2,2′-Bipyridinium 1-oxide triiodide

The title compound, C₁₀H₉N₂O⁺·I₃⁻, was obtained unintentionally as the product of an attempted synthesis of an iodo­plumbate complex using NaI as a donor to provide I⁻. The cation is planar (r.m.s. deviation for all non-H atoms is 0.024 Å) and has an intramolecular N—H...O hydrogen bond.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.010 Å
• R factor = 0.039
• wR factor = 0.090
• Data-to-parameter ratio = 23.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.89
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       1.88
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         I1
PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...         10

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      1.875
            Tmax scaled      0.469 Tmin scaled      0.263
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 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

The three I atoms of the I₃^- anion are almost linear with an I2—I1—I3 angle of 178.89 (2)°. The protonated 2,2'-bipyridine-N-oxide molecule is planar (r.m.s. deviation for all non-H atoms 0.024 Å). The molecular conformation of the cation is stabilized by an N—H···O hydrogen bond.

Related literature

For related literature, see: Corey et al. (1965).

S2. Experimental

2,2'-bipyridine-N-oxide was prepared as reported in literature (Corey et al., 1965). The title compound was obtained unintentionally as the product of an attempted synthesis of a iodoplumbate complex. 2,2'-bipyridine-N-oxide (0.17 g, 1.0 mmol) and Pb(NO₃)₂ (0.33 g, 1 mmol) were dissolved in 15 ml DMSO and stirred for 2 h, then addition NaI^.2H₂O (0.55 g, 3 mmol) with continuous stirring for 2 h at room temperature. Finally, a clear yellow solution was obtained and adjusted to pH=4.0 using 10% HNO₃/DMSO, which was allowed to evaporate at room temperature. Blue block-like crystals formed over two weeks.

S3. Refinement

All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 Å and N—H = 0.86 Å and with U_iso(H) = 1.2Ueq(C,N).

Computing details

Data collection: TEXRAY (Molecular Structure Corporation, 1999); cell refinement: TEXRAY (Molecular Structure Corporation, 1999); data reduction: TEXSAN (Molecular Structure Corporation, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SORTX (McArdle, 1995); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

Fig. 1. The structure of the title compound showing the atom numbering scheme with ellipsoids drawn at the 50% probability level.

2,2'-Bipyridinium 1-oxide triiodide

Crystal data

C10H9N2O^+·I3^−	F(000) = 1000
Mr = 553.89	Dx = 2.484 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P2ybc	Cell parameters from 25 reflections
a = 7.9714 (16) Å	θ = 12–18°
b = 12.045 (2) Å	µ = 6.31 mm^−1
c = 15.434 (3) Å	T = 293 K
β = 91.44 (3)°	Cube, blue
V = 1481.4 (5) Å^3	0.20 × 0.15 × 0.12 mm
Z = 4

Data collection

Rigaku Weissenberg IP diffractometer	3393 independent reflections
Radiation source: rotor target	2116 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.041
Detector resolution: None pixels mm^-1	θmax = 27.5°, θmin = 3.1°
ω scans	h = −10→10
Absorption correction: multi-scan (TEXRAY; Molecular Structure Corporation, 1999)	k = −15→15
Tmin = 0.14, Tmax = 0.250	l = −20→20
13781 measured reflections

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)] = 0.039	H-atom parameters constrained
wR(F^2) = 0.090	w = 1/[σ^2(Fo^2) + (0.0369P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max < 0.001
3393 reflections	Δρmax = 0.80 e Å^−3
146 parameters	Δρmin = −0.75 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0010 (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
I1	0.27866 (5)	0.31326 (4)	0.13335 (3)	0.07513 (17)
I2	0.41434 (6)	0.48743 (5)	0.24785 (3)	0.0888 (2)
I3	0.14733 (7)	0.14252 (5)	0.01697 (4)	0.1009 (2)
N1	0.8457 (5)	0.3845 (4)	0.2042 (3)	0.0575 (11)
O1	0.8225 (5)	0.2820 (3)	0.2317 (2)	0.0704 (11)
N2	0.7180 (6)	0.2285 (4)	0.0877 (3)	0.0588 (11)
H2	0.7394	0.2144	0.1415	0.071*
C1	0.9078 (7)	0.4603 (6)	0.2609 (4)	0.0728 (17)
H1	0.9334	0.4388	0.3175	0.087*
C2	0.9336 (9)	0.5660 (6)	0.2373 (5)	0.088 (2)
H2A	0.9770	0.6164	0.2777	0.106*
C3	0.8969 (10)	0.6006 (6)	0.1549 (6)	0.095 (2)
H3	0.9159	0.6736	0.1381	0.114*
C4	0.8312 (9)	0.5244 (5)	0.0974 (4)	0.0767 (17)
H4	0.8023	0.5472	0.0414	0.092*
C5	0.8065 (7)	0.4149 (5)	0.1202 (3)	0.0575 (13)
C6	0.7418 (7)	0.3317 (5)	0.0591 (3)	0.0573 (13)
C7	0.7041 (9)	0.3532 (6)	−0.0261 (4)	0.0774 (18)
H7	0.7169	0.4246	−0.0479	0.093*
C8	0.6471 (9)	0.2690 (8)	−0.0799 (4)	0.091 (2)
H8	0.6225	0.2834	−0.1380	0.109*
C9	0.6267 (9)	0.1642 (7)	−0.0472 (5)	0.090 (2)
H9	0.5887	0.1066	−0.0828	0.108*
C10	0.6627 (8)	0.1462 (5)	0.0369 (4)	0.0740 (17)
H10	0.6489	0.0756	0.0600	0.089*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
I1	0.0627 (3)	0.0830 (3)	0.0804 (3)	0.0191 (2)	0.01698 (19)	0.0211 (2)
I2	0.0840 (3)	0.1103 (4)	0.0719 (3)	0.0224 (3)	−0.0012 (2)	0.0038 (2)
I3	0.0921 (4)	0.0977 (4)	0.1132 (4)	0.0065 (3)	0.0090 (3)	−0.0074 (3)
N1	0.057 (3)	0.055 (3)	0.061 (3)	0.005 (2)	0.007 (2)	−0.004 (2)
O1	0.096 (3)	0.056 (2)	0.060 (2)	0.003 (2)	−0.004 (2)	0.0055 (19)
N2	0.064 (3)	0.058 (3)	0.054 (3)	0.005 (2)	0.006 (2)	0.004 (2)
C1	0.072 (4)	0.077 (5)	0.070 (4)	−0.004 (3)	−0.005 (3)	−0.018 (3)
C2	0.084 (5)	0.067 (5)	0.115 (6)	−0.018 (4)	0.012 (4)	−0.033 (4)
C3	0.107 (6)	0.059 (4)	0.120 (6)	−0.015 (4)	0.022 (5)	0.006 (4)
C4	0.089 (5)	0.062 (4)	0.079 (4)	−0.004 (3)	0.010 (3)	0.009 (3)
C5	0.056 (3)	0.055 (3)	0.061 (3)	0.002 (3)	0.009 (2)	0.002 (3)
C6	0.054 (3)	0.064 (4)	0.055 (3)	0.007 (3)	0.011 (2)	0.006 (3)
C7	0.099 (5)	0.078 (4)	0.055 (3)	0.006 (4)	0.006 (3)	0.009 (3)
C8	0.105 (6)	0.116 (6)	0.050 (4)	0.001 (5)	−0.006 (3)	−0.006 (4)
C9	0.096 (5)	0.098 (6)	0.075 (5)	−0.016 (4)	0.000 (4)	−0.030 (4)
C10	0.087 (5)	0.063 (4)	0.072 (4)	−0.013 (3)	0.006 (3)	−0.018 (3)

Geometric parameters (Å, º)

I1—I3	2.9080 (9)	C3—C4	1.371 (10)
I1—I2	2.9322 (9)	C3—H3	0.9300
N1—O1	1.320 (6)	C4—C5	1.380 (8)
N1—O1	1.320 (6)	C4—H4	0.9300
N1—C1	1.349 (7)	C5—C6	1.461 (8)
N1—C5	1.377 (7)	C6—C7	1.366 (8)
N2—C10	1.332 (7)	C7—C8	1.379 (9)
N2—C6	1.334 (7)	C7—H7	0.9300
N2—H2	0.8600	C8—C9	1.371 (10)
C1—C2	1.341 (9)	C8—H8	0.9300
C1—H1	0.9300	C9—C10	1.340 (9)
C2—C3	1.364 (10)	C9—H9	0.9300
C2—H2A	0.9300	C10—H10	0.9300
I3—I1—I2	178.89 (2)	C5—C4—H4	119.0
O1—N1—C1	118.5 (5)	N1—C5—C4	117.6 (5)
O1—N1—C1	118.5 (5)	N1—C5—C6	119.6 (5)
O1—N1—C5	121.4 (4)	C4—C5—C6	122.8 (5)
O1—N1—C5	121.4 (4)	N2—C6—C7	117.8 (6)
C1—N1—C5	120.1 (5)	N2—C6—C5	118.4 (5)
C10—N2—C6	123.0 (5)	C7—C6—C5	123.8 (6)
C10—N2—H2	118.5	C6—C7—C8	120.1 (6)
C6—N2—H2	118.5	C6—C7—H7	120.0
C2—C1—N1	121.6 (6)	C8—C7—H7	120.0
C2—C1—H1	119.2	C9—C8—C7	119.7 (6)
N1—C1—H1	119.2	C9—C8—H8	120.1
C1—C2—C3	120.8 (7)	C7—C8—H8	120.1
C1—C2—H2A	119.6	C10—C9—C8	118.7 (6)
C3—C2—H2A	119.6	C10—C9—H9	120.7
C2—C3—C4	118.0 (7)	C8—C9—H9	120.7
C2—C3—H3	121.0	N2—C10—C9	120.7 (6)
C4—C3—H3	121.0	N2—C10—H10	119.7
C3—C4—C5	122.0 (6)	C9—C10—H10	119.7
C3—C4—H4	119.0

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O1	0.86	1.73	2.439 (6)	138