N-Methyl­serotonin hydrogen oxalate

The solid-state structure of N-methyl­serotonin {systematic name: [2-(5-hy­droxy-1H-indol-3-yl)eth­yl](meth­yl)aza­nium hydrogen oxalate}, C₁₁H₁₅N₂O⁺·C₂HO₄⁻, is reported. The structure possesses a singly protonated N-methylserotonin cation and one hydrogen oxalate anion in the asymmetric unit. In the crystal, the mol­ecules are linked by N—H...O and O—H...O hydrogen bonds into a three-dimensional network.

Key indicators

Structure: I

• Single-crystal X-ray study
• T = 300 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.030
• wR factor = 0.077
• Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax < 18) ........       6.79 Note
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....        2.9 Note

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          5 Note
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          2 Report
PLAT802_ALERT_4_G CIF Input Record(s) with more than 80 Characters          1 Info
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          5 Note
PLAT883_ALERT_1_G No Info/Value for _atom_sites_solution_primary .     Please Do !
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min).          2 Note
PLAT933_ALERT_2_G Number of HKL-OMIT Records in Embedded .res File          1 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          3 Info

   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
   8 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
   3 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX4 (Bruker, 2021); cell refinement: SAINT (Bruker, 2021); data reduction: SAINT (Bruker, 2021); program(s) used to solve structure: SHELXT2014 (Sheldrick 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

[2-(5-Hydroxy-1H-indol-3-yl)ethyl](methyl)azanium hydrogen oxalate

Crystal data

C11H15N2O^+·C2HO4^−	F(000) = 296
Mr = 280.28	Dx = 1.394 Mg m^−3
Monoclinic, Pn	Mo Kα radiation, λ = 0.71073 Å
a = 5.7044 (4) Å	Cell parameters from 9870 reflections
b = 9.9485 (7) Å	θ = 2.7–26.4°
c = 11.7687 (7) Å	µ = 0.11 mm^−1
β = 90.321 (2)°	T = 300 K
V = 667.87 (8) Å^3	Block, brown
Z = 2	0.30 × 0.22 × 0.06 mm

Data collection

Bruker D8 Venture CMOS diffractometer	2670 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.032
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θmax = 26.4°, θmin = 3.5°
Tmin = 0.715, Tmax = 0.745	h = −7→7
29160 measured reflections	k = −12→12
2730 independent reflections	l = −14→14

Refinement

Refinement on F^2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.030	w = 1/[σ^2(Fo^2) + (0.0456P)^2 + 0.0849P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.077	(Δ/σ)max < 0.001
S = 1.10	Δρmax = 0.12 e Å^−3
2730 reflections	Δρmin = −0.21 e Å^−3
202 parameters	Absolute structure: Flack x determined using 1280 quotients [(I^+)-(I^-)]/[(I^+)+(I^-)] (Parsons et al., 2013)
5 restraints	Absolute structure parameter: −0.2 (2)

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.

Refinement. Hydrogen atoms H1, H1A, H2A, H2B and H5 were found in a difference-Fourier map. These H atoms were refined isotropically, using DFIX restraints with N–H(indole) distances of 0.87 (1) Å and N–H(ammonium) distances of 0.90 (1) Å. Isotropic displacement parameters were set to 1.2U_eq of the parent nitrogen atoms and 1.5U_eq of the parent oxygen atoms. All other H atoms were placed in calculated positions [C—H = 0.93 Å (sp²), 0.97 Å (CH₂), 0.96 Å (CH₃)].

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

	x	y	z	Uiso*/Ueq
O1	0.6078 (3)	0.04614 (17)	0.56240 (16)	0.0420 (4)
N1	0.4085 (4)	0.5480 (2)	0.39536 (18)	0.0393 (5)
N2	−0.1882 (3)	0.1720 (2)	0.12931 (17)	0.0349 (4)
C1	0.2113 (5)	0.5182 (2)	0.3334 (2)	0.0380 (5)
H1B	0.127417	0.579809	0.289859	0.046*
C2	0.4845 (4)	0.4328 (2)	0.44898 (18)	0.0300 (4)
C3	0.6748 (4)	0.4108 (2)	0.5213 (2)	0.0354 (5)
H3	0.772969	0.480992	0.543043	0.043*
C4	0.7131 (4)	0.2820 (2)	0.55953 (19)	0.0349 (5)
H4	0.840919	0.264578	0.606681	0.042*
C5	0.5629 (4)	0.1764 (2)	0.52871 (19)	0.0324 (5)
C6	0.3690 (4)	0.1982 (2)	0.46036 (19)	0.0312 (4)
H6	0.267239	0.128191	0.442551	0.037*
C7	0.3287 (4)	0.3280 (2)	0.41840 (18)	0.0286 (4)
C8	0.1551 (4)	0.3856 (2)	0.34432 (18)	0.0322 (5)
C9	−0.0508 (4)	0.3163 (3)	0.29002 (19)	0.0357 (5)
H9A	−0.170818	0.382400	0.272639	0.043*
H9B	−0.116215	0.252428	0.343399	0.043*
C10	0.0157 (4)	0.2435 (2)	0.18230 (19)	0.0307 (4)
H10A	0.078092	0.307744	0.128362	0.037*
H10B	0.138068	0.178790	0.199422	0.037*
C11	−0.3888 (4)	0.2595 (3)	0.1022 (2)	0.0506 (7)
H11A	−0.495409	0.212713	0.052715	0.076*
H11B	−0.333959	0.339444	0.065125	0.076*
H11C	−0.468021	0.283580	0.171023	0.076*
C12	0.4759 (3)	0.9157 (2)	0.30591 (18)	0.0279 (4)
C13	0.7233 (4)	0.8699 (2)	0.34523 (19)	0.0291 (4)
O2	0.3103 (3)	0.86964 (18)	0.36400 (16)	0.0392 (4)
O3	0.4636 (3)	0.98887 (17)	0.22060 (15)	0.0390 (4)
O4	0.7505 (3)	0.76747 (19)	0.39757 (19)	0.0493 (5)
O5	0.8902 (3)	0.95034 (18)	0.31279 (16)	0.0389 (4)
H1A	0.487 (5)	0.623 (2)	0.399 (3)	0.054 (9)*
H2A	−0.142 (5)	0.135 (3)	0.0625 (17)	0.046 (8)*
H2B	−0.234 (6)	0.107 (2)	0.177 (2)	0.048 (8)*
H1	0.715 (7)	0.040 (3)	0.602 (3)	0.054 (10)*
H5	1.024 (7)	0.922 (4)	0.330 (3)	0.067 (11)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0454 (10)	0.0325 (9)	0.0478 (10)	−0.0060 (8)	−0.0167 (8)	0.0050 (7)
N1	0.0501 (12)	0.0251 (9)	0.0427 (11)	−0.0081 (9)	0.0002 (9)	−0.0014 (8)
N2	0.0249 (9)	0.0442 (11)	0.0355 (10)	−0.0037 (8)	0.0011 (7)	−0.0082 (9)
C1	0.0485 (13)	0.0315 (11)	0.0341 (11)	0.0033 (10)	−0.0005 (9)	0.0013 (9)
C2	0.0357 (11)	0.0251 (9)	0.0292 (10)	−0.0062 (9)	0.0059 (8)	−0.0047 (8)
C3	0.0379 (12)	0.0342 (11)	0.0342 (11)	−0.0142 (9)	0.0012 (9)	−0.0113 (9)
C4	0.0338 (11)	0.0405 (12)	0.0304 (10)	−0.0041 (9)	−0.0042 (8)	−0.0043 (9)
C5	0.0354 (11)	0.0303 (11)	0.0314 (10)	−0.0034 (9)	−0.0001 (8)	−0.0009 (8)
C6	0.0325 (11)	0.0268 (10)	0.0344 (11)	−0.0084 (9)	−0.0008 (8)	−0.0027 (8)
C7	0.0298 (10)	0.0276 (10)	0.0282 (9)	−0.0035 (8)	0.0028 (8)	−0.0054 (8)
C8	0.0347 (11)	0.0329 (11)	0.0292 (10)	0.0007 (9)	0.0010 (8)	−0.0043 (9)
C9	0.0301 (11)	0.0427 (12)	0.0344 (11)	−0.0006 (9)	0.0001 (9)	−0.0059 (9)
C10	0.0223 (9)	0.0335 (10)	0.0364 (11)	−0.0011 (8)	0.0000 (8)	−0.0040 (8)
C11	0.0285 (12)	0.074 (2)	0.0487 (15)	0.0014 (12)	−0.0078 (10)	0.0122 (13)
C12	0.0192 (9)	0.0255 (9)	0.0389 (11)	−0.0006 (7)	−0.0053 (8)	−0.0010 (9)
C13	0.0215 (9)	0.0296 (10)	0.0361 (10)	−0.0024 (8)	−0.0052 (7)	0.0010 (9)
O2	0.0187 (7)	0.0423 (9)	0.0567 (10)	−0.0034 (6)	−0.0011 (7)	0.0103 (8)
O3	0.0264 (7)	0.0443 (9)	0.0463 (9)	−0.0007 (7)	−0.0098 (6)	0.0118 (8)
O4	0.0290 (8)	0.0397 (10)	0.0790 (13)	−0.0060 (7)	−0.0172 (8)	0.0244 (9)
O5	0.0170 (7)	0.0445 (10)	0.0554 (10)	−0.0019 (6)	−0.0011 (7)	0.0172 (8)

Geometric parameters (Å, º)

O1—C5	1.378 (3)	C6—H6	0.9300
O1—H1	0.77 (4)	C6—C7	1.401 (3)
N1—C1	1.370 (3)	C7—C8	1.435 (3)
N1—C2	1.377 (3)	C8—C9	1.501 (3)
N1—H1A	0.873 (14)	C9—H9A	0.9700
N2—C10	1.496 (3)	C9—H9B	0.9700
N2—C11	1.472 (3)	C9—C10	1.510 (3)
N2—H2A	0.910 (14)	C10—H10A	0.9700
N2—H2B	0.898 (14)	C10—H10B	0.9700
C1—H1B	0.9300	C11—H11A	0.9600
C1—C8	1.363 (3)	C11—H11B	0.9600
C2—C3	1.393 (3)	C11—H11C	0.9600
C2—C7	1.415 (3)	C12—C13	1.551 (3)
C3—H3	0.9300	C12—O2	1.256 (3)
C3—C4	1.375 (4)	C12—O3	1.242 (3)
C4—H4	0.9300	C13—O4	1.200 (3)
C4—C5	1.402 (3)	C13—O5	1.303 (3)
C5—C6	1.381 (3)	O5—H5	0.84 (4)
C5—O1—H1	113 (3)	C6—C7—C8	133.9 (2)
C1—N1—C2	108.64 (19)	C1—C8—C7	106.3 (2)
C1—N1—H1A	129 (2)	C1—C8—C9	126.0 (2)
C2—N1—H1A	122 (2)	C7—C8—C9	127.6 (2)
C10—N2—H2A	109 (2)	C8—C9—H9A	109.2
C10—N2—H2B	108 (2)	C8—C9—H9B	109.2
C11—N2—C10	114.2 (2)	C8—C9—C10	112.22 (18)
C11—N2—H2A	106.4 (19)	H9A—C9—H9B	107.9
C11—N2—H2B	109 (2)	C10—C9—H9A	109.2
H2A—N2—H2B	110 (3)	C10—C9—H9B	109.2
N1—C1—H1B	124.7	N2—C10—C9	112.32 (17)
C8—C1—N1	110.6 (2)	N2—C10—H10A	109.1
C8—C1—H1B	124.7	N2—C10—H10B	109.1
N1—C2—C3	130.8 (2)	C9—C10—H10A	109.1
N1—C2—C7	107.5 (2)	C9—C10—H10B	109.1
C3—C2—C7	121.7 (2)	H10A—C10—H10B	107.9
C2—C3—H3	121.0	N2—C11—H11A	109.5
C4—C3—C2	117.9 (2)	N2—C11—H11B	109.5
C4—C3—H3	121.0	N2—C11—H11C	109.5
C3—C4—H4	119.4	H11A—C11—H11B	109.5
C3—C4—C5	121.2 (2)	H11A—C11—H11C	109.5
C5—C4—H4	119.4	H11B—C11—H11C	109.5
O1—C5—C4	121.2 (2)	O2—C12—C13	114.59 (18)
O1—C5—C6	117.5 (2)	O3—C12—C13	117.46 (18)
C6—C5—C4	121.3 (2)	O3—C12—O2	127.91 (19)
C5—C6—H6	120.7	O4—C13—C12	121.18 (19)
C5—C6—C7	118.7 (2)	O4—C13—O5	125.39 (19)
C7—C6—H6	120.7	O5—C13—C12	113.40 (18)
C2—C7—C8	106.89 (19)	C13—O5—H5	113 (3)
C6—C7—C2	119.2 (2)
O1—C5—C6—C7	−175.6 (2)	C3—C4—C5—O1	176.8 (2)
N1—C1—C8—C7	0.1 (3)	C3—C4—C5—C6	−1.1 (3)
N1—C1—C8—C9	179.3 (2)	C4—C5—C6—C7	2.3 (3)
N1—C2—C3—C4	−177.7 (2)	C5—C6—C7—C2	−1.2 (3)
N1—C2—C7—C6	178.9 (2)	C5—C6—C7—C8	177.6 (2)
N1—C2—C7—C8	−0.2 (2)	C6—C7—C8—C1	−178.9 (3)
C1—N1—C2—C3	−179.7 (2)	C6—C7—C8—C9	1.9 (4)
C1—N1—C2—C7	0.3 (3)	C7—C2—C3—C4	2.3 (3)
C1—C8—C9—C10	97.9 (3)	C7—C8—C9—C10	−83.1 (3)
C2—N1—C1—C8	−0.2 (3)	C8—C9—C10—N2	178.81 (19)
C2—C3—C4—C5	−1.3 (3)	C11—N2—C10—C9	57.2 (3)
C2—C7—C8—C1	0.1 (2)	O2—C12—C13—O4	24.3 (3)
C2—C7—C8—C9	−179.1 (2)	O2—C12—C13—O5	−157.6 (2)
C3—C2—C7—C6	−1.1 (3)	O3—C12—C13—O4	−153.7 (2)
C3—C2—C7—C8	179.8 (2)	O3—C12—C13—O5	24.4 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4	0.87 (1)	2.08 (2)	2.928 (3)	164 (3)
N2—H2A···O1^i	0.91 (1)	2.30 (3)	2.862 (3)	120 (2)
N2—H2A···O2^ii	0.91 (1)	2.35 (2)	3.150 (3)	147 (3)
N2—H2B···O3^iii	0.90 (1)	2.15 (2)	2.906 (3)	141 (3)
N2—H2B···O5^iii	0.90 (1)	2.34 (2)	3.117 (3)	145 (3)
O1—H1···O3^iv	0.77 (4)	2.00 (4)	2.768 (2)	172 (4)
O5—H5···O2^v	0.84 (4)	1.76 (4)	2.595 (2)	177 (4)

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