[2-(Dimethyl­amino)­ethanol-κ2N,O][2-(dimethyl­amino)­ethano­lato-κ2N,O]iodidocopper(II)

Buvaylo, E.A.; Kokozay, V.N.; Vassilyeva, O.Y.; Skelton, B.W.

doi:10.1107/S1600536812010215

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Pages m419-m420

doi:10.1107/S1600536812010215

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[2-(Dimethylamino)ethanol-κ²N,O][2-(dimethylamino)ethanolato-κ²N,O]iodidocopper(II)

Elena A. Buvaylo,^a Volodymyr N. Kokozay,^a Olga Yu. Vassilyeva ^a ^* and Brian W. Skelton ^b

^aDepartment of Inorganic Chemistry, Taras Shevchenko National University of Kyiv, Volodymyrska str. 64, Kyiv 01033, Ukraine, and ^bCentre for Microscopy, Characterisation and Analysis, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
^*Correspondence e-mail: vassilyeva@univ.kiev.ua

(Received 15 February 2012; accepted 7 March 2012; online 14 March 2012)

The title compound, [Cu(C₄H₁₀NO)I(C₄H₁₁NO)], was obtained unintentionally as the product of an attempted synthesis of a Cu/Zn mixed-metal complex using zerovalent copper, zinc(II) oxide and ammonium iodide in pure 2-(dimethylamino)ethanol, in air. The molecular complex has no crystallographically imposed symmetry. The coordination geometry around the metal atom is distorted square-pyramidal. The equatorial coordination around copper involves donor atoms of the bidentate chelating 2-(dimethylamino)ethanol ligand and the 2-(dimethylamino)ethanolate group, which are mutually trans to each other, with four approximately equal short Cu—O/N bond distances. The axial Cu—I bond is substantially elongated. Intermolecular hydrogen-bonding interactions involving the –OH group of the neutral 2-(dimethylamino)ethanol ligand to the O atom of the monodeprotonated 2-(dimethylamino)ethanolate group of the molecule related by the n-glide plane, as indicated by the O⋯O distance of 2.482 (12) Å, form chains of molecules propagating along [101].

Related literature

For background to the synthesis, see: Vinogradova et al. (2002 ). Buvaylo et al. (2009 , 2011 ). Elongation of the axial Cu—I bond is common in this kind of compound, see: Wells (1986 ).

Experimental

Crystal data

[Cu(C₄H₁₀NO)I(C₄H₁₁NO)]
M_r = 367.71
Monoclinic, P 2₁ /n
a = 8.690 (1) Å
b = 15.241 (1) Å
c = 11.116 (1) Å
β = 106.847 (10)°
V = 1409.1 (2) Å³
Z = 4
Mo Kα radiation
μ = 3.72 mm⁻¹
T = 296 K
0.32 × 0.3 × 0.2 mm

Data collection

Rigaku AFC-6S diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.333, T_max = 0.47
2642 measured reflections
2471 independent reflections
1003 reflections with I > 2σ(I)
R_int = 0.089
3 standard reflections every 150 reflections intensity decay: none

Refinement

R[F² > 2σ(F²)] = 0.058
wR(F²) = 0.204
S = 1.00
2471 reflections
133 parameters
H-atom parameters constrained
Δρ_max = 1.80 e Å⁻³
Δρ_min = −0.83 e Å⁻³

Table 1
Selected bond lengths (Å)

I1—Cu1	2.928 (2)
Cu1—O1	2.030 (9)
Cu1—N2	2.058 (11)
Cu1—N1	2.059 (10)
Cu1—O2	2.010 (8)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2O⋯O1ⁱ	0.82	1.68	2.482 (12)	167
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: AFC6S Diffractometer Control Software (Molecular Structure Corporation, 1998) $[Molecular Structure Corporation (1998). AFC6S Diffractometer Control Software. MSC, The Woodlands, Texas, USA.]$ ; cell refinement: AFC6S Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2000 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Johnson (1976 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812010215/ds2178sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812010215/ds2178Isup2.hkl

checkCIF report

Comment top

In our previous study metal powders of zinc and copper were found to react with ammonium iodide and 2-(dimethylamino)ethanol (HMe₂Ea) in methanol, in air, affording the new heterotrinuclear complex [Cu₂Zn(NH₃)I₃(Me₂Ea)₃] (Vinogradova et al., 2002). Reactions employing elemental copper and aminoalcohol allow in situ formation of the metal aminoalkoxo species - key building blocks that can subsequently self-assemble with other metal centres present in the reaction vessel (Buvaylo et al., 2009; Buvaylo et al., 2011). The title compound was isolated from the solution obtained by reacting copper powder and zinc oxide with ammonium iodide in pure 2-(dimethylamino)ethanol. It can be considered as an intermediate, a building block that failed self-organization with another metal species produced in the reaction medium. To the best of our knowledge the title compound has not been structurally characterized.

The molecular complex has no crystallographically imposed symmetry (Fig. 1). The coordination geometry around the metal atom is distorted square pyramidal. The equatorial coordination around Cu(1) involves donor atoms of bidentate chelating 2-(dimethylamino)ethanol and 2-(dimethylamino)ethanolato group, which are mutually trans to each other, with four approximately equal short distances. The axial Cu(1)–I(1) bond is substantially elongated [2.928 (2) Å], and it is common for this kind of compounds (Wells, 1986).

Intermolecular hydrogen-bonding interactions from the OH group of neutral 2-(dimethylamino)ethanol ligand to O atom of monodeprotonated 2-(dimethylamino)ethanolato group of the molecule related by the n glide plane [H2O···O1{x - 1/2, -y + 1/2, z - 1/2} = 1.68 Å; O2···O1{x - 1/2, -y + 1/2, z - 1/2} = 2.482 (12) Å and O2—H2O···O1{x - 1/2, -y + 1/2, z - 1/2} = 167.3°] form chains of Cu(Me₂Ea)(HMe₂Ea)I molecules propagated along the 101 direction (Fig. 2). Cu···Cu separations in the crystal are > 6.6 Å.

Related literature top

For background to the synthesis, see: Vinogradova et al. (2002). Buvaylo et al. (2009, 2011). Elongation of the axial Cu—I bond is common in this kind of compound, see: Wells (1986).

Experimental top

Copper powder (0.16 g, 2.5 mmol), ZnO (0.20 g, 2.5 mmol), NH₄I (1.45 g, 10 mmol), HMe₂Ea (15 ml) were heated to 323–333 K and magnetically stirred until total dissolution of the copper and ZnO was observed (95 min). The resulting blue solution was filtered and allowed to stand at room temperature. Green-blue microcrystals of the title compound were formed after one day. They were collected by filter-suction, washed with dry PrⁱOH and finally dried in vacuo (yield: 0.23 g).

Structure description top

For background to the synthesis, see: Vinogradova et al. (2002). Buvaylo et al. (2009, 2011). Elongation of the axial Cu—I bond is common in this kind of compound, see: Wells (1986).

Computing details top

Data collection: AFC6S Diffractometer Control Software (Molecular Structure Corporation, 1998); cell refinement: AFC6S Diffractometer Control Software (Molecular Structure Corporation, 1998); data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Johnson (1976); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. Molecular structure of the complex with the numbering scheme (the non-hydrogen atoms shown as 20% thermal ellipsoids).
	Fig. 2. Hydrogen-bonding interactions between Cu(Me₂Ea)(HMe₂Ea)I molecules within a polymeric chain.

[2-(Dimethylamino)ethanol-κ²N,O][2-(dimethylamino)ethanolato- κ²N,O]iodidocopper(II) top

Crystal data top

[Cu(C₄H₁₀NO)I(C₄H₁₁NO)]	F(000) = 724
M_r = 367.71	D_x = 1.733 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -p 2yn	Cell parameters from 6 reflections
a = 8.690 (1) Å	θ = 10.9–11.9°
b = 15.241 (1) Å	µ = 3.72 mm⁻¹
c = 11.116 (1) Å	T = 296 K
β = 106.847 (10)°	Rod, blue-green
V = 1409.1 (2) Å³	0.32 × 0.3 × 0.2 mm
Z = 4

Data collection top

Rigaku AFC-6S diffractometer	1003 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.089
Graphite monochromator	θ_max = 25°, θ_min = 2.3°
2θ–ω scans	h = 0→10
Absorption correction: ψ scan (North et al., 1968)	k = 0→18
T_min = 0.333, T_max = 0.47	l = −13→12
2642 measured reflections	3 standard reflections every 150 reflections
2471 independent reflections	intensity decay: none

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.058	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.204	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.0962P)²] where P = (F_o² + 2F_c²)/3
2471 reflections	(Δ/σ)_max = 0.013
133 parameters	Δρ_max = 1.80 e Å⁻³
0 restraints	Δρ_min = −0.83 e Å⁻³

Crystal data top

[Cu(C₄H₁₀NO)I(C₄H₁₁NO)]	V = 1409.1 (2) Å³
M_r = 367.71	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.690 (1) Å	µ = 3.72 mm⁻¹
b = 15.241 (1) Å	T = 296 K
c = 11.116 (1) Å	0.32 × 0.3 × 0.2 mm
β = 106.847 (10)°

Data collection top

Rigaku AFC-6S diffractometer	1003 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.089
T_min = 0.333, T_max = 0.47	3 standard reflections every 150 reflections
2642 measured reflections	intensity decay: none
2471 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	0 restraints
wR(F²) = 0.204	H-atom parameters constrained
S = 1.00	Δρ_max = 1.80 e Å⁻³
2471 reflections	Δρ_min = −0.83 e Å⁻³
133 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
I1	0.64794 (15)	0.39539 (8)	0.25072 (11)	0.0679 (5)
Cu1	0.4723 (2)	0.26167 (12)	0.34694 (15)	0.0456 (6)
O1	0.5633 (10)	0.2803 (6)	0.5351 (8)	0.044 (2)
O2	0.3381 (11)	0.2106 (6)	0.1834 (8)	0.038 (2)
H2O	0.2428	0.2147	0.1437	0.08 (6)*
N1	0.2813 (13)	0.3302 (7)	0.3748 (9)	0.038 (3)
N2	0.6101 (12)	0.1521 (7)	0.3455 (9)	0.033 (3)
C1	0.4697 (16)	0.3364 (10)	0.5848 (13)	0.050 (4)
H1A	0.5391	0.3755	0.6457	0.06*
H1B	0.4074	0.3021	0.6276	0.06*
C2	0.3579 (18)	0.3894 (9)	0.4808 (13)	0.048 (4)
H2A	0.2761	0.4173	0.5113	0.057*
H2B	0.4178	0.4349	0.453	0.057*
C3	0.1879 (19)	0.3814 (10)	0.2666 (13)	0.061 (5)
H3A	0.0986	0.4086	0.2864	0.092*
H3B	0.1488	0.3434	0.1954	0.092*
H3C	0.2551	0.4259	0.247	0.092*
C4	0.1717 (17)	0.2652 (10)	0.4069 (14)	0.052 (4)
H4A	0.0854	0.2955	0.427	0.079*
H4B	0.2304	0.2311	0.4781	0.079*
H4C	0.1284	0.2271	0.3365	0.079*
C5	0.4044 (16)	0.1367 (9)	0.1424 (13)	0.046 (4)
H5A	0.3869	0.1398	0.0523	0.055*
H5B	0.3528	0.0839	0.1607	0.055*
C6	0.5814 (15)	0.1335 (9)	0.2087 (11)	0.038 (3)
H6A	0.6234	0.0759	0.198	0.045*
H6B	0.637	0.1766	0.1725	0.045*
C7	0.7829 (17)	0.1630 (11)	0.4054 (13)	0.059 (5)
H7A	0.8063	0.1534	0.4942	0.089*
H7B	0.8144	0.2215	0.3905	0.089*
H7C	0.8413	0.1214	0.3707	0.089*
C8	0.5534 (19)	0.0790 (9)	0.4089 (13)	0.054 (4)
H8A	0.5948	0.0246	0.3877	0.08*
H8B	0.4381	0.0775	0.382	0.08*
H8C	0.5906	0.0876	0.4982	0.08*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.0801 (9)	0.0630 (7)	0.0579 (7)	−0.0279 (7)	0.0159 (6)	0.0090 (6)
Cu1	0.0337 (9)	0.0659 (13)	0.0304 (9)	0.0154 (9)	−0.0015 (7)	−0.0125 (9)
O1	0.040 (5)	0.057 (6)	0.032 (5)	0.016 (5)	0.006 (4)	−0.003 (5)
O2	0.030 (6)	0.046 (6)	0.034 (5)	−0.003 (4)	0.004 (4)	−0.012 (5)
N1	0.042 (7)	0.047 (7)	0.021 (6)	0.013 (5)	0.005 (5)	−0.001 (5)
N2	0.033 (6)	0.045 (7)	0.020 (5)	−0.010 (5)	0.005 (5)	−0.001 (5)
C1	0.038 (9)	0.063 (11)	0.046 (9)	0.004 (8)	0.005 (7)	−0.006 (8)
C2	0.050 (9)	0.046 (9)	0.045 (8)	0.003 (8)	0.010 (7)	−0.015 (8)
C3	0.073 (12)	0.062 (11)	0.037 (8)	0.027 (9)	−0.001 (8)	−0.001 (8)
C4	0.048 (9)	0.070 (11)	0.053 (9)	−0.019 (8)	0.035 (8)	−0.008 (8)
C5	0.053 (9)	0.048 (9)	0.032 (8)	0.011 (7)	0.007 (7)	0.005 (7)
C6	0.038 (8)	0.045 (9)	0.030 (7)	0.011 (7)	0.011 (6)	0.014 (6)
C7	0.059 (10)	0.071 (12)	0.042 (9)	0.033 (9)	0.008 (8)	−0.009 (9)
C8	0.081 (12)	0.043 (9)	0.034 (8)	0.000 (8)	0.013 (8)	0.011 (7)

Geometric parameters (Å, º) top

I1—Cu1	2.928 (2)	C2—H2B	0.97
Cu1—O1	2.030 (9)	C3—H3A	0.96
Cu1—N2	2.058 (11)	C3—H3B	0.96
Cu1—N1	2.059 (10)	C3—H3C	0.96
Cu1—O2	2.010 (8)	C4—H4A	0.96
O1—C1	1.399 (16)	C4—H4B	0.96
O2—C5	1.400 (16)	C4—H4C	0.96
O2—H2O	0.82	C5—C6	1.502 (17)
N1—C3	1.466 (15)	C5—H5A	0.97
N1—C2	1.481 (16)	C5—H5B	0.97
N1—C4	1.488 (16)	C6—H6A	0.97
N2—C7	1.465 (16)	C6—H6B	0.97
N2—C8	1.476 (17)	C7—H7A	0.96
N2—C6	1.495 (15)	C7—H7B	0.96
C1—C2	1.512 (19)	C7—H7C	0.96
C1—H1A	0.97	C8—H8A	0.96
C1—H1B	0.97	C8—H8B	0.96
C2—H2A	0.97	C8—H8C	0.96

O1—Cu1—N2	93.9 (4)	N1—C3—H3A	109.5
O1—Cu1—N1	82.2 (4)	N1—C3—H3B	109.5
N2—Cu1—N1	155.4 (4)	H3A—C3—H3B	109.5
O1—Cu1—I1	101.0 (3)	N1—C3—H3C	109.5
N2—Cu1—I1	101.3 (3)	H3A—C3—H3C	109.5
N1—Cu1—I1	103.3 (3)	H3B—C3—H3C	109.5
I1—Cu1—O2	99.6 (3)	N1—C4—H4A	109.5
O1—Cu1—O2	159.5 (4)	N1—C4—H4B	109.5
O2—Cu1—N1	92.9 (4)	H4A—C4—H4B	109.5
O2—Cu1—N2	82.3 (4)	N1—C4—H4C	109.5
C1—O1—Cu1	113.3 (7)	H4A—C4—H4C	109.5
C5—O2—H2O	109.5	H4B—C4—H4C	109.5
C3—N1—C2	110.0 (11)	O2—C5—C6	109.0 (11)
C3—N1—C4	108.1 (11)	O2—C5—H5A	109.9
C2—N1—C4	112.7 (11)	C6—C5—H5A	109.9
C3—N1—Cu1	115.2 (9)	O2—C5—H5B	109.9
C2—N1—Cu1	103.5 (8)	C6—C5—H5B	109.9
C4—N1—Cu1	107.4 (8)	H5A—C5—H5B	108.3
C7—N2—C8	108.0 (11)	N2—C6—C5	109.7 (10)
C7—N2—C6	109.3 (10)	N2—C6—H6A	109.7
C8—N2—C6	111.3 (10)	C5—C6—H6A	109.7
C7—N2—Cu1	115.2 (9)	N2—C6—H6B	109.7
C8—N2—Cu1	109.4 (8)	C5—C6—H6B	109.7
C6—N2—Cu1	103.6 (7)	H6A—C6—H6B	108.2
O1—C1—C2	110.1 (11)	N2—C7—H7A	109.5
O1—C1—H1A	109.6	N2—C7—H7B	109.5
C2—C1—H1A	109.6	H7A—C7—H7B	109.5
O1—C1—H1B	109.6	N2—C7—H7C	109.5
C2—C1—H1B	109.6	H7A—C7—H7C	109.5
H1A—C1—H1B	108.2	H7B—C7—H7C	109.5
N1—C2—C1	108.9 (11)	N2—C8—H8A	109.5
N1—C2—H2A	109.9	N2—C8—H8B	109.5
C1—C2—H2A	109.9	H8A—C8—H8B	109.5
N1—C2—H2B	109.9	N2—C8—H8C	109.5
C1—C2—H2B	109.9	H8A—C8—H8C	109.5
H2A—C2—H2B	108.3	H8B—C8—H8C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O1ⁱ	0.82	1.68	2.482 (12)	167

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	[Cu(C₄H₁₀NO)I(C₄H₁₁NO)]
M_r	367.71
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	8.690 (1), 15.241 (1), 11.116 (1)
β (°)	106.847 (10)
V (Å³)	1409.1 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.72
Crystal size (mm)	0.32 × 0.3 × 0.2

Data collection
Diffractometer	Rigaku AFC-6S
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.333, 0.47
No. of measured, independent and observed [I > 2σ(I)] reflections	2642, 2471, 1003
R_int	0.089
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.204, 1.00
No. of reflections	2471
No. of parameters	133
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.80, −0.83

Computer programs: AFC6S Diffractometer Control Software (Molecular Structure Corporation, 1998), TEXSAN (Molecular Structure Corporation & Rigaku, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Johnson (1976), WinGX (Farrugia, 1999).

Selected bond lengths (Å) top

I1—Cu1	2.928 (2)	Cu1—N1	2.059 (10)
Cu1—O1	2.030 (9)	Cu1—O2	2.010 (8)
Cu1—N2	2.058 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O1ⁱ	0.82	1.68	2.482 (12)	167.3

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Acknowledgements

We thank Professor Philip J. Squattrito for the data collection.

References

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