300 Inorganic Chemistry, Vol. 38, No. 2, 1999
Silverman et al.
over Celite. The volume of the resulting yellow solution was reduced
by half and stored at -20 °C. After a few days, yellow crystals of
X-ray quality were obtained (2.0 g, 89%). Mp: 155-157 °C. HRMS:
calcd for C54H90InN3, 895.617; found, 895.617. 1H NMR (300.15 MHz,
C6D6): δ 1.38 (s, 27 H, p-(CH3)3C), 1.43 (s, 54 H, o-(CH3)3C), 3.98
(s, 3 H, NH), 7.32 (s, 6 H, C6H2). 13C NMR (300.15 MHz, C6D6): δ
30.41 (s, o-(CH3)3C), 32.16 (s, o-(CH3)3C), 34.60 (s, p-(CH3)3C), 36.29
(s, p-(CH3)3C), 139.99 (s, p-C6H2), 141.21 (s, m-C6H2), 149.29 (s,
o-C6H2). Anal. Calcd for C54H90InN3: C, 72.40; H, 10.06; N, 4.69.
Found: C, 68.78; H, 9.86; N, 4.45.
half. After 2 days storage at -20 °C, yellow crystals of X-ray quality
were obtained (2.8 g, 67%). Mp: 96 °C (dec), 145-146 °C. 1H NMR
(300.15 MHz, CD2Cl2): δ 1.00 (d, 36 H, (CH3)2CH, J ) 6.6 Hz), 2.72
(m, 6 H, (CH3)2CH, J ) 6.6 Hz), 3.12 (s, 3 H, NH), 6.68 (t, 3 H,
p-C6H3, J ) 7.6 Hz), 6.92 (d, 6 H, m-C6H3, J ) 7.6 Hz), 7.42 (m,
C5H5N), 7.84 (m, C5H5N), 8.68 (m, C5H5N). 13C NMR (300.15 MHz,
CD2Cl2): 23.40 (s, (CH3)2CH), 28.93 (s, (CH3)2CH), 123.08 (s,
m-C6H3), 125.26 (s, C5H5N), 137.37 (s, p-C6H3 and C5H5N), δ 149.59
(s, C5H5N). Anal. Calcd for C46H64InN5: C, 68.91; H, 7.99; N, 8.74.
Found: C, 66.20; H, 8.47; N, 7.97.
Synthesis of [Al{N(H)Dipp}3(py)] (7). 2,6-Diisopropylaniline (1.6
mL, 1.5 g, 8.8 mmol) was added dropwise over a 5 min period to a
stirred solution of [Al(NMe2)3]2 (0.46 g, 2.9 mmol) in hexane (30 mL)
at 25 °C. Pyridine (ca. 5 mL) was added, yielding a bright yellow
solution that was stirred for 14 h. The solvent was removed in vacuo
resulting in a yellow oil. The oil was redissolved in pyridine (15 mL)
and stored at -20 °C. After a few days, yellow crystals of 7 were
obtained but were not of X-ray quality (1.4 g, 78%). Mp: 156-160
°C. HRMS: calcd mass for C41H59AlN4, 635.463; found, 635.464. 1H
NMR (300.15 MHz, CD2Cl2): δ 1.00 (d, 36 H, (CH3)2CH, J ) 6.0
Hz), 2.89 (s, 3 H, NH), 3.03 (m, 6 H, (CH3)2CH, J ) 6.0 Hz), 6.69 (t,
3 H, p-C6H3, J ) 7.5 Hz), 6.92 (d, 6 H, m-C6H3, J ) 7.5 Hz), 7.65 (m,
C5H5N), 8.11 (m, C5H5N), 8.90 (m, C5H5N). 13C NMR (300.15 MHz,
C6D6): δ 23.71(s, (CH3)2CH), 28.93 (s, (CH3)2CH), 123.14 (s, m-C6H3),
123.30 (s, C5H5N), 132.93 (s, m-C6H3), 138.22 (s, p-C6H3 and C5H5N),
146.43 (s, C5H5N). Anal. Calcd for C41H59AlN4: C, 77.60; H, 9.31; N,
8.83. Found: C, 73.27; H, 9.30; N, 8.24.
Synthesis of [Ga{N(H)Dipp}3(py)] (8). 2,6-Diisopropylaniline (2.5
mL, 2.4 g, 13 mmol) was added dropwise over a 5 min period to a
stirred solution of [Ga(NMe2)3]2 (0.51 g, 2.5 mmol) in pyridine (30
mL) at 25 °C and stirred for a further 14 h. The solvent was removed
in vacuo, resulting in a brown oil which was stored at 25 °C. After 24
h, yellow crystals of X-ray quality were obtained (1.1 g, 62%). Mp:
108-110 °C. HRMS: calcd for C41H59GaN4, 677.639; found, 677.641.
1H NMR (300.15 MHz, CD2Cl2): δ 0.96 (d, 36 H, (CH3)2CH, J ) 6.6
Hz), 2.68-2.74 (m, 6 H, (CH3)2CH, J ) 6.7 Hz), 2.92 (s, 3 H, NH),
6.70 (t, 3 H, p-C6H3, J ) 7.8 Hz), 6.91 (d, 6 H, m-C6H3, J ) 7.5 Hz),
7.64 (m, C5H5N), 8.12 (m, C5H5N), 9.01 (m, C5H5N). 13C NMR (300.15
MHz, CD2Cl2): δ 23.97 (s, (CH3)2CH), 28.33 (s, (CH3)2CH), 119.01
(s, m-C6H3), 122.95 (s, C5H5N), 138.53 (s, p-C6H3 and C5H5N), 146.69
(s, C5H5N). Anal. Calcd for C41H59GaN4: C, 72.67; H, 8.78; N, 8.27.
Found: C, 72.44; H, 8.85; N, 7.87.
X-ray Crystallography. Crystallographic data and details of the data
collection procedures and structure refinement for 3, 8, and 9 are
presented in Table 2. Crystals of 3 and 9 were grown from Et2O solution
at -20 °C, while those of 8 were grown from pyridine solution at -25
°C. Crystals of 3 were mounted on glass fibers, whereas crystals of 8
and 9 were mounted in thin-walled glass capillaries and sealed under
argon. The data set for compound 3 was collected on a Siemens P4
diffractometer at -100 °C, and those for 8 and 9 were collected on an
Enraf Nonius CAD4 diffractometer at 25 °C. Graphite-monochromated
Mo KR radiation (λ ) 0.710 73 Å) was used in each case. Accurate
unit cell parameters were determined by recentering 25 optimal high-
angle reflections. Three standard reflections were measured every 1800
s during data collection, and no decreases in intensities were observed.
Corrections were applied for Lorentz-polarization and absorption
effects. The structures were solved for the heavy atoms by direct
methods. Subsequent difference syntheses gave all other non-hydrogen
atomic positions and these were refined by full-matrix least-squares
on F2 using the Siemens SHELXL PLUS 5.0 (PC) software package.19
All non-hydrogen atoms were allowed anisotropic thermal motion. The
hydrogen atoms were included at calculated positions (C-H, 0.96 Å)
and were refined using a riding model and a general isotropic thermal
parameter.
Acknowledgment. We are grateful to the Science and
Technology Center Program of the National Science Foundation
(CHE-08920120), the National Science Foundation (CHE-
9629088), and the Robert A. Welch Foundation for generous
financial support.
Note Added in Proof. While the present work was in press,
a paper appeared describing the synthesis and structure of
In(NPh2)3(py): Kim, J.; Bott, S. G.; Hoffman, D. M. Inorg.
Chem. 1998, 37, 3835.
Synthesis of [In{N(H)Dipp}3(py)2] (9). n-Butyllithium (11 mL, 1.6
M solution in hexane) was added dropwise to a stirred solution of
DippNH2 (3.3 mL, 3.1 g, 18 mmol) in pentane (25 mL) at -78 °C,
and the stirred reaction mixture was allowed to warm to 25 °C
overnight. The pentane was removed, and the resulting white solid was
dissolved in diethyl ether (30 mL) and added dropwise over a 1 h period
to a stirred solution of InCl3 (1.31 g, 5.88 mmol) in diethyl ether (50
mL) at 0 °C. Pyridine (ca. 5 mL) was added, and the reaction mixture
was stirred for an additional 16 h, following which it was filtered over
Celite. The volume of the resulting yellow solution was reduced by
Supporting Information Available: Listings of structure refine-
ment details, bond distances, bond angles, atomic coordinates, and
thermal parameters. This material is available free of charge via the
IC980619Q
(19) Sheldrick, G. M. SHELXTL PC, Version 5.0; Siemens Analytical X-ray
Instruments, Inc.: Madison, WI, 1994.