2-(Methoxy­carbon­yl)anilinium dihydrogen phosphate

Shafiq, M.; Khan, I.U.; Arshad, M.N.; Khan, M.H.; Simpson, J.

doi:10.1107/S1600536809025252

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o1786

doi:10.1107/S1600536809025252

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2-(Methoxycarbonyl)anilinium dihydrogen phosphate

Muhammad Shafiq,^a Islam Ullah Khan,^a Muhammad Nadeem Arshad,^a ^* Muneeb Hayat Khan ^a and Jim Simpson ^b

^aMaterials Chemistry laboratory, Department of Chemistry, GC University, Lahore, Pakistan, and ^bDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
^*Correspondence e-mail: mnachemist@hotmail.com

(Received 29 June 2009; accepted 30 June 2009; online 4 July 2009)

The title compound, C₈H₁₀NO₂⁺·H₂PO₄⁻, is a derivative of the naturally occurring compound methylanthranilate. The asymmetric unit comprises the 2-(methoxycarbonyl)anilinium cation and the dihydrogen phosphate anion. In the cation, the dihedral angle between the benzene ring plane and that through the methyl ester substituent is 22.94 (9)°. In the crystal, adjacent cations and anions form dimers through N—H⋯O and O—H⋯O hydrogen bonds, respectively. Additional N—H⋯O and C—H⋯O contacts result in a network of cation and anion dimers stacked down the b axis.

Related literature

For thiazine-related heterocycles see: Shafiq et al. (2009a ). For related structures, see: Gel'mbol'dt et al. (2006 ); Ma et al. (2005 ); Shafiq et al. (2008 , 2009b ).

Experimental

Crystal data

C₈H₁₀NO₂⁺·H₂PO₄⁻
M_r = 249.16
Monoclinic, C 2/c
a = 20.939 (3) Å
b = 4.7880 (5) Å
c = 22.283 (4) Å
β = 114.970 (5)°
V = 2025.2 (5) Å³
Z = 8
Mo Kα radiation
μ = 0.29 mm⁻¹
T = 296 K
0.39 × 0.21 × 0.17 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.928, T_max = 0.958
10812 measured reflections
2413 independent reflections
2078 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.102
S = 1.07
2413 reflections
153 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.48 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯O5	0.93	2.68	3.387 (2)	133
C4—H4⋯O6	0.93	2.71	3.590 (2)	158
C3—H3⋯O2ⁱ	0.93	2.72	3.609 (2)	162
N1—H1A⋯O3ⁱⁱ	0.89	1.93	2.8218 (18)	178
N1—H1A⋯O5ⁱⁱ	0.89	2.68	3.190 (2)	118
N1—H1C⋯O3ⁱⁱⁱ	0.89	2.01	2.9005 (18)	175
N1—H1B⋯O3^iv	0.89	2.09	2.9400 (17)	160
O5—H5O⋯O6^v	0.78 (2)	1.83 (2)	2.6021 (17)	170 (2)
O4—H4O⋯O6^vi	0.72 (2)	1.88 (2)	2.6015 (17)	179 (2)
Symmetry codes: (i) $[-x, y, -z+{\script{3\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (iii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (iv) $[x, -y+1, z+{\script{1\over 2}}]$ ; (v) x, y+1, z; (vi) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004 ), PLATON (Spek, 2009 ) and publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809025252/bt2987sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809025252/bt2987Isup2.hkl

checkCIF report

Comment top

Methylanthranilite is a naturally occurring compound which has been used in food flavoring, as a fragrance additive and a bird repellent. Our group has been involved in the synthesis of heterocyclic molecules related to benzothiazine (Shafiq et al., 2009a) in which the title compound has been used as a starting material (Shafiq et al., 2008; Shafiq et al., 2009b). Herein we report the structure of title compound which was obtained during the synthesis of methylanthranilate Schiff base derivatives.

The asymmetric unit comprises the 2-(methoxycarbonyl)anilinium cation and the dihydrogen phosphate anion linked by bifurcated C4–H4···O5 and C4—H4···O6 interactions, Fig. 1. In the cation the dihedral angle between the C1···C6 benzene ring plane and that through the C2,C7(O1),O2,C8 atoms of the methyl ester substituent is 22.94 (9) °. Bond distances within the molecule are normal and similar to those observed in comparable structures (Gel'mbol'dt et al., 2006; Ma et al., 2005). In the crystal, adjacent cations and anions form dimers through N1—H1A···O1 and O4—H4O···O6 hydrogen bonds respectively, Fig. 2. Additional N—H···O and C—H···O contacts result in a network of cation and anion dimers stacked down the b axis, Fig. 3.

Related literature top

For thiazine-related heterocycles see: Shafiq et al. (2009a). For related structures, see: Gel'mbol'dt et al. (2006); Ma et al. (2005); Shafiq et al. (2008, 2009b)

Experimental top

The title compound was obtained during the synthesis of Schiff base of methyl anthranilate. Methyl anthranilite (0.5 g, 0.0 mol) was dissolved in methanol (5 ml). A few drops of polyphosphoric acid were added to the above solution to precipitate the product which was recrystalized from methanol.

Computing details top

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: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2009).

Figures top

	Fig. 1. The asymmetric unit of (I) with displacement ellipsoids for the non-hydrogen atoms drawn at the 50% probability level. Hydrogen bonds are drawn as dashed lines.
	Fig. 2. Dimers formed by the cations and anions in the structure of (I) with hydrogen bonds drawn as dashed lines.
	Fig. 3. Crystal packing of (I) viewed down the b axis

2-(Methoxycarbonyl)anilinium dihydrogen phosphate top

Crystal data top

C₈H₁₀NO₂⁺·H₂PO₄⁻	F(000) = 1040
M_r = 249.16	D_x = 1.634 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5124 reflections
a = 20.939 (3) Å	θ = 2.2–27.9°
b = 4.7880 (5) Å	µ = 0.29 mm⁻¹
c = 22.283 (4) Å	T = 296 K
β = 114.970 (5)°	Needle, colourless
V = 2025.2 (5) Å³	0.39 × 0.21 × 0.17 mm
Z = 8

Data collection top

Bruker Kappa APEXII CCD diffractometer	2413 independent reflections
Radiation source: fine-focus sealed tube	2078 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 27.9°, θ_min = 3.5°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −27→27
T_min = 0.928, T_max = 0.958	k = −4→6
10812 measured reflections	l = −29→27

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.102	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0575P)² + 1.6713P] where P = (F_o² + 2F_c²)/3
2413 reflections	(Δ/σ)_max = 0.001
153 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.48 e Å⁻³

Crystal data top

C₈H₁₀NO₂⁺·H₂PO₄⁻	V = 2025.2 (5) Å³
M_r = 249.16	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 20.939 (3) Å	µ = 0.29 mm⁻¹
b = 4.7880 (5) Å	T = 296 K
c = 22.283 (4) Å	0.39 × 0.21 × 0.17 mm
β = 114.970 (5)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2413 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2078 reflections with I > 2σ(I)
T_min = 0.928, T_max = 0.958	R_int = 0.035
10812 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.102	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.29 e Å⁻³
2413 reflections	Δρ_min = −0.48 e Å⁻³
153 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.24287 (7)	0.4968 (3)	0.93401 (6)	0.0200 (3)
H1A	0.2695	0.3443	0.9473	0.030*
H1B	0.2127	0.5014	0.9526	0.030*
H1C	0.2702	0.6478	0.9460	0.030*
C1	0.20379 (8)	0.4920 (3)	0.86203 (7)	0.0202 (3)
C2	0.14685 (8)	0.3118 (3)	0.83134 (7)	0.0227 (3)
C3	0.11163 (9)	0.3157 (4)	0.76239 (8)	0.0300 (4)
H3	0.0730	0.1996	0.7412	0.036*
C4	0.13337 (10)	0.4893 (4)	0.72527 (9)	0.0326 (4)
H4	0.1102	0.4864	0.6793	0.039*
C5	0.18948 (10)	0.6671 (4)	0.75648 (9)	0.0322 (4)
H5	0.2038	0.7857	0.7315	0.039*
C6	0.22462 (9)	0.6700 (4)	0.82496 (8)	0.0273 (4)
H6	0.2622	0.7916	0.8459	0.033*
C7	0.12565 (8)	0.1075 (3)	0.86989 (8)	0.0225 (3)
C8	0.03453 (11)	−0.1887 (5)	0.86660 (11)	0.0433 (5)
H8A	0.0609	−0.1795	0.9138	0.065*
H8B	0.0402	−0.3700	0.8511	0.065*
H8C	−0.0144	−0.1566	0.8555	0.065*
O1	0.16391 (6)	0.0261 (3)	0.92428 (6)	0.0273 (3)
O2	0.05989 (7)	0.0218 (3)	0.83567 (7)	0.0380 (3)
P1	0.10739 (2)	0.56312 (8)	0.531833 (19)	0.01826 (13)
O3	0.17510 (6)	0.5066 (2)	0.52576 (6)	0.0248 (3)
O4	0.05239 (6)	0.6781 (3)	0.46425 (6)	0.0262 (3)
H4O	0.0163 (12)	0.681 (5)	0.4598 (10)	0.031*
O5	0.12078 (7)	0.8011 (3)	0.58427 (6)	0.0323 (3)
H5O	0.1063 (13)	0.948 (5)	0.5709 (11)	0.039*
O6	0.07879 (6)	0.3146 (2)	0.55400 (6)	0.0255 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0199 (6)	0.0202 (6)	0.0191 (6)	−0.0008 (5)	0.0075 (5)	−0.0015 (5)
C1	0.0202 (7)	0.0201 (7)	0.0196 (7)	0.0040 (6)	0.0076 (6)	−0.0003 (6)
C2	0.0230 (8)	0.0219 (7)	0.0215 (7)	0.0022 (6)	0.0079 (6)	0.0005 (6)
C3	0.0277 (9)	0.0334 (9)	0.0222 (8)	−0.0011 (7)	0.0038 (6)	−0.0010 (7)
C4	0.0353 (10)	0.0407 (10)	0.0194 (8)	0.0074 (8)	0.0091 (7)	0.0046 (7)
C5	0.0365 (10)	0.0354 (9)	0.0294 (9)	0.0048 (8)	0.0185 (7)	0.0085 (8)
C6	0.0277 (8)	0.0260 (8)	0.0295 (8)	−0.0016 (7)	0.0134 (7)	0.0009 (7)
C7	0.0219 (7)	0.0202 (7)	0.0235 (8)	−0.0008 (6)	0.0077 (6)	−0.0031 (6)
C8	0.0388 (11)	0.0397 (11)	0.0495 (12)	−0.0184 (9)	0.0167 (9)	0.0013 (9)
O1	0.0257 (6)	0.0293 (6)	0.0241 (6)	0.0007 (5)	0.0078 (5)	0.0036 (5)
O2	0.0268 (7)	0.0436 (8)	0.0329 (7)	−0.0137 (6)	0.0022 (5)	0.0073 (6)
P1	0.0173 (2)	0.0154 (2)	0.0226 (2)	0.00185 (14)	0.00890 (16)	0.00206 (14)
O3	0.0181 (6)	0.0250 (6)	0.0324 (6)	0.0032 (4)	0.0118 (5)	0.0025 (5)
O4	0.0179 (5)	0.0338 (7)	0.0261 (6)	0.0029 (5)	0.0086 (5)	0.0069 (5)
O5	0.0466 (8)	0.0189 (6)	0.0277 (6)	0.0072 (5)	0.0122 (6)	0.0001 (5)
O6	0.0234 (6)	0.0186 (5)	0.0363 (6)	0.0010 (4)	0.0142 (5)	0.0060 (5)

Geometric parameters (Å, º) top

N1—C1	1.4609 (19)	C6—H6	0.9300
N1—H1A	0.8900	C7—O1	1.2010 (19)
N1—H1B	0.8900	C7—O2	1.326 (2)
N1—H1C	0.8900	C8—O2	1.443 (2)
C1—C6	1.379 (2)	C8—H8A	0.9600
C1—C2	1.395 (2)	C8—H8B	0.9600
C2—C3	1.396 (2)	C8—H8C	0.9600
C2—C7	1.488 (2)	P1—O3	1.5045 (12)
C3—C4	1.379 (3)	P1—O6	1.5062 (12)
C3—H3	0.9300	P1—O4	1.5597 (12)
C4—C5	1.378 (3)	P1—O5	1.5702 (13)
C4—H4	0.9300	O4—H4O	0.72 (2)
C5—C6	1.386 (2)	O5—H5O	0.78 (2)
C5—H5	0.9300

C1—N1—H1A	109.5	C1—C6—C5	119.85 (16)
C1—N1—H1B	109.5	C1—C6—H6	120.1
H1A—N1—H1B	109.5	C5—C6—H6	120.1
C1—N1—H1C	109.5	O1—C7—O2	124.62 (16)
H1A—N1—H1C	109.5	O1—C7—C2	124.15 (15)
H1B—N1—H1C	109.5	O2—C7—C2	111.21 (14)
C6—C1—C2	120.64 (15)	O2—C8—H8A	109.5
C6—C1—N1	118.39 (14)	O2—C8—H8B	109.5
C2—C1—N1	120.97 (14)	H8A—C8—H8B	109.5
C1—C2—C3	118.45 (15)	O2—C8—H8C	109.5
C1—C2—C7	121.69 (14)	H8A—C8—H8C	109.5
C3—C2—C7	119.77 (15)	H8B—C8—H8C	109.5
C4—C3—C2	120.91 (17)	C7—O2—C8	116.33 (15)
C4—C3—H3	119.5	O3—P1—O6	114.06 (7)
C2—C3—H3	119.5	O3—P1—O4	108.44 (7)
C5—C4—C3	119.79 (16)	O6—P1—O4	111.21 (7)
C5—C4—H4	120.1	O3—P1—O5	108.56 (7)
C3—C4—H4	120.1	O6—P1—O5	107.47 (7)
C4—C5—C6	120.33 (17)	O4—P1—O5	106.83 (7)
C4—C5—H5	119.8	P1—O4—H4O	116.4 (17)
C6—C5—H5	119.8	P1—O5—H5O	117.1 (18)

C6—C1—C2—C3	0.1 (2)	N1—C1—C6—C5	178.83 (15)
N1—C1—C2—C3	−179.80 (15)	C4—C5—C6—C1	0.7 (3)
C6—C1—C2—C7	176.75 (15)	C1—C2—C7—O1	−21.1 (2)
N1—C1—C2—C7	−3.1 (2)	C3—C2—C7—O1	155.53 (17)
C1—C2—C3—C4	1.3 (3)	C1—C2—C7—O2	160.61 (16)
C7—C2—C3—C4	−175.43 (16)	C3—C2—C7—O2	−22.8 (2)
C2—C3—C4—C5	−1.7 (3)	O1—C7—O2—C8	−1.5 (3)
C3—C4—C5—C6	0.7 (3)	C2—C7—O2—C8	176.80 (16)
C2—C1—C6—C5	−1.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O5	0.93	2.68	3.387 (2)	133
C4—H4···O6	0.93	2.71	3.590 (2)	158
C3—H3···O2ⁱ	0.93	2.72	3.609 (2)	162
N1—H1A···O3ⁱⁱ	0.89	1.93	2.8218 (18)	178
N1—H1A···O5ⁱⁱ	0.89	2.68	3.190 (2)	118
N1—H1C···O3ⁱⁱⁱ	0.89	2.01	2.9005 (18)	175
N1—H1B···O3^iv	0.89	2.09	2.9400 (17)	160
O5—H5O···O6^v	0.78 (2)	1.83 (2)	2.6021 (17)	170 (2)
O4—H4O···O6^vi	0.72 (2)	1.88 (2)	2.6015 (17)	179 (2)

Symmetry codes: (i) −x, y, −z+3/2; (ii) −x+1/2, y−1/2, −z+3/2; (iii) −x+1/2, y+1/2, −z+3/2; (iv) x, −y+1, z+1/2; (v) x, y+1, z; (vi) −x, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₈H₁₀NO₂⁺·H₂PO₄⁻
M_r	249.16
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	296
a, b, c (Å)	20.939 (3), 4.7880 (5), 22.283 (4)
β (°)	114.970 (5)
V (Å³)	2025.2 (5)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.29
Crystal size (mm)	0.39 × 0.21 × 0.17

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.928, 0.958
No. of measured, independent and observed [I > 2σ(I)] reflections	10812, 2413, 2078
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.658

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.102, 1.07
No. of reflections	2413
No. of parameters	153
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.48

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O5	0.93	2.68	3.387 (2)	133.1
C4—H4···O6	0.93	2.71	3.590 (2)	157.8
C3—H3···O2ⁱ	0.93	2.72	3.609 (2)	161.5
N1—H1A···O3ⁱⁱ	0.89	1.93	2.8218 (18)	178.3
N1—H1A···O5ⁱⁱ	0.89	2.68	3.190 (2)	117.6
N1—H1C···O3ⁱⁱⁱ	0.89	2.01	2.9005 (18)	174.8
N1—H1B···O3^iv	0.89	2.09	2.9400 (17)	159.8
O5—H5O···O6^v	0.78 (2)	1.83 (2)	2.6021 (17)	170 (2)
O4—H4O···O6^vi	0.72 (2)	1.88 (2)	2.6015 (17)	179 (2)

Symmetry codes: (i) −x, y, −z+3/2; (ii) −x+1/2, y−1/2, −z+3/2; (iii) −x+1/2, y+1/2, −z+3/2; (iv) x, −y+1, z+1/2; (v) x, y+1, z; (vi) −x, −y+1, −z+1.

Acknowledgements

MS & MNA acknowledge the Higher Education Commission of Pakistan for providing PhD Scholarships under the Indigenous 5000 PhD fellowship program.

References

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