2-Meth­oxy­carbonyl­pyridinium tetra­chlorido(pyridine-2-carboxyl­ato-κ2N,O)stannate(IV)

Najafi, E.; Amini, M.M.; Ng, S.W.

doi:10.1107/S1600536811001930

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 2| February 2011| Page m239

doi:10.1107/S1600536811001930

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2-Methoxycarbonylpyridinium tetrachlorido(pyridine-2-carboxylato-κ²N,O)stannate(IV)

Ezzatollah Najafi,^a Mostafa M. Amini ^a and Seik Weng Ng ^b ^*

^aDepartment of Chemistry, General Campus, Shahid Beheshti University, Tehran 1983963113, Iran, and ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 8 January 2011; accepted 12 January 2011; online 22 January 2011)

In the reaction of pyridine-2-carboxylic acid and stannic chloride in methanol, one equivalent of the carboxylic acid is protonated at the amino site and is also esterified, yielding the title salt, (C₇H₈NO₂)[SnCl₄(C₆H₄NO₂)]. The Sn^IV atom in the anion is N,O-chelated by a pyridine-2-carboxylate in a cis-SnNOCl₄ octahedral geometry. The cation is linked to the anion by an N—H⋯O hydrogen bond.

Related literature

For a related organotin structure, see: Nowell et al. (1983 ).

Experimental

Crystal data

(C₇H₈NO₂)[SnCl₄(C₆H₄NO₂)]
M_r = 520.74
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.8898 (3) Å
b = 10.3571 (3) Å
c = 20.0938 (7) Å
V = 1850.09 (10) Å³
Z = 4
Mo Kα radiation
μ = 1.98 mm⁻¹
T = 100 K
0.30 × 0.25 × 0.20 mm

Data collection

Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010 ) T_min = 0.588, T_max = 0.693
6191 measured reflections
3787 independent reflections
3679 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.049
S = 0.96
3787 reflections
222 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.68 e Å⁻³
Absolute structure: Flack (1983 ), 1428 Friedel pairs
Flack parameter: −0.03 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯O2	0.88 (3)	1.89 (1)	2.745 (3)	166 (3)

Data collection: CrysAlis PRO (Agilent Technologies, 2010); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811001930/si2326sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811001930/si2326Isup2.hkl

checkCIF report

Comment top

The direct synthesis of a potentially chelating amino-carboxylic acid with stannic tetrachloride has not been reported. Pyridine-2-carboxylic acid yields a number of derivatives with organotin compounds; these are either synthesized by condensing the amino-carboxylic acids with an organotin oxide/hydroxide or by reacting the amino-carboxylic acids with an organotin chloride in the presence of a proton abstractor. With the latter route, the product may be an organostannate in which the pyridine-2-carboxylate chelates to the chlorine-bonded tin atom (Nowell et al., 1983). In the reaction of pyridine-2-carboxylic acid and stannic chloride in methanol, one equivalent of the carboxylic acid is protonated at the amino site and is also esterified to yield the salt, [C₇H₈NO₂]⁺ [SnCl₄(C₆H₄NO₂)]^- (Scheme I, Fig. 1). The tin atom in the anion is N,O-chelated by a pyridine-2-carboxylate in an octahedral geometry. The cation is linked to the anion by an N–H···O hydrogen bond (Table 1).

Related literature top

For a related organotin structure, see: Nowell et al. (1983).

Experimental top

Stannic chloride pentahydrate 0.35 g, 1 mmol) and pyridine-2-carboxylic acid (0.13 g, 1 mmol) were loaded into a convection tube; the tube was filled with dry methanol and kept at 333 K. Colorless crystals were collected from the side arm after several days.

Computing details top

Data collection: CrysAlis PRO (Agilent Technologies, 2010); cell refinement: CrysAlis PRO (Agilent Technologies, 2010); data reduction: CrysAlis PRO (Agilent Technologies, 2010); 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, 2010).

Figures top

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of [C₇H₈NO₂]⁺ [SnCl₄(C₆H₄NO₂)]^- at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

2-Methoxycarbonylpyridinium tetrachlorido(pyridine-2-carboxylato-κ²N,O)stannate(IV) top

Crystal data top

(C₇H₈NO₂)[SnCl₄(C₆H₄NO₂)]	F(000) = 1016
M_r = 520.74	D_x = 1.870 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5063 reflections
a = 8.8898 (3) Å	θ = 2.5–29.3°
b = 10.3571 (3) Å	µ = 1.98 mm⁻¹
c = 20.0938 (7) Å	T = 100 K
V = 1850.09 (10) Å³	Prism, colorless
Z = 4	0.30 × 0.25 × 0.20 mm

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	3787 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	3679 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.021
Detector resolution: 10.4041 pixels mm^-1	θ_max = 27.5°, θ_min = 2.5°
ω scans	h = −11→7
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010)	k = −13→10
T_min = 0.588, T_max = 0.693	l = −25→15
6191 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.021	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.049	w = 1/[σ²(F_o²) + (0.0199P)² + 1.6372P] where P = (F_o² + 2F_c²)/3
S = 0.96	(Δ/σ)_max = 0.001
3787 reflections	Δρ_max = 0.36 e Å⁻³
222 parameters	Δρ_min = −0.68 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1428 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.03 (2)

Crystal data top

(C₇H₈NO₂)[SnCl₄(C₆H₄NO₂)]	V = 1850.09 (10) Å³
M_r = 520.74	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.8898 (3) Å	µ = 1.98 mm⁻¹
b = 10.3571 (3) Å	T = 100 K
c = 20.0938 (7) Å	0.30 × 0.25 × 0.20 mm

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	3787 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010)	3679 reflections with I > 2σ(I)
T_min = 0.588, T_max = 0.693	R_int = 0.021
6191 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.049	Δρ_max = 0.36 e Å⁻³
S = 0.96	Δρ_min = −0.68 e Å⁻³
3787 reflections	Absolute structure: Flack (1983), 1428 Friedel pairs
222 parameters	Absolute structure parameter: −0.03 (2)
1 restraint

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Sn1	0.389388 (18)	0.500107 (17)	0.098352 (8)	0.01202 (5)
Cl4	0.19677 (7)	0.49203 (9)	0.18312 (3)	0.01817 (13)
Cl3	0.59780 (8)	0.48209 (7)	0.02047 (3)	0.01800 (14)
Cl2	0.39844 (9)	0.72817 (6)	0.09456 (4)	0.02160 (15)
Cl1	0.21001 (8)	0.46486 (7)	0.01310 (4)	0.02040 (16)
O1	0.54531 (19)	0.5006 (2)	0.17598 (8)	0.0163 (4)
O2	0.6707 (2)	0.3817 (2)	0.24920 (10)	0.0217 (5)
O3	0.9194 (2)	0.2695 (2)	0.17094 (10)	0.0202 (4)
O4	1.1105 (3)	0.1264 (2)	0.16977 (11)	0.0271 (5)
N1	0.4309 (3)	0.2927 (2)	0.11697 (11)	0.0127 (5)
N2	0.9440 (3)	0.3078 (2)	0.30014 (13)	0.0148 (5)
H2	0.866 (2)	0.338 (3)	0.2787 (14)	0.012 (8)*
C1	0.5869 (3)	0.3918 (3)	0.20127 (13)	0.0156 (6)
C2	0.5262 (3)	0.2717 (3)	0.16754 (13)	0.0148 (6)
C3	0.5707 (4)	0.1491 (3)	0.18569 (14)	0.0195 (6)
H3	0.6361	0.1358	0.2225	0.023*
C4	0.5172 (3)	0.0454 (3)	0.14858 (15)	0.0208 (6)
H4	0.5467	−0.0402	0.1594	0.025*
C5	0.4211 (3)	0.0678 (3)	0.09613 (15)	0.0196 (6)
H5	0.3850	−0.0020	0.0700	0.024*
C6	0.3776 (3)	0.1931 (3)	0.08186 (14)	0.0158 (6)
H6	0.3088	0.2085	0.0466	0.019*
C7	0.9024 (4)	0.2550 (3)	0.09935 (16)	0.0295 (7)
H7A	0.8182	0.3084	0.0840	0.044*
H7B	0.8824	0.1643	0.0887	0.044*
H7C	0.9950	0.2827	0.0771	0.044*
C8	1.0302 (4)	0.2023 (3)	0.19757 (16)	0.0182 (7)
C9	1.0474 (3)	0.2317 (3)	0.27057 (14)	0.0154 (6)
C10	1.1650 (4)	0.1834 (3)	0.30627 (15)	0.0209 (6)
H10	1.2384	0.1302	0.2856	0.025*
C11	1.1758 (4)	0.2136 (3)	0.37360 (17)	0.0266 (7)
H11	1.2564	0.1803	0.3995	0.032*
C12	1.0684 (4)	0.2923 (3)	0.40256 (17)	0.0239 (7)
H12	1.0752	0.3138	0.4484	0.029*
C13	0.9520 (4)	0.3391 (3)	0.36472 (15)	0.0177 (6)
H13	0.8777	0.3932	0.3842	0.021*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Sn1	0.01237 (8)	0.01123 (8)	0.01245 (8)	0.00035 (11)	−0.00144 (7)	−0.00058 (8)
Cl4	0.0168 (3)	0.0182 (3)	0.0195 (3)	−0.0011 (4)	0.0035 (2)	−0.0029 (3)
Cl3	0.0173 (3)	0.0198 (3)	0.0170 (3)	0.0010 (3)	0.0027 (3)	0.0005 (3)
Cl2	0.0263 (4)	0.0115 (3)	0.0270 (4)	0.0001 (3)	0.0020 (4)	−0.0006 (3)
Cl1	0.0186 (3)	0.0253 (4)	0.0173 (3)	0.0008 (3)	−0.0061 (3)	−0.0007 (3)
O1	0.0159 (8)	0.0182 (8)	0.0148 (8)	−0.0015 (12)	−0.0046 (7)	0.0011 (10)
O2	0.0170 (10)	0.0324 (11)	0.0156 (10)	0.0063 (10)	−0.0037 (9)	−0.0041 (9)
O3	0.0186 (11)	0.0297 (11)	0.0123 (9)	0.0005 (10)	−0.0002 (9)	−0.0031 (8)
O4	0.0294 (12)	0.0277 (10)	0.0242 (11)	0.0063 (12)	0.0070 (11)	−0.0067 (9)
N1	0.0132 (12)	0.0110 (10)	0.0139 (12)	0.0013 (10)	0.0015 (10)	0.0005 (8)
N2	0.0097 (12)	0.0163 (12)	0.0184 (13)	0.0012 (10)	−0.0026 (11)	0.0034 (10)
C1	0.0101 (13)	0.0242 (14)	0.0123 (12)	0.0042 (12)	0.0038 (11)	−0.0027 (11)
C2	0.0138 (13)	0.0190 (13)	0.0115 (13)	0.0018 (12)	0.0022 (11)	0.0021 (10)
C3	0.0210 (15)	0.0220 (14)	0.0155 (14)	0.0036 (13)	0.0025 (12)	0.0055 (11)
C4	0.0220 (15)	0.0150 (12)	0.0253 (16)	0.0023 (12)	0.0100 (13)	0.0063 (11)
C5	0.0212 (14)	0.0132 (12)	0.0245 (14)	−0.0020 (12)	0.0076 (14)	−0.0009 (11)
C6	0.0153 (13)	0.0151 (12)	0.0170 (14)	−0.0025 (12)	0.0034 (12)	−0.0015 (10)
C7	0.0268 (17)	0.0482 (19)	0.0134 (14)	0.0025 (18)	−0.0033 (17)	−0.0023 (15)
C8	0.0177 (15)	0.0183 (14)	0.0186 (16)	−0.0025 (13)	0.0012 (14)	−0.0014 (12)
C9	0.0145 (13)	0.0136 (12)	0.0181 (14)	−0.0013 (11)	0.0008 (12)	0.0009 (10)
C10	0.0172 (14)	0.0204 (14)	0.0253 (16)	0.0060 (12)	−0.0009 (14)	−0.0009 (12)
C11	0.0224 (16)	0.0333 (17)	0.0241 (16)	0.0063 (15)	−0.0067 (15)	0.0012 (14)
C12	0.0242 (16)	0.0292 (15)	0.0183 (14)	0.0027 (14)	−0.0047 (15)	−0.0018 (14)
C13	0.0184 (14)	0.0180 (13)	0.0165 (14)	0.0019 (12)	−0.0012 (12)	−0.0015 (11)

Geometric parameters (Å, º) top

Sn1—O1	2.0868 (16)	C3—H3	0.9500
Sn1—N1	2.211 (2)	C4—C5	1.376 (4)
Sn1—Cl2	2.3647 (6)	C4—H4	0.9500
Sn1—Cl1	2.3687 (7)	C5—C6	1.384 (4)
Sn1—Cl4	2.4167 (6)	C5—H5	0.9500
Sn1—Cl3	2.4325 (7)	C6—H6	0.9500
O1—C1	1.291 (3)	C7—H7A	0.9800
O2—C1	1.222 (3)	C7—H7B	0.9800
O3—C8	1.320 (4)	C7—H7C	0.9800
O3—C7	1.454 (4)	C8—C9	1.506 (4)
O4—C8	1.199 (4)	C9—C10	1.363 (4)
N1—C2	1.341 (4)	C10—C11	1.392 (4)
N1—C6	1.337 (3)	C10—H10	0.9500
N2—C13	1.339 (4)	C11—C12	1.384 (5)
N2—C9	1.348 (4)	C11—H11	0.9500
N2—H2	0.88 (2)	C12—C13	1.373 (4)
C1—C2	1.516 (4)	C12—H12	0.9500
C2—C3	1.379 (4)	C13—H13	0.9500
C3—C4	1.391 (4)

O1—Sn1—N1	76.42 (9)	C5—C4—H4	120.2
O1—Sn1—Cl2	89.93 (7)	C3—C4—H4	120.2
N1—Sn1—Cl2	165.94 (7)	C4—C5—C6	119.3 (3)
O1—Sn1—Cl1	171.19 (7)	C4—C5—H5	120.3
N1—Sn1—Cl1	94.88 (6)	C6—C5—H5	120.3
Cl2—Sn1—Cl1	98.83 (3)	N1—C6—C5	121.0 (3)
O1—Sn1—Cl4	86.78 (5)	N1—C6—H6	119.5
N1—Sn1—Cl4	88.02 (6)	C5—C6—H6	119.5
Cl2—Sn1—Cl4	94.67 (3)	O3—C7—H7A	109.5
Cl1—Sn1—Cl4	91.57 (2)	O3—C7—H7B	109.5
O1—Sn1—Cl3	88.58 (5)	H7A—C7—H7B	109.5
N1—Sn1—Cl3	84.67 (6)	O3—C7—H7C	109.5
Cl2—Sn1—Cl3	91.72 (3)	H7A—C7—H7C	109.5
Cl1—Sn1—Cl3	92.04 (2)	H7B—C7—H7C	109.5
Cl4—Sn1—Cl3	172.10 (3)	O4—C8—O3	126.9 (3)
C1—O1—Sn1	118.83 (19)	O4—C8—C9	121.7 (3)
C8—O3—C7	115.1 (2)	O3—C8—C9	111.3 (3)
C2—N1—C6	119.9 (2)	N2—C9—C10	120.3 (3)
C2—N1—Sn1	113.08 (18)	N2—C9—C8	118.6 (3)
C6—N1—Sn1	126.95 (19)	C10—C9—C8	121.1 (3)
C13—N2—C9	122.2 (3)	C9—C10—C11	118.8 (3)
C13—N2—H2	116 (2)	C9—C10—H10	120.6
C9—N2—H2	122 (2)	C11—C10—H10	120.6
O2—C1—O1	124.0 (3)	C10—C11—C12	119.6 (3)
O2—C1—C2	119.9 (2)	C10—C11—H11	120.2
O1—C1—C2	116.0 (2)	C12—C11—H11	120.2
N1—C2—C3	122.1 (3)	C13—C12—C11	119.7 (3)
N1—C2—C1	115.5 (2)	C13—C12—H12	120.1
C3—C2—C1	122.4 (3)	C11—C12—H12	120.1
C2—C3—C4	118.1 (3)	N2—C13—C12	119.4 (3)
C2—C3—H3	121.0	N2—C13—H13	120.3
C4—C3—H3	121.0	C12—C13—H13	120.3
C5—C4—C3	119.5 (3)

N1—Sn1—O1—C1	−3.82 (19)	O1—C1—C2—C3	174.6 (3)
Cl2—Sn1—O1—C1	179.60 (18)	N1—C2—C3—C4	1.8 (4)
Cl4—Sn1—O1—C1	84.92 (18)	C1—C2—C3—C4	−175.4 (3)
Cl3—Sn1—O1—C1	−88.68 (18)	C2—C3—C4—C5	−0.9 (4)
O1—Sn1—N1—C2	2.07 (18)	C3—C4—C5—C6	−1.0 (4)
Cl2—Sn1—N1—C2	16.3 (4)	C2—N1—C6—C5	−1.1 (4)
Cl1—Sn1—N1—C2	−176.51 (18)	Sn1—N1—C6—C5	175.4 (2)
Cl4—Sn1—N1—C2	−85.10 (19)	C4—C5—C6—N1	2.0 (4)
Cl3—Sn1—N1—C2	91.89 (19)	C7—O3—C8—O4	−4.7 (5)
O1—Sn1—N1—C6	−174.6 (3)	C7—O3—C8—C9	175.2 (3)
Cl2—Sn1—N1—C6	−160.4 (2)	C13—N2—C9—C10	0.1 (4)
Cl1—Sn1—N1—C6	6.8 (2)	C13—N2—C9—C8	−179.6 (2)
Cl4—Sn1—N1—C6	98.3 (2)	O4—C8—C9—N2	−173.4 (3)
Cl3—Sn1—N1—C6	−84.8 (2)	O3—C8—C9—N2	6.7 (4)
Sn1—O1—C1—O2	−175.6 (2)	O4—C8—C9—C10	7.0 (5)
Sn1—O1—C1—C2	4.8 (3)	O3—C8—C9—C10	−173.0 (3)
C6—N1—C2—C3	−0.9 (4)	N2—C9—C10—C11	0.4 (4)
Sn1—N1—C2—C3	−177.8 (2)	C8—C9—C10—C11	180.0 (3)
C6—N1—C2—C1	176.5 (2)	C9—C10—C11—C12	−0.6 (5)
Sn1—N1—C2—C1	−0.4 (3)	C10—C11—C12—C13	0.4 (5)
O2—C1—C2—N1	177.7 (2)	C9—N2—C13—C12	−0.3 (4)
O1—C1—C2—N1	−2.7 (4)	C11—C12—C13—N2	0.0 (5)
O2—C1—C2—C3	−5.0 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O2	0.88 (3)	1.89 (1)	2.745 (3)	166 (3)

Experimental details

Crystal data
Chemical formula	(C₇H₈NO₂)[SnCl₄(C₆H₄NO₂)]
M_r	520.74
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	8.8898 (3), 10.3571 (3), 20.0938 (7)
V (Å³)	1850.09 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.98
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction	Multi-scan (CrysAlis PRO; Agilent Technologies, 2010)
T_min, T_max	0.588, 0.693
No. of measured, independent and observed [I > 2σ(I)] reflections	6191, 3787, 3679
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.049, 0.96
No. of reflections	3787
No. of parameters	222
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.68
Absolute structure	Flack (1983), 1428 Friedel pairs
Absolute structure parameter	−0.03 (2)

Computer programs: CrysAlis PRO (Agilent Technologies, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O2	0.88 (3)	1.887 (13)	2.745 (3)	166 (3)

Acknowledgements

We thank Shahid Beheshti University and the University of Malaya for supporting this study.

References

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