Bis(4-acet­oxy-N,N-di­methyl­tryptammonium) fumarate: a new crystalline form of psilacetin, an alternative to psilocybin as a psilocin prodrug

The title compound has a single protonated psilacetin cation and one half of a fumarate dianion in the asymmetric unit. The ions are held together through N—H...O hydrogen bonds in infinite one-dimensional chains along [111].

Key indicators

• Single-crystal X-ray study
• T = 200 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.045
• wR factor = 0.110
• Data-to-parameter ratio = 13.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Low    'MainMol' Ueq as Compared to Neighbors of         N2 Check
PLAT906_ALERT_3_C Large K Value in the Analysis of Variance ......      2.657 Check
PLAT910_ALERT_3_C Missing # of FCF Reflection(s) Below Theta(Min).          6 Note

Alert level G
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ     Please Check
PLAT045_ALERT_1_G Calculated and Reported Z Differ by a Factor ...       2.00 Check
PLAT154_ALERT_1_G The s.u.'s on the Cell Angles are Equal ..(Note)      0.005 Degree
PLAT300_ALERT_4_G Atom Site Occupancy of H1A        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1B        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1C        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1D        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1E        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1F        Constrained at        0.5 Check
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          5 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          1 Info

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

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   7 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Bis{2-[4-(acetyloxy)-1H-indol-3-yl]ethan-1-aminium} but-2-enedioate

Crystal data

2C14H19N2O2^+·C4H2O4^2^−	Z = 1
Mr = 608.68	F(000) = 324
Triclinic, P1	Dx = 1.289 Mg m^−3
a = 8.3965 (13) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.9879 (14) Å	Cell parameters from 6407 reflections
c = 12.0126 (16) Å	θ = 3.3–25.1°
α = 101.730 (5)°	µ = 0.09 mm^−1
β = 100.818 (5)°	T = 200 K
γ = 112.463 (5)°	BLOCK, colourless
V = 784.2 (2) Å^3	0.19 × 0.16 × 0.13 mm

Data collection

Bruker D8 Venture CMOS diffractometer	2087 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.056
Absorption correction: multi-scan (SADABS; Bruker, 2016)	θmax = 25.4°, θmin = 3.3°
Tmin = 0.714, Tmax = 0.745	h = −10→10
21581 measured reflections	k = −10→10
2877 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)] = 0.045	w = 1/[σ^2(Fo^2) + (0.0387P)^2 + 0.3852P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.110	(Δ/σ)max < 0.001
S = 1.03	Δρmax = 0.26 e Å^−3
2877 reflections	Δρmin = −0.20 e Å^−3
210 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.050 (4)

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	Occ. (<1)
O1	0.0322 (2)	0.33780 (19)	0.50722 (14)	0.0539 (4)
O2	0.30616 (18)	0.46535 (16)	0.48485 (12)	0.0413 (4)
O3	0.6497 (2)	0.3361 (2)	1.04226 (12)	0.0597 (5)
O4	0.69101 (17)	0.29711 (17)	0.86294 (11)	0.0386 (4)
N1	0.2368 (2)	−0.0732 (2)	0.29315 (15)	0.0412 (4)
N2	0.3416 (2)	0.1243 (2)	0.79890 (13)	0.0375 (4)
C1	0.2567 (4)	0.5920 (3)	0.6569 (2)	0.0578 (6)
H1A	0.3818	0.6670	0.6650	0.087*	0.5
H1B	0.1847	0.6558	0.6561	0.087*	0.5
H1C	0.2531	0.5457	0.7240	0.087*	0.5
H1D	0.1646	0.5787	0.6984	0.087*	0.5
H1E	0.3617	0.5899	0.7073	0.087*	0.5
H1F	0.2933	0.7000	0.6394	0.087*	0.5
C2	0.1817 (3)	0.4512 (3)	0.54365 (18)	0.0406 (5)
C3	0.2616 (3)	0.3380 (2)	0.37872 (17)	0.0367 (5)
C4	0.2330 (3)	0.3748 (3)	0.27365 (19)	0.0482 (6)
H4	0.2329	0.4804	0.2735	0.058*
C5	0.2040 (3)	0.2580 (3)	0.1667 (2)	0.0572 (7)
H5	0.1839	0.2852	0.0945	0.069*
C6	0.2041 (3)	0.1050 (3)	0.16395 (18)	0.0491 (6)
H6	0.1855	0.0261	0.0912	0.059*
C7	0.2325 (2)	0.0689 (3)	0.27162 (16)	0.0361 (5)
C8	0.2611 (2)	0.1833 (2)	0.38128 (15)	0.0324 (4)
C9	0.2860 (3)	0.1039 (2)	0.47124 (16)	0.0378 (5)
C10	0.2697 (3)	−0.0505 (3)	0.41319 (17)	0.0428 (5)
H10	0.2796	−0.1313	0.4506	0.051*
C11	0.3232 (4)	0.1765 (3)	0.60302 (17)	0.0552 (7)
H11A	0.4523	0.2569	0.6377	0.066*
H11B	0.2518	0.2408	0.6160	0.066*
C12	0.2802 (3)	0.0483 (3)	0.66691 (16)	0.0446 (6)
H12A	0.3380	−0.0264	0.6453	0.054*
H12B	0.1482	−0.0222	0.6407	0.054*
C13	0.3087 (4)	−0.0104 (3)	0.8580 (2)	0.0623 (7)
H13A	0.3654	−0.0819	0.8298	0.094*
H13B	0.1786	−0.0794	0.8389	0.094*
H13C	0.3603	0.0415	0.9443	0.094*
C14	0.2660 (3)	0.2400 (4)	0.84318 (19)	0.0610 (7)
H14A	0.3073	0.2793	0.9303	0.092*
H14B	0.1341	0.1804	0.8159	0.092*
H14C	0.3063	0.3371	0.8128	0.092*
C15	0.9426 (3)	0.4767 (2)	1.03029 (16)	0.0346 (5)
H15	0.9873	0.5193	1.1146	0.042*
C16	0.7463 (3)	0.3612 (2)	0.97637 (16)	0.0340 (5)
H1	0.240 (3)	−0.159 (3)	0.242 (2)	0.055 (7)*
H2	0.475 (3)	0.191 (3)	0.8236 (18)	0.048 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0506 (10)	0.0427 (9)	0.0626 (10)	0.0148 (8)	0.0223 (8)	0.0098 (8)
O2	0.0381 (8)	0.0330 (8)	0.0418 (8)	0.0099 (6)	0.0069 (6)	0.0048 (6)
O3	0.0445 (9)	0.0788 (12)	0.0310 (8)	0.0068 (8)	0.0124 (7)	0.0053 (8)
O4	0.0332 (8)	0.0447 (8)	0.0248 (7)	0.0120 (6)	0.0032 (6)	−0.0008 (6)
N1	0.0449 (11)	0.0422 (11)	0.0307 (9)	0.0198 (9)	0.0081 (8)	0.0003 (8)
N2	0.0323 (9)	0.0398 (10)	0.0267 (8)	0.0065 (8)	0.0070 (7)	0.0022 (7)
C1	0.0716 (17)	0.0518 (14)	0.0449 (13)	0.0323 (13)	0.0071 (12)	0.0028 (11)
C2	0.0472 (13)	0.0356 (12)	0.0406 (12)	0.0208 (11)	0.0097 (10)	0.0125 (9)
C3	0.0318 (11)	0.0356 (11)	0.0347 (11)	0.0086 (9)	0.0082 (8)	0.0083 (9)
C4	0.0514 (14)	0.0464 (13)	0.0463 (13)	0.0165 (11)	0.0143 (10)	0.0230 (11)
C5	0.0671 (16)	0.0699 (17)	0.0386 (13)	0.0257 (13)	0.0204 (11)	0.0283 (12)
C6	0.0501 (13)	0.0634 (16)	0.0291 (11)	0.0189 (12)	0.0169 (10)	0.0114 (10)
C7	0.0287 (10)	0.0423 (12)	0.0308 (10)	0.0106 (9)	0.0097 (8)	0.0070 (9)
C8	0.0254 (10)	0.0364 (11)	0.0270 (9)	0.0082 (8)	0.0050 (7)	0.0055 (8)
C9	0.0436 (12)	0.0359 (11)	0.0269 (10)	0.0170 (9)	0.0019 (8)	0.0036 (8)
C10	0.0511 (13)	0.0416 (12)	0.0306 (11)	0.0217 (10)	0.0034 (9)	0.0055 (9)
C11	0.0909 (19)	0.0408 (13)	0.0269 (11)	0.0334 (13)	−0.0004 (11)	0.0031 (9)
C12	0.0386 (12)	0.0459 (13)	0.0265 (10)	0.0036 (10)	0.0053 (9)	−0.0018 (9)
C13	0.0717 (17)	0.0533 (15)	0.0392 (12)	0.0026 (13)	0.0183 (12)	0.0149 (11)
C14	0.0548 (15)	0.091 (2)	0.0379 (12)	0.0421 (14)	0.0129 (11)	0.0014 (12)
C15	0.0373 (11)	0.0371 (11)	0.0228 (9)	0.0151 (9)	0.0025 (7)	0.0037 (8)
C16	0.0372 (11)	0.0350 (11)	0.0267 (10)	0.0159 (9)	0.0065 (8)	0.0056 (8)

Geometric parameters (Å, º)

O1—C2	1.200 (2)	C5—H5	0.9500
O2—C2	1.349 (2)	C5—C6	1.369 (3)
O2—C3	1.405 (2)	C6—H6	0.9500
O3—C16	1.228 (2)	C6—C7	1.396 (3)
O4—C16	1.282 (2)	C7—C8	1.412 (3)
N1—C7	1.365 (3)	C8—C9	1.437 (3)
N1—C10	1.373 (3)	C9—C10	1.362 (3)
N1—H1	0.90 (2)	C9—C11	1.506 (3)
N2—C12	1.493 (2)	C10—H10	0.9500
N2—C13	1.488 (3)	C11—H11A	0.9900
N2—C14	1.475 (3)	C11—H11B	0.9900
N2—H2	0.99 (2)	C11—C12	1.480 (3)
C1—H1A	0.9800	C12—H12A	0.9900
C1—H1B	0.9800	C12—H12B	0.9900
C1—H1C	0.9800	C13—H13A	0.9800
C1—H1D	0.9800	C13—H13B	0.9800
C1—H1E	0.9800	C13—H13C	0.9800
C1—H1F	0.9800	C14—H14A	0.9800
C1—C2	1.489 (3)	C14—H14B	0.9800
C3—C4	1.370 (3)	C14—H14C	0.9800
C3—C8	1.396 (3)	C15—C15^i	1.309 (4)
C4—H4	0.9500	C15—H15	0.9500
C4—C5	1.397 (3)	C15—C16	1.494 (3)
C2—O2—C3	118.62 (15)	C5—C6—C7	117.8 (2)
C7—N1—C10	108.50 (17)	C7—C6—H6	121.1
C7—N1—H1	126.7 (15)	N1—C7—C6	129.45 (19)
C10—N1—H1	123.8 (15)	N1—C7—C8	107.93 (17)
C12—N2—H2	107.7 (12)	C6—C7—C8	122.6 (2)
C13—N2—C12	110.37 (16)	C3—C8—C7	117.04 (17)
C13—N2—H2	105.4 (12)	C3—C8—C9	136.10 (17)
C14—N2—C12	114.55 (17)	C7—C8—C9	106.85 (17)
C14—N2—C13	111.26 (18)	C8—C9—C11	127.06 (18)
C14—N2—H2	107.1 (12)	C10—C9—C8	106.02 (16)
H1A—C1—H1B	109.5	C10—C9—C11	126.91 (18)
H1A—C1—H1C	109.5	N1—C10—H10	124.7
H1A—C1—H1D	141.1	C9—C10—N1	110.70 (19)
H1A—C1—H1E	56.3	C9—C10—H10	124.7
H1A—C1—H1F	56.3	C9—C11—H11A	108.7
H1B—C1—H1C	109.5	C9—C11—H11B	108.7
H1B—C1—H1D	56.3	H11A—C11—H11B	107.6
H1B—C1—H1E	141.1	C12—C11—C9	114.06 (17)
H1B—C1—H1F	56.3	C12—C11—H11A	108.7
H1C—C1—H1D	56.3	C12—C11—H11B	108.7
H1C—C1—H1E	56.3	N2—C12—H12A	109.0
H1C—C1—H1F	141.1	N2—C12—H12B	109.0
H1D—C1—H1E	109.5	C11—C12—N2	112.99 (16)
H1D—C1—H1F	109.5	C11—C12—H12A	109.0
H1E—C1—H1F	109.5	C11—C12—H12B	109.0
C2—C1—H1A	109.5	H12A—C12—H12B	107.8
C2—C1—H1B	109.5	N2—C13—H13A	109.5
C2—C1—H1C	109.5	N2—C13—H13B	109.5
C2—C1—H1D	109.5	N2—C13—H13C	109.5
C2—C1—H1E	109.5	H13A—C13—H13B	109.5
C2—C1—H1F	109.5	H13A—C13—H13C	109.5
O1—C2—O2	122.94 (19)	H13B—C13—H13C	109.5
O1—C2—C1	126.3 (2)	N2—C14—H14A	109.5
O2—C2—C1	110.81 (19)	N2—C14—H14B	109.5
C4—C3—O2	118.17 (19)	N2—C14—H14C	109.5
C4—C3—C8	120.95 (19)	H14A—C14—H14B	109.5
C8—C3—O2	120.68 (17)	H14A—C14—H14C	109.5
C3—C4—H4	119.8	H14B—C14—H14C	109.5
C3—C4—C5	120.4 (2)	C15^i—C15—H15	117.7
C5—C4—H4	119.8	C15^i—C15—C16	124.7 (2)
C4—C5—H5	119.4	C16—C15—H15	117.7
C6—C5—C4	121.2 (2)	O3—C16—O4	124.80 (18)
C6—C5—H5	119.4	O3—C16—C15	118.60 (16)
C5—C6—H6	121.1	O4—C16—C15	116.59 (16)
O2—C3—C4—C5	174.36 (19)	C6—C7—C8—C3	−0.6 (3)
O2—C3—C8—C7	−173.84 (16)	C6—C7—C8—C9	−179.64 (19)
O2—C3—C8—C9	4.9 (3)	C7—N1—C10—C9	0.4 (2)
N1—C7—C8—C3	−179.97 (16)	C7—C8—C9—C10	−0.7 (2)
N1—C7—C8—C9	1.0 (2)	C7—C8—C9—C11	179.2 (2)
C2—O2—C3—C4	107.9 (2)	C8—C3—C4—C5	−0.5 (3)
C2—O2—C3—C8	−77.2 (2)	C8—C9—C10—N1	0.2 (2)
C3—O2—C2—O1	−2.8 (3)	C8—C9—C11—C12	159.8 (2)
C3—O2—C2—C1	176.73 (17)	C9—C11—C12—N2	172.04 (19)
C3—C4—C5—C6	−0.3 (4)	C10—N1—C7—C6	179.8 (2)
C3—C8—C9—C10	−179.5 (2)	C10—N1—C7—C8	−0.8 (2)
C3—C8—C9—C11	0.3 (4)	C10—C9—C11—C12	−20.4 (4)
C4—C3—C8—C7	0.9 (3)	C11—C9—C10—N1	−179.7 (2)
C4—C3—C8—C9	179.6 (2)	C13—N2—C12—C11	−175.2 (2)
C4—C5—C6—C7	0.6 (3)	C14—N2—C12—C11	58.3 (3)
C5—C6—C7—N1	179.1 (2)	C15^i—C15—C16—O3	−174.9 (3)
C5—C6—C7—C8	−0.2 (3)	C15^i—C15—C16—O4	4.1 (4)

Symmetry code: (i) −x+2, −y+1, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O4^ii	0.90 (2)	1.91 (2)	2.786 (2)	165 (2)
N2—H2···O4	0.99 (2)	1.61 (2)	2.607 (2)	179 (2)

Symmetry code: (ii) −x+1, −y, −z+1.