H. Shirase et al.
Bull. Chem. Soc. Jpn. Vol. 82, No. 2 (2009)
231
tion study were grown from the DCE solution kept in a freezer for
several days.
and spectroscopic properties of 1Í5 in the solid state and in
various solvents. From the results of UVÍvis spectra and
electric conductivity measurements, we discuss the effects of
the substituents in diam on the above equilibrium (eq 1) in
nitromethane solution.
[Ni(asym-Et2Me2en)(acac)(NO3)] (3): 3 was obtained by the
same procedures using asym-Et2Me2en. Yield 53%. Anal. Found:
C, 42.78; H, 7.61; N, 11.54%. Calcd for C13H27N3NiO5: C, 42.89;
H, 7.48; N, 11.54%. FAB-MS: m/z 301 ([Ni(Et2Me2en)(acac)]+).
Single crystals suitable for X-ray analysis were grown from the
DCE solution kept in a freezer for several days.
Experimental
Materials.
N,N,N¤,N¤-Tetramethylethylenediamine (Me4en),
[Ni(sym-Et2Me2en)(acac)(NO3)] (3¤): 3¤ synthesize was tried
by the same procedures using sym-Et2Me2en, but product was
obtained only as crude (purity: ca. 90%) due to difficulty in
crystallization. FAB-MS: m/z 301 ([Ni(Et2Me2en)(acac)]+).
[Ni(Et3Meen)(acac)(NO3)] (4): 4 was obtained by the same
procedures using Et3Meen. Yield 46%. Anal. Found: C, 42.96; H,
7.76; N, 11.58%. Calcd for C14H29N3NiO5¢0.5H2O: C, 43.44; H,
7.81; N, 10.86%. FAB-MS: m/z 315 ([Ni(Et3Meen)(acac)]+).
X-ray Crystallography. Intensity data of complexes 2 and 3
were collected by the ½-2ª scan technique on a MacScience
M03XHF four-circle diffractometer with graphite-monochromat-
ized Mo K¡ radiation (- = 0.71073 ¡) at 298 K. The intensities
were corrected for Lorentz and polarization effects and semi-
empirical absorption correction was applied using ¼-scans. The
structure was solved by the direct method with SIR928 and refined
by full-matrix least-squares techniques with SHELX97.9 All non-
hydrogen atoms were refined with anisotropic thermal parameters.
Hydrogen atoms were included in calculated positions. All
drawing and calculations were performed using maXus (Bruker
Nonius, Delft & MacScience, Japan). Crystallographic data and
refinement parameters are listed in Table 1. Crystallographic data
have been deposited with Cambridge Crystallographic Data
Centre. The document numbers are 704827 (2) and 704826 (3).
Copies of the data can be obtained free of charge via http://
Crystallographic Data Centre, 12, Union Road, Cambridge, CB2
1EZ, U.K.; Fax: +44 1223 336033; e-mail: deposit@ccdc.cam.
ac.uk).
N,N,N¤,N¤-tetraethylethylenediamine (Et4en), nickel(II) nitrate
hexahydrate, and acetylacetone were commercially available. All
reagents were used without further purification. [Ni(Me4en)-
(acac)(NO3)] (1) and [Ni(Et4en)(acac)(NO3)] (5) were synthesized
as previously reported.1,2 Solvents of spectro-grade and analytical
grade were used for spectral and electrical measurements,
respectively.
Physical Measurements. Elemental analyses were performed
on a Perkin-Elmer 2400II CHN analyzer. Infrared spectra were
measured with a Perkin-Elmer FT-IR SPECTRUM 2000 as KBr
disks. Mass spectra were obtained on a JEOL JMS-700 Mstation in
the positive fast atom bombardment (FAB) mode using 3-nitro-
benzyl alcohol as matrix. UVÍvis spectra were recorded on a
Shimadzu UV-3100PC spectrophotometer at a concentration of
2.5 © 10Õ2 mol dmÕ3 at room temperature. Electric conductance
was measured with a Conductivity Outfit Model AOC-10 (Denki-
Kagaku-Keiki Co., Ltd.) at 25.0 « 0.1 °C at a concentration of
2.5 © 10Õ2 mol dmÕ3. H NMR spectra (400 MHz) were measured
on a JEOL JNM-AL400 spectrometer in CDCl3.
1
Syntheses of Ligands and Complexes 2Í4. N-Ethyl-N,N¤,N¤-
trimethylethylenediamine (EtMe3en):6,7
N-Ethylethylene-
diamine (4.4 g, 50 mmol) and HCHO (35% aqueous solution,
14.2 g, 165 mmol) were added to HCOOH (17.2 g, 375 mmol) in
an ice bath, and the resultant mixture was refluxed for 24 h. The
solution was cooled to 25 °C and made basic with 2 M aqueous
NaOH. To this mixture, KOH pellets were added until the product
was separated. The liberated amine was extracted with Et2O
(25 mL © 5) and the organic extracts were dried over MgSO4.
After removing the solvent by rotary evaporation, yellow oil
was obtained. Yield 54%. 1H NMR: ¤ 1.060 (t, 3H), 2.24 (9H,
NCH3 © 3), 2.44 (m, 6H).
Table 1. Crystallographic Data and Details of Data Collec-
tion and Refinement
N,N¤-Diethyl-N,N¤-dimethylethylenediamine (sym-Et2Me2en):
N,N¤-Diethylethylenediamine was methylated as described for
EtMe3en. Yield 55%. 1H NMR ¤ 1.059 (t, 6H), 2.236 (s, 6H), 2.43
(m, 8H).
N,N-Diethyl-N¤,N¤-dimethylethylenediamine (asym-Et2Me2en):
N,N-Diethylethylenediamine was methylated as described for
EtMe3en. Yield 70%. 1H NMR ¤ 1.033 (t, 6H), 2.245 (s, 6H),
2.40 (m, 2H), 2.56 (m, 6H).
2
3
Crystal color
Formula
Crystal dimensions
/mm3
Crystal system
Space group
a/¡
b/¡
c/¡
¢/°
V/¡3
green
C12H25N3NiO5
green
C13H27N3NiO5
0.75 © 0.38 © 0.25 0.93 © 0.50 © 0.38
monoclinic
P21/c
monoclinic
P21/c
9.847(6)
10.830(7)
17.39(2)
113.6(2)
1700.0(2)
4
1.368
1.164
27.51
10.064(3)
10.930(5)
17.831(8)
114.81(7)
1780.4(13)
4
1.358
1.114
27.52
3714
N,N,N¤-Triethyl-N¤-methylethylenediamine
(Et3Meen):
N,N,N¤-Triethylethylenediamine was methylated as described for
1
EtMe3en. Yield 60%. H NMR ¤ 1.049 (9H, CH3 © 3), 2.238 (s,
3H), 2.44 (m, 4H), 2.56 (m, 6H).
[Ni(EtMe3en)(acac)(NO3)] (2):
To an ethanol solution of
Z
Ni(NO3)2¢6H2O (2.91 g, 10 mmol), acetylacetone (1.00 g, 10
mmol), and triethylamine (1.01 g, 10 mmol) were added. To this
solution EtMe3en (10 mmol in ethanol) was added dropwise with
vigorous stirring. The resultant green solution was evaporated with
a rotary evaporator, and the residue was recrystallized from 1,2-
dichloroethane (DCE) twice. Green crystals were obtained. Yield
86%. Anal. Found: C, 41.04; H, 7.42; N, 11.99%. Calcd for
C12H25N3NiO5: C, 41.18; H, 7.20; N, 12.00%. FAB-MS: m/z 287
([Ni(EtMe3en)(acac)]+). Single crystals suitable for X-ray diffrac-
Dcalcd/Mg mÕ3
®/mmÕ1
ª
max/°
No. of reflections used 3339
No. of parameters
R
190
200
0.0581
0.1535
1.059
0.0604
0.1581
1.112
Rw
S