V. Pérez et al. / Inorganic Chemistry Communications 14 (2011) 389–391
391
(
(
chloromethyl)benzimidazole (14.0 g, 83.7 mmol) was dissolved in dioxane
280 mL) at 60 °C. After complete dissolution of 2, the reaction mixture was
for the assembly of dicopper(II) complexes with a bridging hydroxide,
and terminal acetate or chloro ligands. The bimetallic complexes have
potential applications as catalysts in enantioselective transformations
due to the chiral nature of the chelating ligands [20], and particularly
considering the C arrangement of the bicyclic backbone. We are
2
currently exploring these possibilities, and will report the results in
forthcoming work.
Supplementary data to this article can be found online at doi:10.1016/
j.inoche.2010.12.008. CCDC 794941 and 794942 contain the supplemen-
tary crystallographic data for this paper. These data can be obtained free of
cooled down to 20 °C, and dimethyl sulfate (15.9 g, 125.5 mmol) was added; the
reaction was then heated to reflux for 1 h, the solvent was evaporated under
vacuum and the solid obtained was suspended in water, followed by addition of
Na
3×25 mL), the organic layer was dried over Na
vacuum. The crude product was purified by flash column chromatography on
silica gel (94:1, CH Cl /MeOH), affording 6.10 g of 1-methyl-2-(chloromethyl)
2
CO
3
to take the mixture to a pH of 8. This was extracted with AcOEt
(
2
SO , and evaporated under
4
2
2
benzimidazole (33.77 mmol, 40% yield).
[
11] Synthesis of (1S, 4S)-2, 5-bis(2-methylbenzimidazolyl)diazabicyclo[2.2.1]hep-
2
1
tane (L
dihydrobromide (3.00 g, 11.53 mmol) in H2O (40 mL), CH
1.86 g, 46.50 mmol), followed by addition of 1-methyl-2-(chloromethyl)benz-
): Procedure analogous to L
with (1S, 4S)-2, 5-diazabicyclo[2.2.1]heptane
2
Cl (40 mL) and NaOH
2
(
2
imidazole (4.20 g, 23.25 mmol) afforded 3.40 g of L (8.80 mmol, 76% yield); Mp
75–180 °C; 1 H NMR (CDCl3): 1 H NMR (CDCl3): δ 7.70 (m, benzimidazole, 2 H),
7.27 (m, benzimidazole, 6 H), 4.03 (d, J=13.35 Hz, CH -benzimidazole, 2 H), 3.92
d, J=13.35 Hz, CH -benzimidazole, 2 H), 3.88 (s, N-Me, 6 H), 3.32 (s, bicycle,
H), 2.94 (d, J=9.90 Hz, bicycle, 2 H), 2.70 (dd, J1=9.90, J2=3.00 Hz, bicycle,
H), 1.78 (s, bicycle, 2 H) ppm. 13 C NMR (CDCl ): δ 152.03, 142.10, 136.32,
1
1
space group P2 , a=9.861(1) Å, b=8.9138(1) Å, c=15.38(2) Å,
2
(
2
2
2
α=90.00 °, β=95.387(2)°, γ=90.00°, V=1346.30(3) Å3. T=298(2)
−3
−1
K, Z=2, Dcalc=1.559 g cm , μ=1.729 mm , 14,831 Reflections
collected, 4907 independent (Rint=0.0497), final R [I≥2σ(I)]=
.0405, wR(F )=0.0897, S=1.021. Data for 2: Mol. wt.=871.92, ortho-
rhombic, space group P2 , a=11.3501(12) Å, b=15.2063(16) Å,
c=23.227(2) Å, α=90.00°, β=90.00°, γ=90.00°, V=4008.8(7) Å .
3
1
122.48, 121.79, 119.52, 109.04, 61.63, 56.83, 51.60, 32.55, 30.06 ppm; IR (KBr,
2
cm−1): ν=3410, 3048, 2967, 2914, 2879, 2839, 1612, 1508, 1474, 1395, 1365,
0
327, 1290, 1241, 1133, 1096, 1008, 933, 856, 815, 542, 431; [α]2
5
=+1.50.
1
D
1 1 1
2 2
[
12] Synthesis of complex (1): In a 100 mL round bottom flask equipped with a stir bar,
3
L1 (293 mg, 1.04 mmol) was dissolved in EtOH (30 mL), solid Cu(OAc)2 (380 mg,
2
materials were evaporated under vacuum, and the deep green oil obtained was
triturated with diethyl ether (20 mL). The green solid was filtered under vacuum,
and washed with additional diethyl ether to afford 368 mg of 1·1.5EtOH
−
3
−1
.09 mmol) was added, and the reaction mixture was stirred for 3 h. Volatile
T=123(2) K, Z=4, Dcalc=1.445 g cm , μ=1.129 mm , 16,614
Reflections collected, 7305 independent (Rint =0.0491), final R
[
1
2
I≥2σ(I)]=0.0440, wR(F )=0.0821, S=0.987.
(
0.52 mmol, 50% yield). Single crystals were obtained by slow evaporation of a
concentrated CH Cl solution. Melting point: 110–115 °C; analysis for
9.5 (1·1.5EtOH): Found: C, 47.61; H, 5.32; N, 8.36%. Calc.: C,
2
2
Acknowledgements
C
28
H
41Cu
2 4
N O
−
1
4
7.18; H, 5.80; N, 7.86%; IR (KBr, cm ): ν=3414, 1573, 1481, 1399, 1338, 1288,
1
The authors thank Eréndira García Ríos for combustion analysis,
Rubén A. Toscano for crystallographic work, Carmen Márquez for
mass spectroscopic assistance, and DGAPA-UNAM (IN211509) and
Conacyt (101855) for financial support; I. R. thanks the Instituto de
Química for the fellowship “Cátedra Especial Jesús Romo Armería”.
1257, 1058, 1023, 931, 770, 677, 620; ESI MS (CH
2
Cl
=−13.12. Complex (2): Analogous procedure with L (200 mg,
2
.51 mmol) and Cu(OAc)2 (188 mg, 1.03 mmol) afforded 305 mg of 2·2H O
2
): m/z=577 [(L )Cu (H O)
2
2
+
25
2
2 D
(OAc) Cl] ; [α]
0
(
0.41 mmol, 80% yield). Single crystals were obtained from a concentrated MeOH/
diethyl ether solution by cooling to −20 °C. Melting point 120–123 °C (dec);
analysis for C29 40Cu (2·2H O): Found: C, 46.95; H, 5.44; N, 10.63%. Calc.: C,
6.83; H, 5.42; N, 11.30%; IR (KBr, cm ): ν=3411, 1574, 1511, 1457, 1399, 1332,
H
2
N
6
O
9
2
−
1
4
2
1
294, 1251, 1063, 1012, 930, 751, 677, 618; ESI MS (EtOH): m/z=647 [(L )Cu (μ-
2
+ 25
References
2 D
OH)(OAc) ] ; [α] =−10.00.
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[
1] S.C. Stinson, Chem. Eng. News 79 (2001) 79.
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structures were solved by direct methods and refined by full-matrix least squares on
F2 with SHELXTL [22]. All non-hydrogen atoms were refined anisotropically, while
hydrogen atoms were refined as riding. CCDC 794941 and 794942 contain the
a=9.861(1) Å, b=8.9138(1) Å, c=15.38(2) Å, α=90.00 °, β=95.387(2)°,
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[
9] Synthesis of (1S, 4S)-2, 5-bis(6-methylpyridyl)diazabicyclo[2.2.1]heptane (L1):
(
1S, 4S)-2, 5-diazabicyclo[2.2.1]heptane dihydrobromide (3.00 g, 11.53 mmol)
was placed in a round bottom flask and dissolved in H O (75 mL), then CH Cl
75 mL) and NaOH (2.95 g, 73.85 mmol) were added. The biphasic reaction was
stirred vigorously, and after 1 h 2-(chloromethyl)pyridine hydrochloride (4.16 g,
5.38 mmol) was added. The mixture was stirred at room temperature for 48 h.
After separation of the phases, the aqueous one was extracted with CH Cl
3×30 mL). The combined organic phases were dried over Na SO and
evaporated under vacuum. The crude product was purified by column
chromatography on silica gel (97:3 CH Cl /MeOH). The collected fractions were
combined, dried over Na SO and evaporated to obtain 2.13 g of L1 (7.60 mmol,
6% yield); 1 H NMR (CDCl3): δ 8.52 (d, J=5.10 Hz, Py, 2 H), 7.65 (t, J=7.90 Hz,
γ=90.00°, V=1346.30(3) Å3. T=298(2) K, Z=2,
Dcalc =1.559 g cm−3,
2
2
2
μ=1.729 mm−1, 14,831 Reflections collected, 4907 independent (Rint=0.0497),
2
(
final R
1
[I≥2σ(I)]=0.0405, wR(F )=0.0897, S=1.021. Data for 2: Mol. wt.=
, a=11.3501(12) Å, b=15.2063(16) Å,
871.92, orthorhombic, space group P2
1 1 1
2 2
3
2
c=23.227(2) Å, α=90.00°, β=90.00°, γ=90.00°, V=4008.8(7) Å . T=123(2) K,
Z=4, Dcalc=1.445 g cm− , μ=1.129 mm , 16,614 Reflections collected, 7305
3
−1
2
2
2
(
2
4
independent (Rint =0.0491), final
S=0.987.
R
1
[I≥2σ(I)]=0.0440, wR(F )=0.0821,
2
2
[17] H. Arora, F. Lloret, R. Mukherjee, Eur. J. Inorg. Chem. (2009) 3317–3325.
[18] D. Wahnon, R.C. Hynes, J. Chin, J. Chem. Soc. Chem. Commun. (1994) 1441–1442.
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[20] H.-L. Kwong, H.-L. Yeung, C.-T. Yeung, W.-S. Lee, C.-S. Lee, W.-L. Wong, Coord.
Chem. Rev. 251 (2007) 2188–2222.
2
4
6
Py, 2 H), 7.49 (d, J=7.90 Hz, Py, 2 H), 7.14 (t, J=5.10 Hz, Py, 2 H), 3.97 (d,
J=14.30 Hz, CH2Py, 2 H), 3.85 (d, J=14.30 Hz, CH2Py, 2 H), 3.38 (d, J=2.30 Hz,
bicycle, 2 H), 2.98 (d, J=9.90 Hz, bicycle, 2 H), 2.77 (dd, J1=9.90, J2=2.60 Hz,
bicycle, 2 H), 1.84 (s, bicycle, 2 H) ppm. 13 C NMR: δ 159.78, 148.95, 136.37,
[21] Y. Njoya, N. Boufatah, A. Gellis, P. Rathelot, M.P. Crozet, P. Vanelle, Heterocycles 57
(2002) 1423–1432.
1
2
1
22.61, 121.74, 62.23, 60.24, 56.68, 33.77 ppm. IR (KBr, cm−1): ν=3399, 3056,
[22] G.M. Sheldrick, SHELXTL, v. 6.10, University of Göttingen, Madison, WI, 20008
(distributed by Bruker-AXS Inc.).
961, 2919, 2854, 1666, 1591, 1570, 1473, 1432, 1365, 1327, 1219, 1145, 1087,
047, 996, 937, 811, 756, 724, 613; [α]2
5
=+1.25.
D
[10] 1-Methyl-2-(chloromethyl)benzimidazole was prepared according to a modified
procedure [21]: In a 500 mL round bottom flask equipped with a stir bar, 2-