,
23.51, 23.38, 6.56, 6.29; IR (KBr, cm-1): 2961(s), 2870(m), 1623(s),
1584(s), 1536(m), 1463(s), 1435(s), 1395(w), 1362(m), 1324(m),
1250(s), 1161(s), 1107(w), 1044(w), 976(m), 933(m), 840(m),
799(w), 763(m), 720(w), 639(m), 555(m), 505(s); Anal. Calcd for
C60H94N3O2Si2Y (1034.47): C, 69.66; H, 9.16; N, 4.06. Found: C,
69.98; H, 9.06; N, 4.17.
L02NdN(TMS)2 (11). The synthesis of complex 11 was carried out in
the same way as that described for complex 9, but HL0 (1.02 g, 2.58
mmol) and Nd[N(TMS)2]3 (0.85 g, 1.36 mmol) were used. The light
green crystals were isolated. Yield: 0.82 g (58%). IR (KBr, cm-1):
2962(s), 2869(m), 1622(s), 1585(s), 1534(w), 1463(m), 1438(m),
1396(w), 1362(m), 1324(w), 1250(s), 1158(s), 1108(w), 1044(w),
976(w), 933(w), 840(w), 798(w), 761(w), 720(w), 638(m), 555(m),
505(s); Anal. Calcd for C60H94N3O2Si2Nd (1089.80): C, 66.12; H,
8.69; N, 3.86. Found: C, 66.01; H, 8.56; N, 3.77.
L02LaN(TMS)2 (12). The synthesis of complex 12 was carried out in
the same way as that described for complex 9, but HL0 (0.64 g, 1.63
mmol) and La[N(TMS)2]3 (0.53 g, 0.85 mmol) were used. The orange
crystals were isolated. Yield: 0.56 g (63%). 1H NMR (400 MHz, C6D6):
δ 7.89 (s, 2 H), 7.62 (d, 2 H), 7.14-7.09 (m, 4 H), 7.04-7.00 (m, 2 H),
6.81-6.79 (d, 2 H), 3.47-3.36 (m, 2 H), 2.95-2.84 (m, 2 H), 1.62 (d, 6
H), 1.26 (s, 18 H), 1.16 (d, 6 H), 1.15 (s, 18 H), 1.05 (d, 6 H), 0.79 (d, 6
H), 0.34 (s, 18 H); IR (KBr, cm-1): 2961(s), 2870(m), 1622(s),
1584(s), 1540(s), 1462(m), 1437(s), 1397(w), 1362(m), 1325(m),
1253(s), 1162(s), 1107(w), 1043(w), 976(w), 933(w), 841(m),
800(w), 763(w), 720(w), 639(w), 555(m), 505(m); Anal. Calcd for
C60H94N3O2Si2La (1084.47): C, 66.45; H, 8.74; N, 3.88. Found: C,
66.88; H, 9.01; N, 4.14.
Materials and Methods. Standard Schlenk techniques and a
Vacuum Atmospheres N2-filled glovebox were used throughout the
isolation and handling of all metal complexes. Tetrahydrofuran, toluene,
and n-hexane were dried and distilled from sodium benzophenone ketal
under argon prior to use. Ln[N(TMS)2]3 was prepared according to the
literature procedure.11 1H NMR and 13C NMR spectra were recorded
on a 300 MHz or 400 MHz instrument and processed using the NUTS
software. Elemental analyses were performed by direct combustion
using a Carlo-Erba EA 1110 instrument. The IR spectra were recorded
on a Magna-IR 550 spectrometer as KBr pellets. All yields of lanthanide
complexes were calculated based on ligands and were of crystallized yield
only for the first time.
L2EuN(TMS)2 THF C6H14 (3). A solution of the Eu[N(TMS)2]3
3
3
(1.19 g, 1.88 mmol) in n-hexane was added as fast as possible in one
portion to a stirring slurry of ligand HL (1.22 g, 3.38 mmol) in n-hexane
at room temperature. The reaction mixture was stirred for 2 h. The
volatiles were removed under reduced pressure, and the residue was
extracted with about 5 mL of n-hexane; removing the n-hexane solution
by centrifugation led to orange solids. The solids were crystallized from
toluene or a mixture of tetrahydrofuran and n-hexane at 0 °C. Complex 3
was isolated as orange crystals after several days. Yield: 0.91 g (45%). IR
(KBr, cm-1): 2956(s), 2904(m), 2869(m), 1610(s), 1600(s), 1531(s),
1502(s), 1463(m), 1425(s), 1383(m), 1360(w), 1314(w), 1254(s),
1233(m), 1161(s), 1085(w), 1064(w), 931(m), 840(m), 793(m),
755(w), 744(w); Anal. Calcd for C64H94N5O3Si2Eu (1189.58): C,
64.61; H, 7.97; N, 5.89. Found: C, 63.82; H, 7.02; N, 5.99.
L2NdN(TMS)2 0.5THF (4). The synthesis of complex 4 was carried
3
out in the same way as that described for complex 3, but HL (1.23 g, 3.40
mmol) and Nd[N(TMS)2]3 (1.18 g, 1.89 mmol) were used. The orange
crystals were isolated. Yield: 1.01 g (56%). IR (KBr, cm-1): 2954(s),
2903(m), 2869(m), 1609(s), 1599(s), 1528(s), 1501(s), 1462(m),
1424(s), 1382(m), 1359(w), 1314(w), 1250(s), 1231(s), 1159(s),
1084(w), 1063(w), 932(m), 839(m), 792(m), 754(w), 744(w); Anal.
Calcd for C56H76N5O2.5Si2Nd (1059.64): C, 63.47; H, 7.23; N, 6.61.
Found: C, 63.17; H, 6.87; N, 5.83.
L2LaN(TMS)2 0.5THF (5). The synthesis of complex 5 was carried
3
out in the same way as that described for complex 3, but HL (2.12 g, 6.10
mmol) and La[N(TMS)2]3 (2.10 g, 3.39 mmol) were used. The orange
crystals were isolated. Yield: 2.02 g (63%). 1H NMR (400 MHz, C6D6):
δ 9.28 (br, 2 H), 8.30 (s, 2 H), 7.60 (s, 2 H), 7.55-7.40 (m, 2 H), 7.23 (s,
2 H), 7.16-7.11 (m, 4 H, over lapping), 7.01-6.98 (m, 2 H), 6.78 (br, 2
H), 1.37 and 1.30 (s and br, 36 H), -0.03 (s, 18 H); 13C NMR (101
MHz, C6D6): 168.90, 167.08, 151.50, 150.68, 144.12, 140.04, 137.81,
135.77, 129.46, 128.41, 128.18, 128.14, 127.94, 124.89, 122.92, 121.48,
118.63, 35.41, 34.10, 31.78, 30.06, 5.38; IR (KBr, cm-1): 2955(s),
2904(m), 2871(m), 1611(s), 1599(s), 1531(s), 1502(s), 1461(m),
1426(s), 1382(m), 1360(w), 1314(w), 1251(s), 1232(s), 1160(s),
1084(w), 1065(m), 932(m), 838(m), 793(m), 754(w), 744(w); Anal.
Calcd for C56H76N5O2.5Si2La (1054.31): C, 63.79; H, 7.27; N, 6.64.
Found: C, 64.61; H, 7.12; N, 5.60.
L[N, O, O]3-Nd(THF) THF (6). The complex 4 (0.59 g, 0.56 mmol)
3
L002YbN(TMS)2 (13). The synthesis of complex 13 was carried out in
the same way as that described for complex 9, but HL00 (0.87 g, 2.58
mmol) and Yb[N(TMS)2]3 (0.89 g, 1.36 mmol) were used. The orange
crystals were isolated. Yield: 0.71 g (55%). IR (KBr, cm-1): 2957(s),
2870(m), 1623(s), 1586(s), 1537(s), 1467(m), 1435(s), 1393(w),
was dissolved in about 10 mL of tetrahydrofuran (THF) and sealed in
the reaction bottle, then heated in the reaction system to 70 °C. And the
color of the solution changed from orange to deep-red gradually. After 5
days, the volatiles were removed under reduced pressure, and the
residues were washed with about 10 mL of n-hexane at 3 times. The
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dx.doi.org/10.1021/ic102529d |Inorg. Chem. 2011, 50, 2634–2643