C.T. Carver, P.L. Diaconescu / Journal of Alloys and Compounds 488 (2009) 518–523
519
or NC5H4), 6.80 (m, 1H, NC5H5 or NC5H4), 6.71 (m, 2H, NC5H5), 4.19 (bs, 4H, fc-
2.6. X-ray crystal structures
CH), 3.62 (bs, 4H, fc-CH), 0.84 (s, 18H, SiC(CH3)3), −0.16 (s, 12H, Si(CH3)2). 13 C NMR
(126 MHz, C6D6): ␦, ppm: 144.1, 134.1, 130.4, 122.3, 104.6, 67.6, 27.7, 20.6, −3.0. Anal.
for C32H47 FeN4Si2Sc. Calcd.: C, 59.61%; H, 7.35%; N, 8.69%. Found: C, 59.65%; H, 7.51%;
N, 8.51%.
X-ray quality crystals were obtained from various concentrated solutions placed
in a −35 ◦C freezer in the glove box. Inside the glove box, the crystals were coated
with oil (STP Oil Treatment) on a microscope slide, which was brought outside
the glove box. The X-ray data collections were carried out on a Bruker AXS single
crystal X-ray diffractometer using Mo K␣ radiation and a SMART APEX CCD detec-
tor. The data was reduced by SAINTPLUS and an empirical absorption correction
was applied using the package SADABS. The structures were solved and refined
using SHELXTL (Brucker 1998, SMART, SAINT, XPREP AND SHELXTL, Brucker AXS
Inc., Madison, Wiscosin, USA). All atoms were refined anisotropically and hydrogen
atoms were placed in calculated positions unless specified otherwise. Tables with
atomic coordinates and equivalent isotropic displacement parameters, with all the
bond lengths and angles, and with anisotropic displacement parameters are listed
in the cif files.
2.2. Reaction of Sc(fc[NSitBuMe2]2)(ꢀ2-N,C-pyridyl)(py), 2-py, with ethylene
2-py (15 mg, 0.0232 mmol) was dissolved in C6D6 (1.5 mL); this solution was
placed in a J-Young tube and 10 psi of ethylene was introduced. The reaction mixture
was allowed to stand at room temperature and monitored by 1H NMR spectroscopy.
The reaction is complete in 4 h and quantitative. Alternately, the insertion product
can be formed directly from 1CH Ar-THF and pyridine under an atmosphere of ethy-
2
lene. In a 50-mL Schlenk tube, 1CH Ar-THF (200 mg, 0.295 mmol) was combined with
2
2 equiv of pyridine (46.6 mg, 0.589 mmol) in toluene (8 mL) and ethylene (10 psi)
was introduced. The reaction mixture was stirred at 70 ◦C for 18 h. The solvent
was removed and the resulting yellow solid was extracted in hexanes and filtered
through Celite. Yield 167 mg, 84.3%, as 2 crops from hexanes. 1H NMR (300 MHz,
C6D6): ␦, ppm: 9.30 (bs, 2H, NC5H5), 8.59 (d, 1H, NC5H5 or NC5H4), 6.98 (tr, 1H,
NC5H5 or NC5H4), 6.89 (tr, 1H, NC5H5 or NC5H4), 6.85 (d, 1H, NC5H5 or NC5H4),
6.70 (tr, 2H, NC5H5), 6.60 (tr, 1H, NC5H5 or NC5H4), 4.15 (bs, 2H, fc-CH), 3.93 (bs,
2H, fc-CH), 3.77 (t, 2H, ScCH2CH2Py), 3.60 (bs, 2H, fc-CH), 2.99 (bs, 2H, fc-CH), 0.99
(s, 18H, SiC(CH3)3), 0.93 (t, 2H, ScCH2CH2Py), 0.35 and 0.01 (s, 12H, Si(CH3)2). 13 C
NMR (126 MHz, C6D6): ␦, ppm: 172.9, 150.9, 147.0, 137.9, 124.1, 123.9, 119.9, 102.0,
2.6.1. 2-py
X-ray quality crystals were obtained from a concentrated toluene:pentane
solution placed in a −35 ◦C freezer in the glove box. A total of 14784 reflec-
tions (−13 ≤ h ≤ 13, −14 ≤ k ≤ 14, −20 ≤ l ≤ 20) were collected at T = 110(2) K with
2ꢁmax = 56.39◦, of which 7992 were unique (Rint = 0.0203). The residual peak and hole
electron density were 1.34 and −0.78 eA−3. The least-squares refinement converged
normally with residuals of R1 = 0.0423 and GOF = 1.035. Crystal and refinement data
for 2-py: formula C32H47 N4Si2ScFe, space group P1¯ , a = 10.4265(11), b = 10.7864(11),
c = 15.3460(16), ˛ = 88.151(2), ˇ = 84.251(1), ꢂ = 75.721(2)◦, V = 1664.1(3) Å3, Z = 2,
ꢃ = 0.739 mm−1, F(0 0 0) = 684, R1 = 0.00547 and wR2 = 0.1138 (based on all 7992 data,
I > 2ꢄ(I)).
71.1, 67.9, 67.3, 66.8, 66.0, 28.0, 25.2, 20.8, −2.0. Anal. for C34
H51 FeN4Si2Sc. Calcd.: C,
60.70%; H, 7.64%; N, 8.33%. Found: C, 60.70%; H, 7.95%; N, 8.23%.
2.3. Reaction of Sc(fc[NSitBuMe2]2)(ꢀ2-N,C-6-Ph-pyridyl)(py), 2-pyPh, with
ethylene
2.6.2. 3-pyPh
2-pyPh (100 mg, 0.140 mmol) was dissolved in toluene (10 mL) and placed in a
100-mL Schlenk tube. Ethylene (0.680 atm) was introduced. The reaction mixture
was allowed to stir for 3 h at room temperature. The solvent was removed and the
resulting yellow solid was extracted in hexanes and filtered through Celite. Yield
78.3 mg, 83.4%. 1H NMR (500 MHz, C6D6): ␦, ppm: 7.79 (d, 2H, C6H5), 7.20 (t, 2H,
C6H5), 7.09 (t, 1H, NC5H3 or C6H5), 7.04 (t, 1H, NC5H3 or C6H5), 6.88 (d, 1H, NC5H3
or C6H5), 6.78 (d, 1H, NC5H3 or C6H5), 4.21 (s, 2H, fc-CH), 3.88 (s, 2H, fc-CH), 3.78 (t,
2H, ScCH2CH2Py), 3.61 (s, 2H, fc-CH), 3.18 (s, 2H, fc-CH), 0.93 (t, 2H, ScCH2CH2Py),
0.93 (s, 18H, SiC(CH3)3), 0.02 and −0.15 (s, 12H, Si(CH3)2). 13 C NMR (126 MHz, C6D6):
␦, ppm: 173.2, 158.4, 140.1, 138.7, 130.0, 127.2, 123.5, 120.6, 106.7, 70.0, 68.4, 67.1,
66.6, 36.6, 27.8, 20.4, −3.2, −3.4. Anal. C35H50FeN3Si2Sc. Calcd.: C, 62.77%; H, 7.52%;
N, 6.27%. Found: C, 62.72%; H, 7.87%; N, 6.25%.
X-ray quality crystals were obtained from a concentrated toluene: pentane
solution placed in a −35 ◦C freezer in the glove box. The data were not very
good and only connectivity information could be obtained. Only cell parame-
ters will be included. A total of 34831 reflections (−46 ≤ h ≤ 46, −21 ≤ k ≤ 21,
−19 ≤ l ≤ 19) were collected at T = 100(2) K with 2ꢁmax = 60.94◦, of which 10233
were unique. Crystal data for 3-pyPh: formula C35H50N3Si2ScFe, space group C2/c,
a = 32.9742, b = 15.5417, c = 13.8670, ˇ = 95.891◦, V = 7068.96 Å3, Z = 8, ꢃ = 0.70 mm−1
,
F(0 0 0) = 2848.
2.6.3. 5-pyPh
X-ray quality crystals were obtained from a concentrated toluene: pentane solu-
tion placed in a −35 ◦C freezer in the glove box. A molecule of toluene was found.
The toluene molecule is sitting on a special position and is disordered such that
one of the aromatic carbon atoms is also the methyl group of the other half of
the molecule. The occupancy for this carbon atom was fixed to 75% and of three
other carbons to 50%. One of the solvent atoms was not refined anisotropically;
also hydrogen atoms were not added to the solvent carbon atoms. The allyl group
(C2 and C3 atoms) is disordered over two positions. This disorder was model such
that each position is occupied 50%. The two components of C2 (C2a and C2b)
were not refined anisotropically. This atom (C2) is thermally disordered, account-
ing for the high electron density found next to it. The disorder was not refined. A
total of 34875 reflections (−13 ≤ h ≤ 13, −21 ≤ k ≤ 21, −30 ≤ l ≤ 30) were collected
at T = 100(2) K with 2ꢁmax = 56.66◦, of which 9535 were unique (Rint = 0.0904). The
residual peak and hole electron density were 2.20 and −0.90 eA−3. The least-squares
refinement converged normally with residuals of R1 = 0.0593 and GOF = 1.032.
Crystal and refinement data for 5-pyPh: formula C40.25H52N3Si2ScFe, space group
P2(1)/c, a = 10.376(3), b = 16.437(5), c = 22.721(7), ˇ = 93.281(3)◦, V = 3868.7(19) Å3,
Z = 4, ꢃ = 0.644 mm−1, F(0 0 0) = 1558, R1 = 0.1111 and wR2 = 0.1568 (based on all 9535
data, I > 2ꢄ(I)).
2.4. Reaction of Sc(fc[NSitBuMe2]2)(ꢀ2-N,C-6-Ph-pyridyl)(py), 2-pyPh, with
2-butyne
2-pyPh (200 mg, 0.280 mmol) was placed in a J-Young tube with 2-butyne (76 mg,
1.40 mmol) in C6D6. The reaction mixture was heated for 48 h at 50 ◦C. The volatiles
were removed and the resulting brownish-yellow solid was washed with 1.5 mL
hexanes, giving a yellow solid. Yield 152 mg, 70.6%. 1H NMR (500 MHz, C6D6): ␦,
ppm: 7.78 (d, 2H, C6H5), 7.20 (m, 4H, C6H5 and NC5H4), 7.05 (m, 1H, NC5H4), 7.01
(m, 1H, NC5H4), 6.74 (d, 1H, NC5H4), 4.18 (s, 2H, fc-CH), 3.99 (s, 2H, fc-CH), 3.54
(s, 2H, fc-CH), 3.04 (s, 2H, fc-CH), 2.29 (s, 3H, CH3-CC), 1.98 (s, 3H, CH3-CC), 0.91
(s, 18H SiC(CH3)3), 0.04 and −0.10 (s, 12H, Si(CH3)2). 13 C NMR (126 MHz, C6D6): ␦,
ppm: 167.2, 158.0, 141.3, 139.4, 135.2, 131.1, 129.8, 126.5, 118.7, 118.3, 104.3, 69.2,
68.4, 67.6, 67.2, 27.7, 22.1, 20.2, 12.3, −2.9, −3.9. Anal. for C37H52FeN3Si2Sc. Calcd.: C,
63.87%; H, 7.53%; N, 6.04%. Found: C, 63.63%; H, 7.87%; N, 6.25%.
2.5. Reaction of Sc(fc[NSitBuMe2]2)(ꢀ2-N,C-6-Ph-pyridyl)(py), 2-pyPh, with
1,3-butadiene
2-pyPh (200 mg, 0.280 mmol) was dissolved in toluene (10 mL) and placed in
a 100-mL Schlenk tube. Butadiene was introduced (ca. 3 atm). The reaction was
stirred overnight at room temperature. The volatiles were removed and the product
was washed with 1.5 mL hexanes. Yield 148 mg, 75.9%. 1H NMR (300 MHz, C6D6): ␦,
ppm: 7.69 (d, 2H, C6H5), 7.24 (t, 2H, C6H5 and/or NC5H4), 7.09 (m, 1H, C6H5 and/or
NC5H4), 6.92 (m, 1H, C6H5 and/or NC5H4), 6.84 (td, 1H, CH2CHCHCH2), 6.65 (m,
2H, C6H5 and/or NC5H4), 4.37 (m, 1H, CH2CHCHCH2), 4.24 (s, 1H, CH2CHCHCH2),
4.18 (s, 1H, CH2CHCHCH2), 3.89 and 3.49 (m, 8H, fc-CH), 3.10 (s, 1H, CH2CHCHCH2),
2.63 (s, 1H, CH2CHCHCH2), 1.00 and 0.92 (s, 18H SiC(CH3)3), −0.02, −0.03, −0.18, and
−0.22 (s, 12H, Si(CH3)2). 13 C NMR (126 MHz, C6D6): ␦, ppm: 174.5, 160.8, 149.0, 140.2,
138.7, 129.4, 129.3, 128.9, 128.4, 124.0, 122.5, 103.7, 103.6, 89.5, 73.2, 70.4, 69.7, 69.5,
69.4, 69.0, 67.6, 65.9, 65.8, 40.9, 28.1, 28.0, 21.2, 20.7, −2.8, −3.2, −3.3, −3.6. Anal.
for C37H52FeN3Si2Sc·0.5 toluene (consistent with X-ray crystal structure). Calcd.: C,
65.57%; H, 7.61%; N, 5.66%. Found: C, 65.15%; H, 7.67%; N, 5.68%.
3. Results and discussion
Although the reaction between the ferrocene 1,1ꢀ-diamide
scandium benzyl complex, Sc(fc[NSitBuMe2]2)(CH2Xy-3,5)(THF)
(1CH Ar-THF, Xy = xylyl) [26] and pyridine or 2-picoline gave
2
mixtures of compounds, employing Sc(fc[NSitBuMe2]2)Me(THF)2
(1Me-THF) [26] allowed the isolation of an 2(N,C)-pyridyl complex,
Sc(fc[NSitBuMe2]2)(2-N,C-pyridyl)(py) (2-py, Eq. (1)). Complex 2-
py was characterized by X-ray crystallography, which shows the
pyridyl and pyridine ligands coplanar and coordinated in a plane
perpendicular to the Namide–Fe–Namide one (Fig. 1).