Unexpected proline coordination in the copper chain polymer [Cu([mu]-Cl)₂([mu]-DL-proline-[kappa]²O:O')]¹_[infinity]

In catena-poly[copper(II)-di-[mu]-chlorido-[mu]-proline-[kappa]²O:O'], [CuCl₂(C₅H₉NO₂)]_n, two symmetry-independent metal cations adopt distorted octa­hedral coordination, typical for d⁹ Jahn-Teller systems. Each chloride bridge is involved in both a short and a very long inter­action with a Cu^II centre. The centrosymmetric crystal structure contains homochiral chains of opposite handedness which extend along the shortest lattice parameter (i.e. a). The O:O'-bridging coor­dination mode of proline, although a common motif for such complexes in general, is remarkable for Cu^II; the vast majority of amino acid derivatives of this cation are characterized by N,O-chelation.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus (Bruker, 2009), TWINABS (Sheldrick, 2008a), CELLNOW (Sheldrick, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008b).

catena-Poly[copper(II)-di-µ-chlorido-µ-proline-κ²O:O']

Crystal data

[CuCl2(C5H9NO2)]	V = 793.2 (3) Å^3
Mr = 249.57	Z = 4
Triclinic, P1	F(000) = 500
a = 6.6312 (14) Å	Dx = 2.090 Mg m^−3
b = 9.717 (2) Å	Mo Kα radiation, λ = 0.71073 Å
c = 12.837 (3) Å	µ = 3.37 mm^−1
α = 76.136 (4)°	T = 100 K
β = 89.521 (4)°	Block, green
γ = 81.162 (4)°	0.14 × 0.12 × 0.06 mm

Data collection

Bruker D8 goniometer with APEX CCD area-detector diffractometer	4741 reflections with I > 2σ(I)
Radiation source: microsource	Rint = 0.075
ω scans	θmax = 26.6°, θmin = 2.2°
Absorption correction: multi-scan (TWINABS; Sheldrick, 2008a)	h = −8→8
Tmin = 0.543, Tmax = 0.745	k = −11→12
15560 measured reflections	l = 0→16
5870 independent reflections

Refinement

Refinement on F^2	4 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.043	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.091	w = 1/[σ^2(Fo^2) + (0.030P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max < 0.001
5870 reflections	Δρmax = 0.59 e Å^−3
212 parameters	Δρmin = −0.45 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. Refined as a two-component twin. Twin law (-1.00007 0.00032 0.00013) (-0.00080 -0.99983 -0.00028) (0.11315 -0.64541 0.99990).

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

	x	y	z	Uiso*/Ueq
Cu1	0.63285 (9)	0.26131 (6)	0.26660 (5)	0.01074 (16)
Cu2	0.14015 (9)	0.23439 (6)	0.22150 (5)	0.01029 (16)
Cl1	−0.04344 (18)	0.44332 (13)	0.13756 (10)	0.0132 (3)
Cl2	0.37357 (19)	0.05382 (13)	0.32052 (10)	0.0139 (3)
Cl3	0.85224 (18)	0.08294 (13)	0.21268 (10)	0.0118 (3)
Cl4	0.45927 (19)	0.45694 (13)	0.30974 (10)	0.0151 (3)
O1	0.5214 (5)	0.3353 (3)	0.1187 (3)	0.0118 (8)
O2	0.2757 (5)	0.2164 (3)	0.0846 (3)	0.0118 (8)
C1	0.4245 (7)	0.2798 (5)	0.0587 (4)	0.0082 (10)
C2	0.4901 (7)	0.3065 (5)	−0.0574 (4)	0.0099 (11)
H2	0.3859	0.3811	−0.1034	0.012*
C3	0.5268 (7)	0.1745 (5)	−0.1043 (4)	0.0116 (11)
H3A	0.4344	0.1054	−0.0731	0.014*
H3B	0.5066	0.2019	−0.1833	0.014*
C4	0.7484 (7)	0.1119 (5)	−0.0721 (4)	0.0139 (11)
H4A	0.7613	0.0573	0.0039	0.017*
H4B	0.8061	0.0478	−0.1180	0.017*
C5	0.8539 (7)	0.2430 (5)	−0.0893 (4)	0.0140 (11)
H5A	0.9733	0.2251	−0.0394	0.017*
H5B	0.9001	0.2699	−0.1640	0.017*
N1	0.6929 (6)	0.3590 (5)	−0.0666 (3)	0.0118 (9)
H1A	0.730 (7)	0.379 (5)	−0.004 (3)	0.014*
H1B	0.680 (7)	0.438 (4)	−0.125 (3)	0.014*
O3	0.0460 (5)	0.2670 (4)	0.3623 (3)	0.0129 (8)
O4	−0.2503 (5)	0.1884 (4)	0.4122 (3)	0.0128 (8)
C6	−0.0738 (8)	0.2116 (5)	0.4300 (4)	0.0110 (11)
C7	0.0005 (7)	0.1744 (5)	0.5463 (4)	0.0118 (11)
H7	−0.0519	0.0864	0.5872	0.014*
C8	−0.0645 (8)	0.3004 (6)	0.5998 (4)	0.0203 (13)
H8A	−0.1209	0.3888	0.5457	0.024*
H8B	−0.1684	0.2770	0.6543	0.024*
C9	0.1325 (8)	0.3189 (6)	0.6521 (4)	0.0195 (13)
H9A	0.1284	0.4192	0.6574	0.023*
H9B	0.1554	0.2544	0.7248	0.023*
C10	0.2963 (8)	0.2794 (5)	0.5779 (4)	0.0156 (12)
H10A	0.2987	0.3579	0.5127	0.019*
H10B	0.4327	0.2552	0.6143	0.019*
N2	0.2300 (7)	0.1508 (5)	0.5519 (3)	0.0119 (9)
H2A	0.280 (7)	0.073 (4)	0.602 (3)	0.014*
H2B	0.282 (7)	0.148 (5)	0.488 (3)	0.014*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0099 (3)	0.0130 (3)	0.0088 (3)	−0.0001 (3)	−0.0014 (3)	−0.0027 (3)
Cu2	0.0090 (3)	0.0116 (3)	0.0093 (3)	−0.0014 (3)	0.0009 (3)	−0.0010 (3)
Cl1	0.0119 (6)	0.0117 (6)	0.0147 (6)	−0.0009 (5)	−0.0011 (5)	−0.0012 (5)
Cl2	0.0108 (6)	0.0142 (6)	0.0148 (6)	−0.0014 (5)	−0.0011 (5)	0.0003 (5)
Cl3	0.0110 (6)	0.0122 (6)	0.0124 (6)	−0.0021 (5)	0.0004 (5)	−0.0034 (5)
Cl4	0.0169 (7)	0.0148 (7)	0.0132 (6)	−0.0002 (5)	0.0015 (5)	−0.0042 (5)
O1	0.0123 (18)	0.0125 (18)	0.0096 (18)	−0.0016 (15)	−0.0003 (15)	−0.0009 (15)
O2	0.0121 (19)	0.0111 (18)	0.0119 (19)	−0.0033 (15)	0.0002 (15)	−0.0018 (15)
C1	0.005 (2)	0.007 (2)	0.012 (3)	0.0016 (19)	−0.001 (2)	−0.001 (2)
C2	0.006 (2)	0.012 (3)	0.012 (3)	−0.002 (2)	−0.002 (2)	−0.002 (2)
C3	0.011 (3)	0.015 (3)	0.011 (3)	−0.002 (2)	0.000 (2)	−0.007 (2)
C4	0.015 (3)	0.012 (3)	0.016 (3)	0.001 (2)	0.003 (2)	−0.006 (2)
C5	0.012 (3)	0.015 (3)	0.016 (3)	0.000 (2)	0.004 (2)	−0.006 (2)
N1	0.015 (2)	0.011 (2)	0.010 (2)	−0.0032 (19)	0.0029 (18)	−0.0020 (18)
O3	0.0142 (19)	0.0121 (19)	0.0118 (19)	−0.0042 (15)	0.0024 (15)	−0.0007 (15)
O4	0.0107 (19)	0.017 (2)	0.0110 (19)	−0.0027 (15)	−0.0022 (15)	−0.0027 (15)
C6	0.016 (3)	0.006 (3)	0.009 (3)	0.006 (2)	−0.002 (2)	−0.004 (2)
C7	0.007 (3)	0.017 (3)	0.009 (3)	−0.002 (2)	−0.001 (2)	0.001 (2)
C8	0.018 (3)	0.030 (3)	0.013 (3)	0.006 (3)	−0.002 (2)	−0.012 (3)
C9	0.022 (3)	0.023 (3)	0.018 (3)	−0.004 (3)	−0.001 (2)	−0.011 (2)
C10	0.015 (3)	0.013 (3)	0.020 (3)	−0.006 (2)	0.000 (2)	−0.003 (2)
N2	0.014 (2)	0.012 (2)	0.009 (2)	−0.0015 (19)	−0.0020 (18)	−0.0012 (19)

Geometric parameters (Å, º)

Cu1—O1	1.968 (3)	C5—N1	1.509 (6)
Cu1—O4^i	1.953 (3)	C5—H5A	0.9900
Cu1—Cl4	2.2510 (14)	C5—H5B	0.9900
Cu1—Cl3	2.3201 (14)	N1—H1A	0.92 (2)
Cu2—O3	1.988 (3)	N1—H1B	0.93 (2)
Cu2—O2	1.999 (3)	O3—C6	1.254 (6)
Cu2—Cl1	2.2314 (14)	O4—C6	1.258 (6)
Cu2—Cl2	2.2847 (14)	O4—Cu1^ii	1.953 (3)
Cu2—Cl3^ii	2.6020 (14)	C6—C7	1.516 (6)
Cu2—Cl4	3.6136 (15)	C7—N2	1.504 (6)
Cl3—Cu2^i	2.6020 (14)	C7—C8	1.547 (7)
O1—C1	1.269 (5)	C7—H7	1.0000
O2—C1	1.244 (5)	C8—C9	1.528 (7)
C1—C2	1.523 (7)	C8—H8A	0.9900
C2—N1	1.504 (6)	C8—H8B	0.9900
C2—C3	1.529 (6)	C9—C10	1.504 (7)
C2—H2	1.0000	C9—H9A	0.9900
C3—C4	1.522 (6)	C9—H9B	0.9900
C3—H3A	0.9900	C10—N2	1.496 (6)
C3—H3B	0.9900	C10—H10A	0.9900
C4—C5	1.516 (7)	C10—H10B	0.9900
C4—H4A	0.9900	N2—H2A	0.89 (2)
C4—H4B	0.9900	N2—H2B	0.90 (2)
O4^i—Cu1—O1	178.69 (14)	N1—C5—H5A	110.9
O4^i—Cu1—Cl4	91.42 (11)	C4—C5—H5A	110.9
O1—Cu1—Cl4	89.11 (10)	N1—C5—H5B	110.9
O4^i—Cu1—Cl3	89.29 (11)	C4—C5—H5B	110.9
O1—Cu1—Cl3	89.99 (10)	H5A—C5—H5B	108.9
Cl4—Cu1—Cl3	170.66 (5)	C2—N1—C5	109.0 (4)
O3—Cu2—O2	170.29 (14)	C2—N1—H1A	111 (3)
O3—Cu2—Cl1	90.19 (11)	C5—N1—H1A	108 (3)
O2—Cu2—Cl1	90.55 (10)	C2—N1—H1B	106 (3)
O3—Cu2—Cl2	85.29 (10)	C5—N1—H1B	109 (3)
O2—Cu2—Cl2	91.85 (10)	H1A—N1—H1B	114 (4)
Cl1—Cu2—Cl2	166.68 (5)	C6—O3—Cu2	133.8 (3)
O3—Cu2—Cl3^ii	91.17 (10)	C6—O4—Cu1^ii	118.1 (3)
O2—Cu2—Cl3^ii	98.41 (10)	O3—C6—O4	127.1 (5)
Cl1—Cu2—Cl3^ii	95.12 (5)	O3—C6—C7	115.9 (4)
Cl2—Cu2—Cl3^ii	97.48 (5)	O4—C6—C7	117.0 (4)
O3—Cu2—Cl4	70.85 (10)	N2—C7—C6	109.7 (4)
O2—Cu2—Cl4	99.60 (10)	N2—C7—C8	104.8 (4)
Cl1—Cu2—Cl4	84.23 (4)	C6—C7—C8	111.6 (4)
Cl2—Cu2—Cl4	82.45 (4)	N2—C7—H7	110.2
Cl3^ii—Cu2—Cl4	161.99 (4)	C6—C7—H7	110.2
Cu1—Cl3—Cu2^i	86.85 (5)	C8—C7—H7	110.2
Cu1—Cl4—Cu2	65.76 (4)	C9—C8—C7	104.3 (4)
C1—O1—Cu1	131.9 (3)	C9—C8—H8A	110.9
C1—O2—Cu2	117.8 (3)	C7—C8—H8A	110.9
O2—C1—O1	126.0 (5)	C9—C8—H8B	110.9
O2—C1—C2	118.7 (4)	C7—C8—H8B	110.9
O1—C1—C2	115.0 (4)	H8A—C8—H8B	108.9
N1—C2—C1	109.8 (4)	C10—C9—C8	104.1 (4)
N1—C2—C3	103.7 (4)	C10—C9—H9A	110.9
C1—C2—C3	115.7 (4)	C8—C9—H9A	110.9
N1—C2—H2	109.1	C10—C9—H9B	110.9
C1—C2—H2	109.1	C8—C9—H9B	110.9
C3—C2—H2	109.1	H9A—C9—H9B	109.0
C4—C3—C2	103.2 (4)	N2—C10—C9	101.6 (4)
C4—C3—H3A	111.1	N2—C10—H10A	111.4
C2—C3—H3A	111.1	C9—C10—H10A	111.4
C4—C3—H3B	111.1	N2—C10—H10B	111.4
C2—C3—H3B	111.1	C9—C10—H10B	111.4
H3A—C3—H3B	109.1	H10A—C10—H10B	109.3
C5—C4—C3	103.6 (4)	C10—N2—C7	107.9 (4)
C5—C4—H4A	111.0	C10—N2—H2A	109 (3)
C3—C4—H4A	111.0	C7—N2—H2A	112 (3)
C5—C4—H4B	111.0	C10—N2—H2B	105 (3)
C3—C4—H4B	111.0	C7—N2—H2B	111 (3)
H4A—C4—H4B	109.0	H2A—N2—H2B	112 (4)
N1—C5—C4	104.4 (4)

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