[(6R,7S,8S,14R)-(–)-α-Isosparteine-κ²N,N′]­bis­(nitrito-κ²O,O′)copper(II)

In the title complex, [Cu(NO₂)₂(α-C₁₅H₂₆N₂)], chiral (6R,7S,8S,14R)-(−)-α-isosparteine acts as a bidentate ligand, with two nitrite ligands occupying the remaining coordination sites as η²-chelating groups, producing a pseudo-octahedral coordination complex. The mol­ecule of the title complex possesses a crystallographic twofold axis of rotation along a line through the central C atom of the (−)-α-isosparteine ligand and the Cu^II atom. However, as a result of the Jahn–Teller effect operating on the d⁹ configuration of the copper(II) ion, each nitrite ligand coordinates asymmetrically to the copper(II) centre in a bidentate fashion.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.040
• wR factor = 0.083
• Data-to-parameter ratio = 16.3

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT052_ALERT_1_A (Proper) Absorption Correction Method Missing ..          ?

Alert level C
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors  for        O2A
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors  for         Cu
PLAT301_ALERT_3_C Main Residue  Disorder .........................       8.00 Perc.
PLAT779_ALERT_2_C Suspect or Irrelevant (Bond) Angle in CIF ......      12.00 Deg.
              O2A  -N2   -O2      1.555   1.555   1.555

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.48
           From the CIF: _reflns_number_total               1956
           Count of symmetry unique reflns         1219
           Completeness (_total/calc)            160.46%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       737
           Fraction of Friedel pairs measured     0.605
           Are heavy atom types Z>Si present          yes

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

   1 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
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 EXPRESS (Enraf Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

[(6R,7S,8S,14R)-(-)-α-Isosparteine-κ²N,N']bis(nitrito-κ²O,O')copper(II)

Crystal data

[Cu(NO2)2(C15H26N2)]	Dx = 1.519 Mg m^−3
Mr = 389.94	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P41212	Cell parameters from 22 reflections
Hall symbol: P 4abw 2nw	θ = 11.4–14.1°
a = 8.2446 (5) Å	µ = 1.31 mm^−1
c = 25.088 (4) Å	T = 293 K
V = 1705.3 (3) Å^3	Block, dark green
Z = 4	0.30 × 0.23 × 0.23 mm
F(000) = 820

Data collection

Enraf–Nonius CAD-4 diffractometer	1445 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.061
Graphite monochromator	θmax = 27.5°, θmin = 2.6°
non–profiled ω/2θ scans	h = −10→10
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
Tmin = 0.622, Tmax = 0.730	l = 0→32
4231 measured reflections	3 standard reflections every 400 reflections
1956 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.040	H-atom parameters constrained
wR(F^2) = 0.083	w = 1/[σ^2(Fo^2) + (0.0297P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max < 0.001
1956 reflections	Δρmax = 0.44 e Å^−3
120 parameters	Δρmin = −0.23 e Å^−3
0 restraints	Absolute structure: Flack (1983), 737 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.01 (2)

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	Occ. (<1)
Cu	0.22073 (5)	0.22073 (5)	0.0000	0.03224 (16)
N1	−0.0235 (3)	0.2150 (3)	0.01373 (9)	0.0301 (6)
N2	0.4899 (5)	0.2616 (5)	0.05914 (17)	0.0661 (11)
O1	0.4632 (3)	0.2331 (4)	0.01043 (11)	0.0618 (8)
O2	0.360 (5)	0.247 (8)	0.0882 (13)	0.072 (6)	0.5 (2)
O2A	0.375 (6)	0.278 (11)	0.0838 (18)	0.075 (9)	0.5 (2)
C2	−0.0917 (5)	0.3801 (4)	0.02421 (13)	0.0403 (9)
H2A	−0.2092	0.3735	0.0249	0.048*
H2B	−0.0611	0.4521	−0.0047	0.048*
C3	−0.0326 (5)	0.4506 (4)	0.07654 (14)	0.0479 (10)
H3A	0.0839	0.4666	0.0748	0.058*
H3B	−0.0829	0.5555	0.0823	0.058*
C4	−0.0726 (5)	0.3395 (5)	0.12285 (14)	0.0497 (10)
H4A	−0.1892	0.3354	0.1279	0.060*
H4B	−0.0242	0.3817	0.1552	0.060*
C5	−0.0085 (5)	0.1698 (4)	0.11210 (13)	0.0421 (9)
H5A	−0.0423	0.0977	0.1406	0.051*
H5B	0.1092	0.1720	0.1115	0.051*
C6	−0.0712 (4)	0.1056 (4)	0.05904 (12)	0.0329 (8)
H6	−0.1898	0.1089	0.0611	0.039*
C8	−0.1002 (4)	0.1528 (4)	−0.03672 (13)	0.0365 (9)
H8A	−0.0590	0.2152	−0.0666	0.044*
H8B	−0.2163	0.1707	−0.0348	0.044*
C7	−0.0696 (4)	−0.0255 (4)	−0.04733 (13)	0.0361 (8)
H7	−0.1348	−0.0567	−0.0783	0.043*
C9	−0.1272 (4)	−0.1272 (4)	0.0000	0.0425 (12)
H9	−0.2418	−0.1095	0.0066	0.051*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu	0.03328 (19)	0.03328 (19)	0.0302 (3)	−0.0058 (2)	0.00386 (19)	−0.00386 (19)
N1	0.0341 (15)	0.0299 (13)	0.0264 (13)	0.0022 (13)	−0.0009 (10)	−0.0004 (13)
N2	0.044 (2)	0.081 (3)	0.073 (3)	−0.008 (2)	−0.005 (2)	−0.019 (2)
O1	0.0424 (16)	0.083 (2)	0.0602 (18)	−0.0096 (14)	0.0009 (13)	−0.0262 (18)
O2	0.056 (9)	0.098 (14)	0.061 (10)	−0.013 (12)	0.015 (9)	0.009 (10)
O2A	0.059 (8)	0.12 (2)	0.042 (9)	−0.037 (13)	−0.006 (8)	−0.012 (11)
C2	0.048 (2)	0.033 (2)	0.041 (2)	0.0057 (17)	0.0031 (17)	−0.0038 (16)
C3	0.057 (3)	0.042 (2)	0.045 (2)	0.0044 (18)	0.0098 (19)	−0.0112 (18)
C4	0.054 (3)	0.062 (3)	0.0335 (19)	0.0007 (19)	0.0068 (19)	−0.0166 (18)
C5	0.045 (2)	0.054 (3)	0.0275 (17)	0.0003 (17)	0.0052 (16)	0.0014 (16)
C6	0.0271 (18)	0.044 (2)	0.0272 (16)	−0.0026 (15)	0.0035 (14)	0.0013 (15)
C8	0.035 (2)	0.045 (2)	0.0291 (17)	0.0063 (17)	−0.0065 (15)	−0.0014 (15)
C7	0.037 (2)	0.038 (2)	0.0338 (17)	−0.0040 (16)	−0.0063 (14)	−0.0048 (15)
C9	0.0396 (17)	0.0396 (17)	0.048 (3)	−0.012 (2)	0.004 (2)	−0.004 (2)

Geometric parameters (Å, º)

Cu—N1	2.043 (3)	C3—H3B	0.9700
Cu—N1^i	2.043 (3)	C4—C5	1.520 (5)
Cu—O1	2.019 (3)	C4—H4A	0.9700
Cu—O1^i	2.019 (3)	C4—H4B	0.9700
Cu—O2	2.50 (3)	C5—C6	1.523 (4)
Cu—O2^i	2.50 (3)	C5—H5A	0.9700
N1—C2	1.496 (4)	C5—H5B	0.9700
N1—C6	1.503 (4)	C6—C7^i	1.521 (4)
N1—C8	1.505 (4)	C6—H6	0.9800
N2—O2A	1.14 (5)	C8—C7	1.515 (4)
N2—O1	1.264 (4)	C8—H8A	0.9700
N2—O2	1.30 (5)	C8—H8B	0.9700
C2—C3	1.517 (5)	C7—C6^i	1.521 (4)
C2—H2A	0.9700	C7—C9	1.529 (4)
C2—H2B	0.9700	C7—H7	0.9800
C3—C4	1.516 (5)	C9—C7^i	1.529 (4)
C3—H3A	0.9700	C9—H9	0.9700
N1—Cu—N1^i	89.01 (16)	C2—C3—H3B	109.4
N1—Cu—O1	162.78 (9)	H3A—C3—H3B	108.0
N1—Cu—O1^i	95.43 (12)	C3—C4—C5	110.1 (3)
N1—Cu—O2	107.8 (11)	C3—C4—H4A	109.6
N1—Cu—O2^i	104.2 (14)	C5—C4—H4A	109.6
O1—Cu—N1^i	95.43 (12)	C3—C4—H4B	109.6
O1—Cu—O1^i	85.23 (18)	C5—C4—H4B	109.6
O1—Cu—O2	55.0 (11)	H4A—C4—H4B	108.1
O1—Cu—O2^i	90.3 (15)	C4—C5—C6	110.9 (3)
O2—Cu—N1^i	104.2 (14)	C4—C5—H5A	109.5
O2—Cu—O1^i	90.3 (15)	C6—C5—H5A	109.5
O2—Cu—O2^i	135 (3)	C4—C5—H5B	109.5
N1^i—Cu—O1^i	162.78 (9)	C6—C5—H5B	109.5
N1^i—Cu—O2^i	107.8 (11)	H5A—C5—H5B	108.0
O1^i—Cu—O2^i	55.0 (11)	N1—C6—C7^i	111.0 (2)
C2—N1—C6	108.3 (2)	N1—C6—C5	111.3 (3)
C2—N1—C8	107.4 (2)	C7^i—C6—C5	114.5 (3)
C6—N1—C8	108.8 (3)	N1—C6—H6	106.5
C2—N1—Cu	112.3 (2)	C7^i—C6—H6	106.5
C6—N1—Cu	113.52 (18)	C5—C6—H6	106.5
C8—N1—Cu	106.28 (19)	N1—C8—C7	114.1 (3)
O2A—N2—O1	113.9 (11)	N1—C8—H8A	108.7
O2A—N2—O2	12 (5)	C7—C8—H8A	108.7
O1—N2—O2	112.4 (13)	N1—C8—H8B	108.7
N2—O1—Cu	107.9 (2)	C7—C8—H8B	108.7
N2—O2—Cu	83.7 (14)	H8A—C8—H8B	107.6
N1—C2—C3	112.3 (3)	C8—C7—C6^i	115.6 (3)
N1—C2—H2A	109.1	C8—C7—C9	110.1 (2)
C3—C2—H2A	109.1	C6^i—C7—C9	108.0 (2)
N1—C2—H2B	109.1	C8—C7—H7	107.6
C3—C2—H2B	109.1	C6^i—C7—H7	107.6
H2A—C2—H2B	107.9	C9—C7—H7	107.6
C4—C3—C2	111.2 (3)	C7^i—C9—C7	105.2 (3)
C4—C3—H3A	109.4	C7^i—C9—H9	110.7
C2—C3—H3A	109.4	C7—C9—H9	110.7
C4—C3—H3B	109.4

Symmetry code: (i) y, x, −z.