Journal of Inorganic and General Chemistry
www.zaac.wiley-vch.de
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
actopyranose (2).[11] The ratio of 2 started increasing in solu- 1D and 2D NMR experiments, DEPT135, H- H-COSY, H- C-
1
1
1
13
1
13
HMQC and H- C-HMBC, were measured to identify the assignment
of the NMR signals. Shift differences (Δδ, CIS values) are given as
Δδ = δ(Ccomplex) – δ(Cfree ligand). To identify the conformation and con-
figuration of d-galactosylamine the C NMR values and the
coupling constants were analysed, the latter with regard to the Karplus
tion after a reaction time of 7 h. Furthermore both furanose
forms (1βf, 1αf) and the α-pyranose form (1αp) were observed.
To obtain d-galactosylamine as a solid, the reaction solution
was kept at 4 °C for 2–3 months. Depending on the amount of
methanol and the reaction time, the composition of the precipi-
tated solid varied. To obtain pure 1βp with an isolated yield of
1
3
3
J
H,H
[13]
relationship.
All reaction mixtures were stored at –25 °C until the
NMR spectra were recorded.
60–70%, a reaction of d-galactose (1 g) in a solution of ammo-
Single-crystal X-ray Analysis: Crystals were selected with a polarisa-
tion microscope Leica MZ6 and mounted on the tip of a glass fibre.
The measurement was performed with a Nonius KappaCCD dif-
nia in methanol (30–40 mL) with a reaction time of 4–5 h was
suitable. Another reaction with larger amounts of d-galactose
(4 g) and methanol and a shorter reaction time resulted in a
α
fractometer at 173 K with Mo-K radiation (λ = 0.71073 Å, graded
precipitated solid containing d-galactose, 1βp, 1αp, and 1βf.
This solid was dissolved in ammonia in methanol and after the
reaction a precipitated solid containing 1βp and 1αp (ratio
multilayer mirrors). The structure was solved by direct methods
2
(
(
SHELXS) and refined by full-matrix, least-squares calculations on F
SHELXL-97). Anisotropic displacement parameters were refined for
17:1) was obtained.
all non-hydrogen atoms. For the puckering analysis PLATON was used
and ORTEP was applied to draw the molecular structure. Details of
the crystal structure analysis of 3Cl
2 2
·3H O are shown in Table 1.
Conclusions
Crystallographic data (excluding structure factors) for the structure in
In this work, d-galactosylamine (1) was studied as a ligand this paper have been deposited with the Cambridge Crystallographic
towards cobalt(III) fragments. In fact, the same binding site Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK. Copies
III
II
was observed for Co and Pd in terms of both NMR spec- of the data can be obtained free of charge on quoting the depository
number CCDC-1056314 (3Cl ·3H O) (Fax: +44-1223-336-033;
E-Mail: deposit@ccdc.cam.ac.uk, http://www.ccdc.cam.ac.uk).
troscopy and single-crystal X-ray structure analysis on a salt of
2
2
2
1
2 2+
the complex dication [Co(tren)(β-d-Galp1N2H -κ N ,O )]
–
1
(
3). The central metal ion was coordinated via the anomeric
-Galactosylamine (1):[14] d-Galactose (2.0 g, 11 mmol,
.0 equiv.) and a solution of ammonia in methanol (80 mL, 7 m,
0.56 mol, 50 equiv.) were stirred at 50 °C for 8 h, while a low pressure
Synthesis of
1
D
amino group (N1) and the deprotonated hydroxy group (O2)
in a five-membered chelate ring. The C conformation and
4
1
the β configuration of free d-galactosylamine were maintained was built up. The solution was stored at 4 °C for three months. The
in 3, 4 and 5. The CIS values of C1 lay between 1.4 ppm to colourless precipitation was filtered, washed with cold methanol
2
.5 ppm, and of C2 between 3.6 ppm to 3.8 ppm. These values (2ϫ10 mL) and diethyl ether (2ϫ10 mL) and dried in vacuo. The
1
yield was 1.5 g (8.5 mmol, 76%). 1βp: H NMR (400 MHz, D
2
O): δ
of C1 agreed with the typical range for palladium(II) coordina-
tion, with the values of C2 lower in comparison to Pd coordi-
3
3
II
= 3.99 (d, 1 H, H1, J1,2 = 8.7 Hz), 3.89 (dd, 1 H, H4, J4,5 = 1.0 Hz),
.69 (m, 2 H, H6), 3.62 (ddd, 1 H, H5, J5,6a = 3.6, J5,6b = 7.6 Hz),
.59 (dd, 1 H, H3, J3,4 = 3.4 Hz), 3.35 (dd, 1 H, H2, J2,3 = 9.6 Hz)
3
3
3
3
nation. Specifically, an anomeric equilibrium in solution was
3
3
4
observed. In aqueous solution, the C β-pyranose is the major
1
13
1
ppm. C{ H} NMR (101 MHz, D
C3), 72.6 (C2), 69.6 (C4), 61.8 (C6) ppm. C{ H} NMR (101 MHz,
[D ]DMSO): δ = 87.1 (C1), 76.0 (C5), 74.0 (C3), 72.5 (C2), 68.6 (C4),
2
O): δ = 86.2 (C1), 76.6 (C5), 74.1
form. Both pyranoses (1βp, 1αp) and both furanose forms (1βf,
13
1
(
1
αf) were characterised in anhydrous [D ]DMSO and iden-
6
6
tified in D O. It turned out that d-galactosylamine (1) is a true
1
2
6
60.7 (C6) ppm. 1αp: H NMR (400 MHz, [D ]DMSO): δ = 3.76 (d,
3
13
1
reducing sugar derivative. Hence, d-galactosylamine can serve 1 H, H1, J1,2 = 4.0 Hz), 3.45 (sp, 2 H, H6) ppm. C{ H} NMR
as a dynamic ligand library and various cyclic forms are avail- (101 MHz, [D ]DMSO): δ = 82.0 (C1), 69.6 (C3, C5), 68.7 (C4), 68.4
6
1
3
1
able for metal coordination.
(C2), 60.6 (C6) ppm. C{ H} NMR (101 MHz, D
2
O, 4 °C): δ = 81.9
C1), 70.4 (C3/C5), 69.8 (C3/C5), 69.5 (C4), 68.4 (C2), 61.7 (C6)
(
1
ppm. 1βf: H NMR (400 MHz, [D
6
]DMSO): δ = 4.37 (d, 1 H, H1,
3
J
1,2 = 4.7 Hz), 3.86 (sp, 1 H, H3), 3.63 (sp, 1 H, H4), 3.51 (sp, 1 H,
Experimental Section
1
3
1
H2), 3.32 (sp, 2 H, H6), 3.20 (dd, 1 H, H5) ppm. C{ H} NMR
Methods and Materials: The chemicals, which were purchased from (101 MHz, [D ]DMSO): δ = 90.6 (C1), 82.2 (C4), 81.1 (C2), 77.1
6
1
Acros, Aldrich, Euriso-top, Fluka, Merck, Sigma Aldrich and VWR, (C3), 71.0 (C5), 62.8 (C6) ppm. H NMR (400 MHz, D O, 4 °C): δ =
were used without further purification. The cobalt(III) compounds 4.56 (d, 1 H, H1, J = 5.0 Hz) ppm. C{ H} NMR (101 MHz, D O,
were synthesised as described in the literature. All reaction mixtures 4 °C): δ = 89.3 (C1), 82.4 (C4), 80.8 (C2), 77.9 (C3), 71.5 (C5), 63.3
(C6) ppm. 1αf: H NMR (400 MHz, [D ]DMSO): δ = 4.63 (d, 1 H,
carbohydrate derivative. For the elemental analyses an Elementar EL H1, J = 3.9 Hz), 3.86 (sp, 1 H, H3), 3.73 (dd, 1 H, H4, J = 6.1,
2
3
13
1
1
,2
2
[
12]
1
with d-galactosylamine were stirred at 4 °C to avoid hydrolysis of the
6
3
3
1
,2
3,4
3
3
Apparatur was used.
2,3
J4,5 = 2.5 Hz), 3.56 (dd, 1 H, H2, J = 3.3 Hz), 3.45 (sp, 1 H, H5),
.35 (sp, 2 H, H6) ppm. C{ H} NMR (101 MHz, [D
5.8 (C1), 80.8 (C4), 76.5 (C2), 76.4 (C3), 71.2 (C5), 62.8 (C6) ppm.
1
3
1
3
8
1
6
]DMSO): δ =
NMR Spectroscopy: NMR spectra were recorded at room temperature
(
(
22–24 °C) with Jeol ECX 400 and Jeol Eclipse 400 spectrometers
3
H NMR (400 MHz, D
2
O, 4 °C): δ = 4.58 (d, 1 H, H1, J1,2 = 3.5 Hz)
O, 4 °C): δ = 86.6 (C1), 80.6 (C4),
6.7 (C2), 76.0 (C3), 72.0 (C5), 63.3 (C6) ppm. C : calcd. C
0.22; H 7.31; N 7.82%; found: C 40.04; H 7.22; N 7.75%.
1
13
1
1
H: 400 MHz, C{ H}: 100 MHz). For the H NMR spectra the re-
O or the anhydrous [D ]DMSO were used as
an internal standard, for the 13C{ H} NMR spectra a drop of methanol
was added (referenced to 49.5 ppm) to the solutions in D O. The sig-
13
1
ppm. C{ H} NMR (101 MHz, D
2
sidual protons of the D
2
6
7
4
6 5
H13NO
1
2
1
3
1
nals of the deuterated solvent were used as a reference for the C{ H} Synthesis of the Complexes: For the NMR investigation the reactions
NMR spectra of the solution in [D ]DMSO. When necessary, various of d-galactosylamine with the various cobalt(III) precursors were car-
6
Z. Anorg. Allg. Chem. 2015, 1869–1873
1872
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