Bis[4-(dimethyl­amino)pyridinium] tetra­bromidodiphenyl­stannate(IV)

The Sn^IV atom of the stannate anion in the title salt, (C₇H₁₁N₂)₂[SnBr₄(C₆H₅)₂], lies on a center of inversion in a tetra­gonally compressed octa­hedron. The two independent Br atoms in the anion are hydrogen-bond acceptors for the same cation.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.024
• wR factor = 0.052
• Data-to-parameter ratio = 20.1

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.386     0.514
            Tmin and Tmax expected:      0.264     0.464
            RR =      1.321
            Please check that your absorption correction is appropriate.
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT060_ALERT_3_C Ratio Tmax/Tmin (Exp-to-Rep) (too) Large .......       1.34
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.90
PLAT716_ALERT_1_C H...A   Unknown or Inconsistent Label ..........    H2<I>N<
PLAT716_ALERT_1_C H...A   Unknown or Inconsistent Label ..........    H2<I>N<
PLAT731_ALERT_1_C Bond    Calc     0.88(3), Rep   0.879(10) ......       3.00 su-Ra
              N2   -H2N     1.555   1.555

Alert level G
FORMU01_ALERT_1_G  There is a discrepancy between the atom counts in the
            _chemical_formula_sum and _chemical_formula_moiety. This is
            usually due to the moiety formula being in the wrong format.
            Atom count from _chemical_formula_sum:   C26 H32 Br4 N4 Sn1
            Atom count from _chemical_formula_moiety:C26 H32 Br4 N2 Sn1
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      0.903
            Tmax scaled      0.464 Tmin scaled      0.348
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
   7 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   5 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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

Bis[4-(dimethylamino)pyridinium] tetrabromidodiphenylstannate(IV), (I) (Fig. 1 and Table 1) was the product of the cleavage of the mixed alkyl/triarylstannate, cyclopentyltriphenyltin, by 4-dimethylaminopyridine hydrobromide perbromide. The stannate has the tin atom in a tetragonally compressed octahedral Br₄C₂ environment. The anion has also been reported as the centrosymmetric pyridinium salt: Sn–Br = 2.7592 (3), 2.7737 (3) and Sn–C 2.158 (3) Å (Tuleda & Khan, 1991). Connections between ions are of the type N-H···Br (Table 2) so that each independent pair of bromide atoms are linked to the same cation.

Related literature

For the structure of dipyridinium tetrabromidostannate, see: Tuleda & Khan (1991).

S2. Experimental

Cyclopentyltriphenyltin (1.36 g, 3 mmol) and 4-dimethylaminopyridine hydrobromide perbromide (1.1 g, 3 mmol) were heated in chloroform (100 ml) for 3 h. The filtered solution when allowed to evaporate yielded large yellow crystals, m.p. 470–473 K.

S3. Refinement

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 0.98 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2 to 1.5U_eq(C). The ammonium H atom was refined with a distance restraint of N–H 0.88±0.01 Å; its displacement parameter was freely refined.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) plot of [C7H11N]2 [SnBr4(C6H5)2] at the 70% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.

Bis[4-(dimethylamino)pyridinium] tetrabromidodiphenylstannate(IV)

Crystal data

(C7H11N2)2[SnBr4(C6H5)2]	F(000) = 812
Mr = 838.89	Dx = 1.916 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3449 reflections
a = 10.7803 (2) Å	θ = 2.3–28.3°
b = 9.3847 (2) Å	µ = 6.40 mm^−1
c = 14.4068 (4) Å	T = 100 K
β = 94.126 (2)°	Block, colorless
V = 1453.76 (6) Å^3	0.24 × 0.18 × 0.12 mm
Z = 2

Data collection

Bruker SMART APEX diffractometer	3334 independent reflections
Radiation source: fine-focus sealed tube	2688 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ω scans	θmax = 27.5°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→14
Tmin = 0.386, Tmax = 0.514	k = −12→12
11853 measured reflections	l = −18→14

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.051	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0228P)^2] where P = (Fo^2 + 2Fc^2)/3
3334 reflections	(Δ/σ)max = 0.001
166 parameters	Δρmax = 0.47 e Å^−3
1 restraint	Δρmin = −0.42 e Å^−3

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

	x	y	z	Uiso*/Ueq
Sn1	0.5000	0.5000	0.5000	0.01159 (7)
Br1	0.25635 (2)	0.50711 (3)	0.43147 (2)	0.01591 (7)
Br2	0.55014 (2)	0.71661 (3)	0.38004 (2)	0.01549 (7)
N1	0.05057 (19)	1.2090 (2)	0.45413 (16)	0.0168 (5)
N2	0.2527 (2)	0.8608 (3)	0.3851 (2)	0.0309 (7)
H2N	0.296 (3)	0.785 (2)	0.372 (3)	0.057 (12)*
C1	0.4622 (2)	0.6546 (3)	0.60374 (19)	0.0130 (6)
C2	0.5344 (2)	0.7784 (3)	0.6151 (2)	0.0185 (6)
H2	0.6043	0.7916	0.5794	0.022*
C3	0.5038 (3)	0.8816 (3)	0.6784 (2)	0.0232 (7)
H3	0.5529	0.9654	0.6862	0.028*
C4	0.4025 (3)	0.8631 (3)	0.7301 (2)	0.0248 (7)
H4	0.3807	0.9354	0.7722	0.030*
C5	0.3325 (3)	0.7406 (3)	0.7212 (2)	0.0219 (7)
H5	0.2639	0.7277	0.7582	0.026*
C6	0.3615 (2)	0.6360 (3)	0.65865 (19)	0.0172 (6)
H6	0.3131	0.5515	0.6530	0.021*
C7	−0.0284 (3)	1.2845 (3)	0.3844 (2)	0.0260 (7)
H7A	0.0236	1.3368	0.3429	0.039*
H7B	−0.0816	1.3517	0.4153	0.039*
H7C	−0.0804	1.2160	0.3481	0.039*
C8	0.0588 (3)	1.2631 (3)	0.5493 (2)	0.0209 (6)
H8A	0.0386	1.1866	0.5920	0.031*
H8B	−0.0001	1.3418	0.5541	0.031*
H8C	0.1435	1.2972	0.5657	0.031*
C9	0.1188 (2)	1.0979 (3)	0.4305 (2)	0.0141 (6)
C10	0.1155 (2)	1.0461 (3)	0.3381 (2)	0.0182 (6)
H10	0.0668	1.0937	0.2900	0.022*
C11	0.1821 (3)	0.9282 (3)	0.3182 (2)	0.0254 (7)
H11	0.1786	0.8932	0.2562	0.031*
C12	0.2617 (3)	0.9093 (3)	0.4731 (2)	0.0280 (8)
H12	0.3141	0.8609	0.5186	0.034*
C13	0.1979 (2)	1.0250 (3)	0.4982 (2)	0.0201 (7)
H13	0.2058	1.0577	0.5607	0.024*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sn1	0.01150 (12)	0.01286 (14)	0.01055 (14)	0.00047 (10)	0.00166 (10)	0.00068 (11)
Br1	0.01193 (13)	0.01943 (15)	0.01628 (15)	0.00059 (10)	0.00046 (10)	0.00031 (12)
Br2	0.01807 (13)	0.01534 (14)	0.01326 (14)	−0.00163 (11)	0.00254 (10)	0.00332 (13)
N1	0.0165 (11)	0.0180 (12)	0.0155 (13)	0.0016 (10)	−0.0018 (9)	0.0031 (11)
N2	0.0372 (15)	0.0258 (16)	0.0305 (17)	0.0166 (13)	0.0093 (13)	0.0049 (14)
C1	0.0147 (13)	0.0135 (14)	0.0109 (15)	0.0026 (11)	0.0011 (11)	−0.0007 (12)
C2	0.0209 (14)	0.0194 (15)	0.0155 (15)	−0.0009 (12)	0.0027 (12)	0.0045 (13)
C3	0.0308 (16)	0.0152 (16)	0.0227 (17)	−0.0012 (12)	−0.0039 (13)	−0.0025 (13)
C4	0.0339 (17)	0.0243 (17)	0.0158 (16)	0.0109 (14)	−0.0004 (13)	−0.0078 (14)
C5	0.0193 (14)	0.0345 (19)	0.0120 (15)	0.0065 (12)	0.0012 (12)	−0.0018 (14)
C6	0.0139 (13)	0.0235 (16)	0.0138 (15)	0.0001 (11)	−0.0015 (11)	−0.0003 (13)
C7	0.0217 (15)	0.0307 (18)	0.0244 (17)	0.0081 (13)	−0.0072 (13)	−0.0020 (15)
C8	0.0233 (14)	0.0217 (16)	0.0178 (16)	−0.0016 (12)	0.0018 (12)	−0.0022 (13)
C9	0.0132 (12)	0.0147 (14)	0.0147 (15)	−0.0048 (10)	0.0016 (11)	0.0038 (12)
C10	0.0184 (14)	0.0163 (15)	0.0197 (16)	0.0006 (11)	0.0000 (12)	0.0056 (13)
C11	0.0345 (17)	0.0237 (17)	0.0188 (17)	0.0052 (14)	0.0073 (14)	0.0021 (15)
C12	0.0271 (16)	0.0303 (19)	0.0261 (19)	0.0057 (14)	−0.0014 (14)	0.0102 (16)
C13	0.0192 (13)	0.0234 (17)	0.0175 (16)	−0.0012 (12)	0.0010 (12)	0.0045 (13)

Geometric parameters (Å, º)

Sn1—C1	2.143 (3)	C4—H4	0.9500
Sn1—C1^i	2.143 (3)	C5—C6	1.384 (4)
Sn1—Br1	2.7395 (2)	C5—H5	0.9500
Sn1—Br1^i	2.7395 (2)	C6—H6	0.9500
Sn1—Br2	2.7470 (3)	C7—H7A	0.9800
Sn1—Br2^i	2.7470 (3)	C7—H7B	0.9800
N1—C9	1.334 (3)	C7—H7C	0.9800
N1—C7	1.454 (3)	C8—H8A	0.9800
N1—C8	1.459 (4)	C8—H8B	0.9800
N2—C12	1.344 (4)	C8—H8C	0.9800
N2—C11	1.342 (4)	C9—C10	1.415 (4)
N2—H2N	0.879 (10)	C9—C13	1.424 (4)
C1—C6	1.399 (4)	C10—C11	1.361 (4)
C1—C2	1.402 (4)	C10—H10	0.9500
C2—C3	1.387 (4)	C11—H11	0.9500
C2—H2	0.9500	C12—C13	1.349 (4)
C3—C4	1.376 (4)	C12—H12	0.9500
C3—H3	0.9500	C13—H13	0.9500
C4—C5	1.376 (4)
C1—Sn1—C1^i	180.0	C6—C5—C4	120.3 (3)
C1—Sn1—Br1	90.53 (7)	C6—C5—H5	119.8
C1—Sn1—Br1^i	89.47 (7)	C4—C5—H5	119.8
C1—Sn1—Br2	89.64 (7)	C5—C6—C1	120.1 (3)
C1—Sn1—Br2^i	90.36 (7)	C5—C6—H6	120.0
C1^i—Sn1—Br1	89.47 (7)	C1—C6—H6	120.0
C1^i—Sn1—Br1^i	90.53 (7)	N1—C7—H7A	109.5
C1^i—Sn1—Br2	90.36 (7)	N1—C7—H7B	109.5
C1^i—Sn1—Br2^i	89.64 (7)	H7A—C7—H7B	109.5
Br1—Sn1—Br1^i	180.0	N1—C7—H7C	109.5
Br1—Sn1—Br2	88.981 (8)	H7A—C7—H7C	109.5
Br1—Sn1—Br2^i	91.019 (8)	H7B—C7—H7C	109.5
Br1^i—Sn1—Br2^i	88.981 (8)	N1—C8—H8A	109.5
Br1^i—Sn1—Br2	91.019 (8)	N1—C8—H8B	109.5
Br2—Sn1—Br2^i	180.0	H8A—C8—H8B	109.5
C9—N1—C7	120.7 (2)	N1—C8—H8C	109.5
C9—N1—C8	121.0 (2)	H8A—C8—H8C	109.5
C7—N1—C8	118.2 (2)	H8B—C8—H8C	109.5
C12—N2—C11	121.0 (3)	N1—C9—C10	122.1 (2)
C12—N2—H2N	118 (3)	N1—C9—C13	121.0 (3)
C11—N2—H2N	120 (3)	C10—C9—C13	116.9 (2)
C6—C1—C2	118.9 (3)	C11—C10—C9	120.0 (3)
C6—C1—Sn1	120.3 (2)	C11—C10—H10	120.0
C2—C1—Sn1	120.71 (19)	C9—C10—H10	120.0
C3—C2—C1	120.0 (3)	N2—C11—C10	120.8 (3)
C3—C2—H2	120.0	N2—C11—H11	119.6
C1—C2—H2	120.0	C10—C11—H11	119.6
C4—C3—C2	120.2 (3)	N2—C12—C13	121.5 (3)
C4—C3—H3	119.9	N2—C12—H12	119.3
C2—C3—H3	119.9	C13—C12—H12	119.3
C3—C4—C5	120.4 (3)	C12—C13—C9	119.7 (3)
C3—C4—H4	119.8	C12—C13—H13	120.1
C5—C4—H4	119.8	C9—C13—H13	120.1
Br1^i—Sn1—C1—C6	−130.5 (2)	C2—C1—C6—C5	1.7 (4)
Br1—Sn1—C1—C6	49.5 (2)	Sn1—C1—C6—C5	−175.7 (2)
Br2^i—Sn1—C1—C6	−41.5 (2)	C7—N1—C9—C10	−1.6 (4)
Br2—Sn1—C1—C6	138.5 (2)	C8—N1—C9—C10	−178.0 (2)
Br1^i—Sn1—C1—C2	52.2 (2)	C7—N1—C9—C13	178.9 (2)
Br1—Sn1—C1—C2	−127.8 (2)	C8—N1—C9—C13	2.6 (4)
Br2^i—Sn1—C1—C2	141.2 (2)	N1—C9—C10—C11	−176.8 (3)
Br2—Sn1—C1—C2	−38.8 (2)	C13—C9—C10—C11	2.6 (4)
C6—C1—C2—C3	−1.5 (4)	C12—N2—C11—C10	−1.4 (5)
Sn1—C1—C2—C3	175.9 (2)	C9—C10—C11—N2	−0.9 (4)
C1—C2—C3—C4	−0.2 (4)	C11—N2—C12—C13	1.7 (5)
C2—C3—C4—C5	1.7 (4)	N2—C12—C13—C9	0.2 (5)
C3—C4—C5—C6	−1.5 (4)	N1—C9—C13—C12	177.1 (3)
C4—C5—C6—C1	−0.2 (4)	C10—C9—C13—C12	−2.3 (4)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N···Br1	0.88 (1)	2.79 (3)	3.385 (3)	126 (3)
N2—H2N···Br2	0.88 (1)	2.81 (3)	3.485 (3)	135 (3)