μ-Chlorido-1:2κ²Cl:Cl-trichlorido-2κ³Cl-[tris­(2-amino­ethyl)amine-1κ⁴N,N′,N′′,N′′′]dimercury(II)

In the title complex, [Hg₂Cl₄(C₆H₁₈N₄)], one Hg^II ion is coordinated by four N atoms from a tris­(2-amino­ethyl)amine ligand and one Cl atom of a tetra­chlorido­mercurate group in a distorted trigonal–bipyramidal geometry. The Cl atom occupies an axial position and bridges to a second Hg^II ion, which is coordinated in a distorted tetra­hedral geometry by four Cl atoms. The bonds involving the bridging Cl atom are significantly longer than the other Hg—Cl bonds. In the crystal structure, mol­ecules are linked by inter­molecular N—H...Cl hydrogen bonds into a two-dimensional network, which is further stabilized by weak inter­molecular C—H...Cl hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.016 Å
• R factor = 0.038
• wR factor = 0.103
• Data-to-parameter ratio = 19.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.81
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.36
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Hg1    -   Cl1     ..       9.76 su
PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...         16
PLAT420_ALERT_2_C D-H Without Acceptor       N4     -   H4A    ...          ?
PLAT420_ALERT_2_C D-H Without Acceptor       N4     -   H4B    ...          ?

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.357
            Tmax scaled      0.058 Tmin scaled      0.054
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   6 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Research of organic polyamines is currently of great insterest because of their potential applications as useful organic ligands, in which the amine nitrogen atoms have strong coordination ablity to transition metal ions and recongnition function (Adam et al., 1988; Marchetti et al., 1989; Dakternicks, 1990; Adam et al., 1994). Their transition metal complexes play an excellent role in catalysis and mimic studies on dismutase and chlorophyll (Gou et al., 1993; Cai et al., 1997; Wang et al., 1997). In this paper, we report the synthesis and crystal structure of the title compound.

The molecular structure of the title bimetallic and bridged complex (C₆H₁₈N₄)Hg—Cl—HgCl₃ (I) is shown in Fig. 1. The coordination geometry around Hg1 atom can be described as distorted trigonal bipyramidal with the axial positions occupied by the N1 and Cl1 atoms (N1— Hg1— Cl1 = 172.4 (2) °). Atom Hg2 is four-coordinated in a distorted tetrahedral coordination geometry by one bridging Cl atoms and three terminal Cl atoms. The bond distances of Hg—N are in the range of 2.308 (8) – 2.521 (8) Å, the bond distances of Hg—Cl are in the range of 2.361 (3) – 2.785 (3) Å. Tris(2-aminoethyl)amine ligand consists of three five-membered chelate rings, the dihedral angle between the mean planes of these chelate rings range from 55.80 (0.28) to to 64.12 (0.31) °.

In the crystal structure, adjacent molecules are linked by intermolecular N—H···Cl hydrogen bonds into a two-dimensional network which is further stabilzed by weak intermolecular C—H···Cl hydrogen bonds (Fig. 2).

Related literature

For general background, see: Adam et al. (1988); Gou et al. (1993); Cai et al. (1997); Wang et al. (1997). For related structures, see: Marchetti et al. (1989); Dakternicks (1990); Adam et al. (1994)

S2. Experimental

Tris(2-aminoethyl)amine (2 mmol, 292.5 mg) in hot absolute ethanol (10 ml) was added dropwise to a absolute ethanol solution (20 ml) of mercury chloride (4 mmol, 868.8 mg). The mixture was heated under reflux with stirring for 5 h. The solution was kept at room temperature for about 20 days, after which large yellow block-shaped crystals of the title complex suitable for X-ray diffraction analysis were obtained.

S3. Refinement

All H-atoms were positioned geometrically and refined using a riding model, with C—H 0.97 (methylene) and N—H (amino) 0.90 Å, withU_iso(H) =1.2U_eq(C,N).

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

	Fig. 1. The molecular structure of the title complex, showing 30% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. Part of the crystal structure showing hydrogen bonds as dashed lines.

µ-Chlorido-1:2κ²Cl-trichlorido-2κ³Cl-[tris(2-aminoethyl)amine-\ 1κ⁴N,N',N'',N''']dimercury(II)

Crystal data

[Hg2Cl4(C6H18N4)]	F(000) = 1240
Mr = 689.22	Dx = 2.930 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P2ybc	Cell parameters from 3679 reflections
a = 10.4378 (6) Å	θ = 2.4–27.5°
b = 11.5537 (8) Å	µ = 20.30 mm^−1
c = 13.1306 (10) Å	T = 298 K
β = 99.395 (1)°	Block, yellow
V = 1562.25 (18) Å^3	0.15 × 0.14 × 0.14 mm
Z = 4

Data collection

Siemens SMART CCD area-detector diffractometer	2245 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.058
ϕ and ω scans	θmax = 25.0°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→12
Tmin = 0.151, Tmax = 0.163	k = −13→13
7516 measured reflections	l = −15→11
2757 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.103	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0433P)^2 + 0.6626P] where P = (Fo^2 + 2Fc^2)/3
2757 reflections	(Δ/σ)max = 0.001
139 parameters	Δρmax = 1.69 e Å^−3
1 restraint	Δρmin = −1.45 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Hg1	0.11574 (4)	0.36983 (3)	0.70931 (3)	0.03894 (16)
Hg2	−0.27774 (4)	0.42828 (4)	0.61195 (3)	0.04422 (17)
Cl1	−0.0774 (2)	0.2723 (2)	0.5996 (2)	0.04422 (17)
Cl2	−0.4650 (3)	0.3269 (3)	0.5348 (2)	0.0615 (8)
Cl3	−0.1733 (3)	0.5903 (2)	0.5366 (2)	0.0507 (7)
Cl4	−0.2391 (3)	0.4612 (3)	0.7999 (2)	0.0567 (8)
N1	0.3069 (7)	0.4444 (7)	0.8345 (6)	0.0341 (19)
N2	0.2892 (8)	0.2545 (7)	0.6860 (7)	0.042 (2)
H2A	0.2621	0.1810	0.6746	0.051*
H2B	0.3217	0.2789	0.6304	0.051*
N3	0.0576 (8)	0.3501 (8)	0.8729 (7)	0.044 (2)
H3A	−0.0271	0.3672	0.8698	0.052*
H3B	0.0701	0.2765	0.8947	0.052*
N4	0.1280 (9)	0.5653 (8)	0.6750 (8)	0.051 (2)
H4A	0.1026	0.5784	0.6072	0.061*
H4B	0.0752	0.6050	0.7101	0.061*
C1	0.4199 (10)	0.3836 (10)	0.8101 (9)	0.045 (3)
H1A	0.4875	0.3843	0.8703	0.054*
H1B	0.4524	0.4243	0.7550	0.054*
C2	0.3906 (10)	0.2588 (10)	0.7772 (8)	0.043 (3)
H2C	0.4688	0.2223	0.7616	0.052*
H2D	0.3623	0.2164	0.8333	0.052*
C3	0.2799 (9)	0.4150 (9)	0.9393 (7)	0.038 (2)
H3C	0.3298	0.4658	0.9897	0.045*
H3D	0.3071	0.3361	0.9561	0.045*
C4	0.1357 (10)	0.4275 (10)	0.9452 (8)	0.045 (3)
H4C	0.1216	0.4101	1.0148	0.054*
H4D	0.1089	0.5068	0.9298	0.054*
C5	0.3144 (11)	0.5708 (9)	0.8183 (9)	0.047 (3)
H5A	0.4038	0.5959	0.8373	0.057*
H5B	0.2630	0.6102	0.8630	0.057*
C6	0.2654 (11)	0.6044 (10)	0.7069 (10)	0.055 (3)
H6A	0.2702	0.6877	0.6995	0.066*
H6B	0.3200	0.5692	0.6624	0.066*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Hg1	0.0296 (3)	0.0429 (3)	0.0411 (3)	−0.00315 (17)	−0.00385 (17)	−0.00563 (17)
Hg2	0.0362 (3)	0.0502 (3)	0.0459 (3)	−0.01336 (18)	0.00534 (19)	−0.00858 (19)
Cl1	0.0362 (3)	0.0502 (3)	0.0459 (3)	−0.01336 (18)	0.00534 (19)	−0.00858 (19)
Cl2	0.0410 (16)	0.077 (2)	0.061 (2)	−0.0240 (15)	−0.0089 (13)	−0.0014 (16)
Cl3	0.0464 (16)	0.0447 (15)	0.0605 (19)	−0.0098 (13)	0.0075 (13)	0.0081 (13)
Cl4	0.0558 (18)	0.0717 (19)	0.0395 (17)	0.0081 (15)	−0.0019 (13)	−0.0160 (14)
N1	0.027 (4)	0.040 (5)	0.036 (5)	0.000 (4)	0.005 (3)	−0.007 (4)
N2	0.054 (5)	0.039 (5)	0.034 (5)	0.006 (4)	0.008 (4)	−0.010 (4)
N3	0.031 (5)	0.056 (6)	0.045 (6)	−0.007 (4)	0.009 (4)	0.003 (4)
N4	0.049 (6)	0.044 (6)	0.054 (6)	0.012 (4)	−0.005 (4)	0.006 (4)
C1	0.022 (5)	0.068 (8)	0.045 (7)	0.009 (5)	0.007 (4)	−0.006 (6)
C2	0.035 (6)	0.056 (7)	0.040 (6)	0.012 (5)	0.009 (5)	0.001 (5)
C3	0.034 (6)	0.054 (6)	0.023 (5)	0.000 (5)	0.000 (4)	−0.010 (5)
C4	0.044 (6)	0.059 (7)	0.036 (6)	0.007 (5)	0.014 (5)	−0.006 (5)
C5	0.054 (7)	0.039 (6)	0.049 (7)	−0.017 (5)	0.009 (5)	−0.010 (5)
C6	0.054 (8)	0.045 (6)	0.067 (9)	−0.001 (6)	0.015 (6)	0.008 (6)

Geometric parameters (Å, º)

Hg1—N2	2.308 (8)	N4—C6	1.497 (14)
Hg1—N4	2.310 (9)	N4—H4A	0.9000
Hg1—N3	2.337 (8)	N4—H4B	0.9000
Hg1—N1	2.521 (8)	C1—C2	1.521 (16)
Hg1—Cl1	2.542 (2)	C1—H1A	0.9700
Hg2—Cl2	2.361 (3)	C1—H1B	0.9700
Hg2—Cl3	2.454 (3)	C2—H2C	0.9700
Hg2—Cl4	2.465 (3)	C2—H2D	0.9700
Hg2—Cl1	2.785 (3)	C3—C4	1.526 (13)
N1—C1	1.452 (12)	C3—H3C	0.9700
N1—C5	1.480 (13)	C3—H3D	0.9700
N1—C3	1.488 (13)	C4—H4C	0.9700
N2—C2	1.463 (13)	C4—H4D	0.9700
N2—H2A	0.9000	C5—C6	1.519 (16)
N2—H2B	0.9000	C5—H5A	0.9700
N3—C4	1.453 (13)	C5—H5B	0.9700
N3—H3A	0.9000	C6—H6A	0.9700
N3—H3B	0.9000	C6—H6B	0.9700
N2—Hg1—N4	118.0 (3)	Hg1—N4—H4B	109.9
N2—Hg1—N3	113.1 (3)	H4A—N4—H4B	108.3
N4—Hg1—N3	107.8 (3)	N1—C1—C2	112.8 (8)
N2—Hg1—N1	74.3 (3)	N1—C1—H1A	109.0
N4—Hg1—N1	74.3 (3)	C2—C1—H1A	109.0
N3—Hg1—N1	74.4 (3)	N1—C1—H1B	109.0
N2—Hg1—Cl1	103.6 (2)	C2—C1—H1B	109.0
N4—Hg1—Cl1	112.8 (2)	H1A—C1—H1B	107.8
N3—Hg1—Cl1	100.2 (2)	N2—C2—C1	110.5 (9)
N1—Hg1—Cl1	172.4 (2)	N2—C2—H2C	109.6
Cl2—Hg2—Cl3	126.63 (10)	C1—C2—H2C	109.6
Cl2—Hg2—Cl4	119.67 (11)	N2—C2—H2D	109.6
Cl3—Hg2—Cl4	105.97 (11)	C1—C2—H2D	109.6
Cl2—Hg2—Cl1	103.36 (10)	H2C—C2—H2D	108.1
Cl3—Hg2—Cl1	94.75 (9)	N1—C3—C4	111.3 (8)
Cl4—Hg2—Cl1	99.00 (9)	N1—C3—H3C	109.4
Hg1—Cl1—Hg2	102.34 (9)	C4—C3—H3C	109.4
C1—N1—C5	112.5 (8)	N1—C3—H3D	109.4
C1—N1—C3	112.1 (8)	C4—C3—H3D	109.4
C5—N1—C3	112.3 (8)	H3C—C3—H3D	108.0
C1—N1—Hg1	106.0 (6)	N3—C4—C3	111.2 (8)
C5—N1—Hg1	107.4 (6)	N3—C4—H4C	109.4
C3—N1—Hg1	106.0 (5)	C3—C4—H4C	109.4
C2—N2—Hg1	110.5 (6)	N3—C4—H4D	109.4
C2—N2—H2A	109.6	C3—C4—H4D	109.4
Hg1—N2—H2A	109.6	H4C—C4—H4D	108.0
C2—N2—H2B	109.6	N1—C5—C6	111.9 (9)
Hg1—N2—H2B	109.6	N1—C5—H5A	109.2
H2A—N2—H2B	108.1	C6—C5—H5A	109.2
C4—N3—Hg1	109.8 (6)	N1—C5—H5B	109.2
C4—N3—H3A	109.7	C6—C5—H5B	109.2
Hg1—N3—H3A	109.7	H5A—C5—H5B	107.9
C4—N3—H3B	109.7	N4—C6—C5	110.4 (9)
Hg1—N3—H3B	109.7	N4—C6—H6A	109.6
H3A—N3—H3B	108.2	C5—C6—H6A	109.6
C6—N4—Hg1	108.8 (6)	N4—C6—H6B	109.6
C6—N4—H4A	109.9	C5—C6—H6B	109.6
Hg1—N4—H4A	109.9	H6A—C6—H6B	108.1
C6—N4—H4B	109.9

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···Cl3^i	0.90	2.51	3.378 (9)	163
N2—H2B···Cl2^ii	0.90	2.78	3.590 (9)	150
N2—H2A···Cl4^i	0.90	2.58	3.438 (9)	160
C5—H5B···Cl1^iii	0.97	2.80	3.684 (12)	153

Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) x+1, y, z; (iii) −x, y+1/2, −z+3/2.