Synthesis and Analysis of a Scandium Dinitrogen Complex
A R T I C L E S
Table 1. X-ray Data Collection Parameters for (C5Me4H)2ScCl(THF), 1, (C5Me4H)2Sc(η3-C3H5), 2, [(C5Me4H)2Sc][(µ-Ph)BPh3], 3,
[(C5Me4H)2Sc]2(µ-η2:η2-N2), 4, and {[(C5Me4H)2Sc]2(µ-η2:η2-N2)[(C5Me4H)2Sc]2(µ-O)}, 5
complex
1
2
3
4
5
empirical formula
fw
temp (K)
crystal system
space group
a (Å)
C22H34ClOSc
394.90
153(2)
monoclinic
P21/n
8.6644(5)
14.8610(9)
16.4746(10)
90
97.4774(7)
90
2103.3(2)
4
1.247
0.484
C21H31Sc
328.42
153(2)
monoclinic
P21/n
8.7813(8)
14.7244(13)
14.1177(13)
90
92.186(2)
90
1824.1(3)
4
1.196
0.399
0.0282
0.0798
C42H46BSc
606.56
163(2)
C36H52N2Sc2
602.72
98(2)
monoclinic
P21/n
8.4928(9)
10.1010(10)
18.4580(18)
90
90.3390(10)
90
1583.4(3)
2
1.264
0.455
[C36H52N2Sc2][C36H52OSc2]
1193.41
148(2)
monoclinic
Pn
8.8370(14)
21.042(3)
17.909(3)
90
91.485(2)
90
3329.1(9)
2
triclinic
j
P1
11.8363(13)
11.9868(13)
12.4080(13)
100.450(2)
98.128(2)
100.555(2)
1674.0(3)
2
1.203
0.248
0.0517
0.1239
b (Å)
c (Å)
R (deg)
ꢀ (deg)
γ (deg)
volume (Å3)
Z
Fcalcd (Mg/m3)
1.191
0.433
0.0675
0.1647
µ (mm-1
)
R1 [I > 2.0σ(I)]a
wR2 (all data)a
0.0333
0.0913
0.0327
0.0885
a
2
2
Definitions: wR2 ) [∑[w(Fo - Fc2)2]/∑[w(Fo )2]]1/2, R1 ) ∑||Fo| - |Fc||/∑|Fo|.
1H, CH2CHCH2), 5.93 (s, ∆ν1/2 ) 9 Hz, 2H, C5Me4H), 3.81 (s,
∆ν1/2 ) 102 Hz, 2H, allyl anti CH2), 1.95 (s, 12H, C5Me4H), 1.64
(s, ∆ν1/2 ) 12 Hz, 12H, C5Me4H). 13C NMR (126 MHz, benzene-
d6): δ 157.3 (CH2CHCH2), 121.2 (C5Me4H), 116.6 (C5Me4H), 112.6
(C5Me4H), 70.6 (CH2CHCH2), 13.4 (C5Me4H), 12.3 (C5Me4H). 1H
NMR (500 MHz, toluene-d8): δ 7.0 (m, 1H, CH2CHCH2), 5.88 (s,
∆ν1/2 ) 9 Hz, 2H, C5Me4H), 3.70 (s, ∆ν1/2 ) 98 Hz, 2H, allyl anti
CH2), 1.93 (d, 12H, C5Me4H), 1.62 (s, ∆ν1/2 ) 12 Hz, 12H,
C5Me4H). 1H NMR (500 MHz, toluene-d8, 228 K): δ 7.06 (m, 1H,
CH2CHCH2), 6.07 (s, 1H, C5Me4H), 5.73 (s, 1H, C5Me4H), 3.82
(d, 2H, allyl anti CH2), 2.07 (d, 2H, allyl syn CH2), 1.96 (d, 12H,
grown from a concentrated toluene solution at -35 °C over the
course of 48 h. Isolation of the solvated analogue of 3,
[(C5Me4H)2Sc(THF)2][BPh4], is given in the Supporting Informa-
tion.
[(C5Me4H)2Sc]2(µ-η2:η2-N2), 4. In a nitrogen-filled glovebox,
KC8 (0.032 g, 0.25 mmol) was added to a stirred solution of 3
(0.150 g, 0.25 mmol) in 5 mL of THF. After the reaction mixture
was stirred for 20 min, black and white insoluble materials
(presumably graphite and KBPh4) were removed by centrifugation
and filtration. The green filtrate was stored at -35 °C for 4 d to
afford 4 as a dark red microcrystalline solid (22 mg, 30%). Red
crystals of 4 suitable for X-ray analysis were obtained in an NMR
tube from a concentrated benzene-d6 solution at 25 °C over the
1
C5Me4H), 1.79 (s, 6H, C5Me4H), 1.42 (s, 6H, C5Me4H). H NMR
(500 MHz, toluene-d8, 373 K): δ 7.01 (m, 1H, CH2CHCH2), 5.85
(s, 2H, C5Me4H), 2.84 (d, ∆ν1/2 ) 25.7 Hz, 4H, allyl CH2), 1.92
(s, 12H, C5Me4H), 1.64 (s, 12H, C5Me4H). 13C NMR (126 MHz,
toluene-d8): δ 157.1 (CH2CHCH2), 120.8 (C5Me4H), 116.2
(C5Me4H), 112.3 (C5Me4H), 70.2 (CH2CHCH2), 13.0 (C5Me4H),
11.9 (C5Me4H). 45Sc NMR (145 MHz, benzene-d6): δ 153 (∆ν1/2
) 350 Hz). IR: 3078w, 3062w, 2963m, 2909s, 2860s, 2726w,
1663w, 1555w, 1485m, 1435m, 1382m, 1329w, 1253w, 1176w,
1147w, 1028m, 974w, 834m, 794vs, 702s, 614w, 594w cm-1. Anal.
Calcd for C21H31Sc: C, 76.80; H, 9.51; Sc, 13.69. Found: C, 76.60;
H, 9.45; Sc, 14.02.
1
course of 6 d. H NMR (500 MHz, benzene-d6): δ 6.01 (s, 4H,
C5Me4H), 2.01 (s, 24H, C5Me4H), 2.00 (s, 24H, C5Me4H). 13C NMR
(126 MHz, benzene-d6): δ 119.8 (C5Me4H), 118.4 (C5Me4H), 114.5
(C5Me4H), 12.6 (C5Me4H), 11.9 (C5Me4H). 15N NMR (61 MHz,
benzene-d6, referenced to MeNO2): δ 385. 45Sc NMR (145 MHz,
benzene-d6): δ 143 (∆ν1/2 ) 2700 Hz). IR: 2971m, 2908s, 2861s,
2724w, 1746w, 1641w, 1485w, 1444m, 1383m, 1370m, 1332w,
1149w, 1110w, 1020w, 973w, 825vs, 773m, 700w, 619m cm-1
.
UV-vis (benzene, nm (ꢀ)): 592 (60), 447 sh (200). Anal. Calcd
for C36H52N2Sc2: C, 71.74; H, 8.70; N, 4.65. Found: C, 71.33; H,
9.15; N, 4.37.
[(C5Me4H)2Sc][(µ-Ph)BPh3], 3. In an argon-filled glovebox free
of coordinating solvents, [HNEt3][BPh4] (0.185 g, 0.435 mmol) was
added to a stirred yellow solution of 2 (0.119 g, 0.362 mmol) in
20 mL of toluene. After the mixture was stirred for 3 h, the yellow
solution was filtered to remove insoluble yellow-white material.
Evaporation of the solution yielded an oily product that crystallized
after at least 2 h under vacuum (10-3 Torr). The thoroughly dried
material was washed with hexane to give a yellow crystalline solid.
The hexane washing cycle of this yellow crystalline material was
repeated until the supernatant was colorless. This yielded 3 as a
X-ray Crystallographic Data. Information on X-ray data
collection, structure determination, and refinement for 1-5 is given
in Table 1. Details are given in the Supporting Information.
Computational Details. The structure of 4 was initially opti-
mized using the TPSSH20 hybrid meta-GGA functional and split
valence basis sets with polarization functions on non-hydrogen
atoms (SV(P)).21 TPSSH was chosen due to its established
performance for transition metal22,23 and lanthanide compounds.24
Fine quadrature grids (size m4)25 were used throughout except for
the final TZVP optimization. Vibrational frequencies were computed
at the TPSSH/SV(P) level26 and scaled by a factor of 0.95 to
1
yellow crystalline powder (0.165 g, 75%). H NMR (500 MHz,
benzene-d6): δ 8.02 (m, 8H, C6H5), 7.21 (m, 8H, C6H5), 7.12 (m,
4H, C6H5), 5.17 (s, 2H, C5Me4H), 1.49 (s, 12H, C5Me4H), 1.35 (s,
12H, C5Me4H). 13C NMR (126 MHz, benzene-d6): δ 136.2 (C6H5),
134.1 (C6H5), 131.9 (C5Me4H), 128.9 (C5Me4H), 128.8 (C6H5),
127.7 (C6H5), 125.7 (C6H5), 124.2 (C6H5), 120.4 (C5Me4H), 13.5
(C5Me4H), 12.2 (C5Me4H). 45Sc NMR (145 MHz, benzene-d6): δ
190 (∆ν1/2 ) 7800 Hz). IR: 3122w, 3088w, 3051m, 3040m, 2997m,
2983m, 2911m, 2861m, 2732w, 1933w, 1873w, 1807w, 1759w,
1581m, 1568m, 1479s, 1426s, 1385s, 1376m, 1328w, 1286w,
1267w, 1240m, 1184m, 1157m, 1150m, 1066m, 1031m, 1022s,
978w, 910w, 895m, 837s, 824s, 764m, 744vs, 730vs, 705vs, 624m,
605vs cm-1. Anal. Calcd for C42H46BSc: C, 83.16; H, 7.64. Found:
C, 83.00; H, 7.79. Single crystals suitable for X-ray analysis were
(20) Staroverov, V. N.; Scuseria, G. E.; Tao, J.; Perdew, J. P. J. Chem.
Phys. 2003, 119, 12129–12137.
(21) Scha¨fer, A.; Horn, H.; Ahlrichs, R. J. Chem. Phys. 1992, 97, 2571–
2577.
(22) Furche, F.; Perdew, J. P. J. Chem. Phys. 2006, 124, 044103-27.
(23) Waller, M. P.; Braun, H.; Hojdis, N.; Bu¨hl, M. J. Chem. Theory
Comput. 2007, 3, 2234–2242.
(24) Evans, W. J.; Fang, M.; Zucchi, G.; Furche, F.; Ziller, J. W.; Hoekstra,
R. M.; Zink, J. I. J. Am. Chem. Soc. 2009, 131, 11195–11202.
(25) Treutler, O.; Ahlrichs, R. J. Chem. Phys. 1995, 102, 346–354.
(26) Deglmann, P.; Furche, F.; Ahlrichs, R. Chem. Phys. Lett. 2002, 362,
511–518.
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