4-Methyl­anilinium 3-carb­oxy-2-hy­droxy­propano­ate

The title mol­ecular salt, C₇H₁₀N⁺·C₄H₅O₅⁻, contains a 4-methyl­anilinium cation and a 3-carb­oxy-2-hy­droxy­propano­ate (hydrogen 2-hy­droxy­succinate) anion in the asymmetric unit. The cation is protonated at the amine N atom and the anion is deprotonated at one of the hy­droxy O atoms of the carb­oxy­lic acid groups. An O—H...O hydrogen bond in the anion generates an S(5) graph-set motif. An N—H...O hydrogen bond links the anion and cation in the asymmetric unit. In the crystal, N—H...O and O—H...O hydrogen bonds link adjacent anions and cations, forming a two-dimensional network parallel to the ac plane and enclosing R₂³(12), R₂³(14) and R₃²(10) ring motifs.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.048
• wR factor = 0.136
• Data-to-parameter ratio = 19.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....        2.4 Note
PLAT334_ALERT_2_C Small Average Benzene  C-C Dist. C1     -C6            1.37 Ang.

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          8 Note
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ     Please Check
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          5 Report
PLAT793_ALERT_4_G The Model has Chirality at C9      (Centro SPGR)          R Verify
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          5 Note
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         35 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density           5 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   7 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 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
   3 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL2016 (Sheldrick, 2015) and PLATON (Spek, 2009).

4-Methylanilinium 3-carboxy-2-hydroxypropanoate

Crystal data

C7H10N^+·C4H5O5^−	F(000) = 512
Mr = 241.24	Dx = 1.340 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.4849 (8) Å	Cell parameters from 5534 reflections
b = 16.1306 (16) Å	θ = 2.4–29.6°
c = 10.4904 (10) Å	µ = 0.11 mm^−1
β = 109.234 (3)°	T = 295 K
V = 1195.9 (2) Å^3	Block, colourless
Z = 4	0.26 × 0.22 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	2078 reflections with I > 2σ(I)
ω and φ scan	Rint = 0.047
Absorption correction: multi-scan (SADABS; Bruker, 2004)	θmax = 29.9°, θmin = 2.4°
Tmin = 0.686, Tmax = 0.746	h = −10→10
19297 measured reflections	k = −22→22
3403 independent reflections	l = −14→14

Refinement

Refinement on F^2	5 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.048	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.136	w = 1/[σ^2(Fo^2) + (0.055P)^2 + 0.3504P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max < 0.001
3403 reflections	Δρmax = 0.37 e Å^−3
173 parameters	Δρmin = −0.20 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

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

	x	y	z	Uiso*/Ueq
C1	0.2423 (3)	0.50050 (12)	0.9996 (2)	0.0447 (5)
C2	0.2804 (3)	0.58051 (13)	1.04649 (19)	0.0498 (5)
H2	0.322596	0.590187	1.139054	0.060*
C3	0.2574 (3)	0.64649 (12)	0.95917 (17)	0.0436 (4)
H3	0.284307	0.700093	0.992660	0.052*
C4	0.1946 (2)	0.63270 (10)	0.82288 (16)	0.0297 (4)
C5	0.1539 (3)	0.55398 (12)	0.77248 (19)	0.0463 (5)
H5	0.110417	0.544643	0.679829	0.056*
C6	0.1787 (3)	0.48874 (13)	0.8621 (2)	0.0544 (5)
H6	0.151451	0.435215	0.828325	0.065*
C7	0.2706 (3)	0.42870 (15)	1.0955 (3)	0.0683 (7)
H7A	0.267825	0.448194	1.181262	0.102*
H7B	0.390753	0.403169	1.106808	0.102*
H7C	0.171438	0.388864	1.059646	0.102*
C8	0.8664 (2)	0.81546 (11)	0.87375 (15)	0.0300 (4)
C9	0.6854 (2)	0.80756 (11)	0.91036 (16)	0.0329 (4)
H9	0.711761	0.770807	0.988796	0.039*
C10	0.6193 (2)	0.88973 (11)	0.94679 (19)	0.0372 (4)
H10A	0.591569	0.927381	0.870639	0.045*
H10B	0.717729	0.914278	1.022132	0.045*
C11	0.4433 (2)	0.87581 (10)	0.98457 (16)	0.0307 (4)
N1	0.16966 (19)	0.70315 (10)	0.73151 (15)	0.0324 (3)
O1	0.86759 (15)	0.78284 (8)	0.76746 (12)	0.0398 (3)
O2	1.00180 (15)	0.85307 (9)	0.95801 (11)	0.0443 (3)
O3	0.28940 (16)	0.90265 (10)	0.89417 (13)	0.0509 (4)
O4	0.44432 (17)	0.84089 (9)	1.08584 (13)	0.0495 (4)
O5	0.53901 (15)	0.77145 (8)	0.80248 (12)	0.0405 (3)
H1A	0.2777 (18)	0.7287 (12)	0.753 (2)	0.052 (6)*
H1B	0.080 (2)	0.7348 (11)	0.739 (2)	0.050 (6)*
H1C	0.131 (3)	0.6877 (13)	0.6475 (11)	0.058 (6)*
H3A	0.197 (3)	0.8863 (16)	0.915 (3)	0.087*
H5A	0.589 (3)	0.7479 (16)	0.754 (2)	0.087*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0391 (10)	0.0430 (11)	0.0527 (12)	0.0069 (8)	0.0160 (8)	0.0088 (9)
C2	0.0566 (12)	0.0563 (13)	0.0313 (9)	−0.0025 (10)	0.0073 (8)	0.0025 (9)
C3	0.0539 (11)	0.0403 (11)	0.0338 (9)	−0.0078 (8)	0.0109 (8)	−0.0075 (8)
C4	0.0236 (7)	0.0348 (9)	0.0322 (8)	0.0010 (6)	0.0111 (6)	−0.0015 (7)
C5	0.0604 (12)	0.0433 (11)	0.0345 (9)	−0.0009 (9)	0.0146 (8)	−0.0094 (8)
C6	0.0715 (14)	0.0345 (11)	0.0581 (13)	−0.0012 (10)	0.0226 (11)	−0.0069 (9)
C7	0.0657 (14)	0.0611 (15)	0.0812 (17)	0.0157 (12)	0.0284 (13)	0.0325 (13)
C8	0.0191 (7)	0.0424 (10)	0.0295 (8)	0.0041 (6)	0.0091 (6)	0.0049 (7)
C9	0.0231 (7)	0.0430 (10)	0.0347 (8)	−0.0027 (7)	0.0123 (6)	−0.0018 (7)
C10	0.0259 (8)	0.0443 (10)	0.0453 (10)	−0.0067 (7)	0.0169 (7)	−0.0082 (8)
C11	0.0255 (7)	0.0378 (9)	0.0317 (8)	−0.0023 (6)	0.0133 (6)	−0.0064 (7)
N1	0.0261 (7)	0.0411 (9)	0.0323 (8)	−0.0005 (6)	0.0129 (6)	−0.0015 (6)
O1	0.0312 (6)	0.0538 (8)	0.0394 (7)	0.0036 (5)	0.0184 (5)	−0.0043 (6)
O2	0.0219 (5)	0.0758 (10)	0.0357 (7)	−0.0091 (6)	0.0101 (5)	−0.0050 (6)
O3	0.0270 (6)	0.0840 (11)	0.0446 (7)	0.0028 (6)	0.0156 (5)	0.0187 (7)
O4	0.0343 (7)	0.0718 (10)	0.0437 (7)	0.0051 (6)	0.0145 (5)	0.0159 (7)
O5	0.0247 (6)	0.0522 (8)	0.0472 (7)	−0.0080 (5)	0.0152 (5)	−0.0180 (6)

Geometric parameters (Å, º)

C1—C6	1.375 (3)	C8—O2	1.2596 (19)
C1—C2	1.377 (3)	C8—C9	1.530 (2)
C1—C7	1.503 (3)	C9—O5	1.4155 (19)
C2—C3	1.378 (3)	C9—C10	1.508 (2)
C2—H2	0.9300	C9—H9	0.9800
C3—C4	1.368 (2)	C10—C11	1.512 (2)
C3—H3	0.9300	C10—H10A	0.9700
C4—C5	1.371 (3)	C10—H10B	0.9700
C4—N1	1.458 (2)	C11—O4	1.200 (2)
C5—C6	1.382 (3)	C11—O3	1.302 (2)
C5—H5	0.9300	N1—H1A	0.868 (9)
C6—H6	0.9300	N1—H1B	0.868 (9)
C7—H7A	0.9600	N1—H1C	0.869 (9)
C7—H7B	0.9600	O3—H3A	0.831 (10)
C7—H7C	0.9600	O5—H5A	0.816 (10)
C8—O1	1.2357 (19)
C6—C1—C2	117.62 (18)	O1—C8—C9	117.47 (14)
C6—C1—C7	121.3 (2)	O2—C8—C9	116.00 (14)
C2—C1—C7	121.06 (19)	O5—C9—C10	109.40 (13)
C1—C2—C3	121.37 (18)	O5—C9—C8	110.47 (13)
C1—C2—H2	119.3	C10—C9—C8	112.47 (14)
C3—C2—H2	119.3	O5—C9—H9	108.1
C4—C3—C2	119.60 (17)	C10—C9—H9	108.1
C4—C3—H3	120.2	C8—C9—H9	108.1
C2—C3—H3	120.2	C9—C10—C11	108.84 (14)
C3—C4—C5	120.66 (17)	C9—C10—H10A	109.9
C3—C4—N1	119.05 (15)	C11—C10—H10A	109.9
C5—C4—N1	120.28 (15)	C9—C10—H10B	109.9
C4—C5—C6	118.69 (17)	C11—C10—H10B	109.9
C4—C5—H5	120.7	H10A—C10—H10B	108.3
C6—C5—H5	120.7	O4—C11—O3	123.16 (14)
C1—C6—C5	122.06 (19)	O4—C11—C10	123.35 (15)
C1—C6—H6	119.0	O3—C11—C10	113.45 (15)
C5—C6—H6	119.0	C4—N1—H1A	107.0 (14)
C1—C7—H7A	109.5	C4—N1—H1B	109.3 (14)
C1—C7—H7B	109.5	H1A—N1—H1B	112 (2)
H7A—C7—H7B	109.5	C4—N1—H1C	111.8 (15)
C1—C7—H7C	109.5	H1A—N1—H1C	111 (2)
H7A—C7—H7C	109.5	H1B—N1—H1C	105.1 (19)
H7B—C7—H7C	109.5	C11—O3—H3A	108.4 (19)
O1—C8—O2	126.49 (14)	C9—O5—H5A	107 (2)
C6—C1—C2—C3	−0.6 (3)	C4—C5—C6—C1	0.1 (3)
C7—C1—C2—C3	179.1 (2)	O1—C8—C9—O5	−7.5 (2)
C1—C2—C3—C4	0.3 (3)	O2—C8—C9—O5	174.38 (14)
C2—C3—C4—C5	0.2 (3)	O1—C8—C9—C10	−130.05 (16)
C2—C3—C4—N1	179.61 (17)	O2—C8—C9—C10	51.8 (2)
C3—C4—C5—C6	−0.4 (3)	O5—C9—C10—C11	58.19 (18)
N1—C4—C5—C6	−179.80 (17)	C8—C9—C10—C11	−178.66 (13)
C2—C1—C6—C5	0.3 (3)	C9—C10—C11—O4	69.8 (2)
C7—C1—C6—C5	−179.3 (2)	C9—C10—C11—O3	−107.77 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O1	0.82 (1)	2.12 (3)	2.6101 (15)	119 (2)
N1—H1A···O5	0.87 (1)	1.98 (1)	2.8381 (18)	172 (2)
N1—H1B···O1^i	0.87 (1)	1.88 (1)	2.7328 (18)	168 (2)
N1—H1C···O2^ii	0.87 (1)	2.01 (1)	2.8736 (19)	170 (2)
O3—H3A···O2^i	0.83 (1)	1.75 (1)	2.5830 (16)	179 (3)
O5—H5A···O4^iii	0.82 (1)	2.26 (2)	2.8088 (18)	125 (2)

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