Diiso­propyl­ammonium hydrogen phthalate

Seye, D.; Diop, L.; Diop, C.A.K.; Geiger, D.K.

doi:10.1107/S2414314618007046

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 5| May 2018| x180704

https://doi.org/10.1107/S2414314618007046

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Diisopropylammonium hydrogen phthalate

Dame Seye,^a Libasse Diop,^a ^* Cheikh Abdoul Khadir Diop ^a and David K. Geiger ^b

^aLaboratoire de Chimie Minérale et Analytique, Département de Chimie, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal, and ^bDepartment of Chemistry, SUNY-College at Geneseo, Geneseo, NY 14454, USA
^*Correspondence e-mail: dlibasse@gmail.com

Edited by A. J. Lough, University of Toronto, Canada (Received 16 April 2018; accepted 8 May 2018; online 15 May 2018)

In the crystal of the title molecular salt, C₆H₁₆N⁺·C₈H₅O₄⁻, the cation and anions are linked into [010] chains by N—H⋯O hydrogen bonds. The chains are connected to their neighbours through weak C—H⋯O hydrogen bonds, leading to a layered supramolecular architecture. The hydrogen phthalate anion exhibits an intramolecular O—H⋯O hydrogen bond in which the H atom is approximately equidistant to the two O atoms.

Keywords: crystal structure; hydrogen bonds; layered structure.

CCDC reference: 1842128

Structure description

Various ammonium hydrogen phthalate and phthalate salts have been synthesized by several groups (Edwards et al., 2001 ; Pereira Silva et al., 2006 ; Yu, 2012 ; Liu 2012 ; Shahid et al. 2015 ; Lin et al. 2011 ). These salts can react with metallic halides leading to complexes (Ma et al., 2004 ; Askarinejad et al., 2006 ; Döring & Jones, 2016 ). For several years, our group has been involved in the study of the interactions of similar salts with organotin(IV) and halotin(IV) compounds (Diop et al., 2016 ; Sarr et al., 2018 ). As part of our ongoing studies in this area, we now describe the synthesis and structure of the title molecular salt.

The title compound crystallizes in the monoclinic P2₁/c space group with the asymmetric unit comprising of one diisopropylammonium cation and one hydrogen phthalate anion (Fig. 1). The C—C and C—N bonds within the cation are similar to those previously observed for compounds containing the iPr₂NH₂⁺ cation (Sarr et al., 2018; Lin et al., 2017 ). The C—C and C—O bonds of the hydrogen phthalate anion are close to the published values for salts containing this anion (Liu et al., 2012; Shahid et al., 2015). In the extended structure, the monomeric acidic inner (O1—H1⋯O3) hydrogen-bonded anions [PhCO₂H(COO)]⁻ are connected to the cations via hydrogen bonds (N1—H1A⋯O4ⁱ, N1—H1B⋯O2; Table 1, Fig. 2), giving rise to zigzag chains of alternating cations and anions parallel to [010]. Weak intermolecular hydrogen bonds (C3—H3C⋯O1, C13—H13⋯O1, C12—H12⋯O3, C3—H3A⋯O4 and C6—H6⋯O2), which can be described as phthalate/phthalate and phthalate/cation interactions, occur leading to a supramolecular pleated sheet architecture.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O⋯O3	1.19 (4)	1.20 (4)	2.385 (3)	173 (3)
N1—H1A⋯O4ⁱ	0.94 (3)	1.83 (3)	2.756 (3)	169 (2)
N1—H1B⋯O2	0.95 (3)	1.83 (3)	2.763 (2)	166 (2)
C3—H3C⋯O1	0.98	2.70	3.659 (3)	166
C3—H3A⋯O4ⁱ	0.98	2.69	3.392 (4)	129
C6—H6C⋯O2	0.98	2.68	3.408 (4)	132
C12—H12⋯O3ⁱⁱ	0.95	2.58	3.401 (2)	145
C13—H13⋯O1ⁱⁱ	0.95	2.61	3.449 (3)	148
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) x-1, y, z.

Figure 1
View of the title compound showing the atom-labelling scheme. Anisotropic displacement parameters of non-H atoms are drawn at the 50% probability level.

Figure 2
Partial packing diagram showing the hydrogen-bonding interactions. Only H atoms involved in the intermolecular interactions are shown. Symmetry identifiers: (a) −x + 1, y + $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (b) x + 1, y, z; (c) −x + 1, y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ .

A search of the Cambridge Structural Database (CSD Version 5.39, updates Nov 2017; Groom et al., 2016 ) yielded 67 hits for diisopropylammonium salts while 101 hits were obtained in a search for the phthalate anion.

Synthesis and crystallization

All the chemicals were purchased from Aldrich (Germany) and used without further purification. Diisopropylammonium hydrogen phthalate [iPr₂NH₂·Ph(CO₂H)(CO₂)] was obtained from the partial neutralization of phthalic acid (Ph(COH)₂); 5 g, 3 mmol) by diisopropylamine (iPr₂NH; 3.05 g, 3 mmol) in ethanol (50 ml). The clear mixture was stirred for two h. Crystals suitable for X-ray diffraction analysis were obtained after a week of slow solvent evaporation at room temperature (300 K).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₆H₁₆N⁺·C₈H₅O₄⁻
M_r	267.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	200
a, b, c (Å)	8.160 (3), 14.876 (5), 12.549 (5)
β (°)	93.192 (9)
V (Å³)	1520.9 (10)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.09
Crystal size (mm)	0.40 × 0.40 × 0.40

Data collection
Diffractometer	Bruker Smart X2S benchtop
Absorption correction	Multi-scan (SADABS; Bruker, 2013 )
T_min, T_max	0.48, 0.97
No. of measured, independent and observed [I > 2σ(I)] reflections	12641, 2772, 2240
R_int	0.071
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.164, 1.07
No. of reflections	2772
No. of parameters	188
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.23
Computer programs: APEX2 and SAINT (Bruker, 2013), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), PLATON (Spek, 2009 ), Mercury (Macrae et al., 2006 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1842128

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314618007046/lh5874sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618007046/lh5874Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618007046/lh5874Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Diisopropylammonium hydrogen phthalate top

Crystal data top

C₆H₁₆N⁺·C₈H₅O₄⁻	F(000) = 576
M_r = 267.32	D_x = 1.167 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.160 (3) Å	Cell parameters from 5881 reflections
b = 14.876 (5) Å	θ = 2.5–25.3°
c = 12.549 (5) Å	µ = 0.09 mm⁻¹
β = 93.192 (9)°	T = 200 K
V = 1520.9 (10) Å³	Block, colorless
Z = 4	0.40 × 0.40 × 0.40 mm

Data collection top

Bruker Smart X2S benchtop diffractometer	2772 independent reflections
Radiation source: sealed microfocus tube	2240 reflections with I > 2σ(I)
Detector resolution: 8.3330 pixels mm^-1	R_int = 0.071
ω scans	θ_max = 25.4°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2013)	h = −7→9
T_min = 0.48, T_max = 0.97	k = −17→16
12641 measured reflections	l = −15→15

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.057	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.164	w = 1/[σ²(F_o²) + (0.0729P)² + 0.612P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
2772 reflections	Δρ_max = 0.23 e Å⁻³
188 parameters	Δρ_min = −0.23 e Å⁻³

Special details top

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. All hydrogen atoms were observed in difference fourier maps. The H atoms were refined using a riding model with a C— H distance of 0.98 Å for the methyl carbon atoms and 0.95 Å for the phenyl carbon atoms. The methyl C—H hydrogen atom isotropic displacement parameters were set using the and hydrogen-atom isotropic displacement parameters were set using the approximation U_iso(H) = 1.2U_eq(C). The hydrogen atoms bonded to the oxygen and nitrogen atoms were refined freely, including isotropic displacement parameters.

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

	x	y	z	U_iso*/U_eq
O1	0.51102 (17)	0.44641 (14)	0.35313 (15)	0.0727 (6)
H1O	0.511 (4)	0.502 (2)	0.285 (3)	0.106 (11)*
O2	0.3436 (2)	0.36584 (14)	0.44266 (17)	0.0824 (6)
O3	0.50277 (17)	0.55055 (13)	0.20842 (16)	0.0687 (5)
O4	0.3243 (2)	0.61102 (16)	0.09499 (18)	0.0947 (8)
N1	0.51945 (19)	0.22605 (11)	0.53843 (13)	0.0386 (4)
H1A	0.559 (3)	0.1865 (17)	0.4879 (19)	0.059 (7)*
H1B	0.473 (3)	0.2747 (18)	0.4978 (19)	0.061 (7)*
C1	0.6655 (3)	0.26303 (15)	0.60386 (16)	0.0482 (5)
H1	0.6257	0.3097	0.6536	0.058*
C2	0.7504 (3)	0.1897 (2)	0.6693 (2)	0.0899 (11)
H2A	0.7802	0.1405	0.6221	0.135*
H2B	0.6764	0.167	0.7219	0.135*
H2C	0.8498	0.2139	0.7061	0.135*
C3	0.7788 (3)	0.30729 (17)	0.5290 (2)	0.0621 (6)
H3A	0.8208	0.2621	0.4807	0.093*
H3B	0.8708	0.3351	0.5703	0.093*
H3C	0.7186	0.3535	0.4872	0.093*
C4	0.3859 (2)	0.18111 (14)	0.59641 (17)	0.0466 (5)
H4	0.4352	0.1302	0.6392	0.056*
C5	0.2623 (3)	0.1430 (2)	0.5132 (2)	0.0690 (7)
H5A	0.215	0.192	0.4694	0.104*
H5B	0.1747	0.112	0.5491	0.104*
H5C	0.3174	0.1003	0.4677	0.104*
C6	0.3086 (3)	0.24578 (19)	0.6716 (2)	0.0703 (7)
H6A	0.3903	0.2641	0.7275	0.105*
H6B	0.2163	0.2163	0.7042	0.105*
H6C	0.2688	0.2989	0.6318	0.105*
C7	0.3676 (3)	0.42528 (14)	0.37800 (17)	0.0478 (5)
C8	0.3558 (2)	0.56711 (13)	0.17568 (18)	0.0456 (5)
C9	0.2187 (2)	0.47323 (12)	0.32552 (14)	0.0349 (4)
C10	0.2140 (2)	0.53271 (12)	0.23738 (15)	0.0352 (4)
C11	0.0605 (2)	0.56684 (14)	0.20079 (17)	0.0471 (5)
H11	0.0551	0.6057	0.1406	0.057*
C12	−0.0817 (2)	0.54627 (16)	0.24843 (19)	0.0546 (6)
H12	−0.1833	0.5709	0.2218	0.066*
C13	−0.0761 (2)	0.48961 (17)	0.33524 (19)	0.0541 (6)
H13	−0.1735	0.4755	0.3698	0.065*
C14	0.0725 (2)	0.45341 (14)	0.37176 (17)	0.0454 (5)
H14	0.0747	0.4134	0.4308	0.054*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0296 (8)	0.1033 (14)	0.0849 (12)	0.0125 (8)	0.0015 (8)	0.0280 (11)
O2	0.0646 (11)	0.0819 (13)	0.1007 (14)	0.0197 (9)	0.0037 (10)	0.0501 (11)
O3	0.0295 (8)	0.0905 (13)	0.0870 (12)	−0.0079 (7)	0.0117 (8)	0.0212 (10)
O4	0.0614 (11)	0.1140 (17)	0.1107 (15)	0.0077 (11)	0.0236 (11)	0.0737 (14)
N1	0.0379 (8)	0.0378 (9)	0.0399 (8)	0.0039 (7)	0.0005 (7)	−0.0007 (7)
C1	0.0480 (11)	0.0489 (12)	0.0470 (11)	−0.0057 (9)	−0.0030 (9)	−0.0059 (9)
C2	0.0626 (16)	0.112 (2)	0.092 (2)	−0.0162 (16)	−0.0300 (15)	0.0447 (19)
C3	0.0529 (13)	0.0613 (15)	0.0722 (15)	−0.0143 (11)	0.0049 (11)	0.0017 (12)
C4	0.0450 (11)	0.0441 (11)	0.0507 (11)	0.0002 (9)	0.0035 (9)	0.0058 (9)
C5	0.0527 (13)	0.0793 (18)	0.0743 (16)	−0.0156 (12)	−0.0026 (12)	−0.0062 (14)
C6	0.0672 (15)	0.0786 (18)	0.0678 (15)	−0.0016 (13)	0.0272 (13)	−0.0030 (14)
C7	0.0423 (11)	0.0489 (12)	0.0521 (11)	0.0105 (9)	0.0005 (9)	0.0048 (10)
C8	0.0378 (10)	0.0399 (10)	0.0600 (12)	−0.0010 (8)	0.0118 (9)	0.0041 (10)
C9	0.0291 (9)	0.0332 (9)	0.0423 (10)	0.0006 (7)	0.0000 (7)	−0.0015 (7)
C10	0.0283 (9)	0.0327 (9)	0.0445 (10)	−0.0001 (7)	0.0032 (7)	−0.0004 (7)
C11	0.0368 (10)	0.0512 (12)	0.0528 (11)	0.0052 (9)	−0.0028 (9)	0.0123 (10)
C12	0.0288 (10)	0.0684 (15)	0.0657 (14)	0.0047 (9)	−0.0054 (9)	0.0041 (11)
C13	0.0262 (9)	0.0707 (15)	0.0663 (13)	−0.0078 (9)	0.0099 (9)	0.0026 (12)
C14	0.0381 (10)	0.0492 (11)	0.0493 (11)	−0.0041 (8)	0.0062 (8)	0.0070 (9)

Geometric parameters (Å, º) top

O1—C7	1.267 (3)	C4—C5	1.520 (3)
O1—H1O	1.19 (4)	C4—H4	1.0
O2—C7	1.223 (3)	C5—H5A	0.98
O3—C8	1.270 (3)	C5—H5B	0.98
O3—H1O	1.20 (4)	C5—H5C	0.98
O4—C8	1.220 (3)	C6—H6A	0.98
N1—C4	1.501 (3)	C6—H6B	0.98
N1—C1	1.513 (2)	C6—H6C	0.98
N1—H1A	0.94 (3)	C7—C9	1.526 (3)
N1—H1B	0.95 (3)	C8—C10	1.517 (3)
C1—C3	1.506 (3)	C9—C14	1.387 (3)
C1—C2	1.510 (3)	C9—C10	1.415 (3)
C1—H1	1.0	C10—C11	1.405 (3)
C2—H2A	0.98	C11—C12	1.369 (3)
C2—H2B	0.98	C11—H11	0.95
C2—H2C	0.98	C12—C13	1.376 (3)
C3—H3A	0.98	C12—H12	0.95
C3—H3B	0.98	C13—C14	1.382 (3)
C3—H3C	0.98	C13—H13	0.95
C4—C6	1.510 (3)	C14—H14	0.95

C7—O1—H1O	112.8 (17)	H5A—C5—H5B	109.5
C8—O3—H1O	112.7 (17)	C4—C5—H5C	109.5
C4—N1—C1	118.04 (15)	H5A—C5—H5C	109.5
C4—N1—H1A	109.7 (15)	H5B—C5—H5C	109.5
C1—N1—H1A	107.7 (15)	C4—C6—H6A	109.5
C4—N1—H1B	108.6 (15)	C4—C6—H6B	109.5
C1—N1—H1B	107.0 (14)	H6A—C6—H6B	109.5
H1A—N1—H1B	105.0 (19)	C4—C6—H6C	109.5
C3—C1—C2	112.1 (2)	H6A—C6—H6C	109.5
C3—C1—N1	108.24 (17)	H6B—C6—H6C	109.5
C2—C1—N1	110.86 (19)	O2—C7—O1	121.79 (19)
C3—C1—H1	108.5	O2—C7—C9	118.10 (19)
C2—C1—H1	108.5	O1—C7—C9	120.10 (19)
N1—C1—H1	108.5	O4—C8—O3	121.6 (2)
C1—C2—H2A	109.5	O4—C8—C10	118.17 (18)
C1—C2—H2B	109.5	O3—C8—C10	120.20 (19)
H2A—C2—H2B	109.5	C14—C9—C10	118.24 (16)
C1—C2—H2C	109.5	C14—C9—C7	113.74 (17)
H2A—C2—H2C	109.5	C10—C9—C7	128.02 (17)
H2B—C2—H2C	109.5	C11—C10—C9	117.81 (17)
C1—C3—H3A	109.5	C11—C10—C8	113.78 (17)
C1—C3—H3B	109.5	C9—C10—C8	128.41 (16)
H3A—C3—H3B	109.5	C12—C11—C10	122.57 (19)
C1—C3—H3C	109.5	C12—C11—H11	118.7
H3A—C3—H3C	109.5	C10—C11—H11	118.7
H3B—C3—H3C	109.5	C11—C12—C13	119.40 (18)
N1—C4—C6	111.06 (18)	C11—C12—H12	120.3
N1—C4—C5	107.78 (17)	C13—C12—H12	120.3
C6—C4—C5	112.4 (2)	C12—C13—C14	119.42 (19)
N1—C4—H4	108.5	C12—C13—H13	120.3
C6—C4—H4	108.5	C14—C13—H13	120.3
C5—C4—H4	108.5	C13—C14—C9	122.54 (19)
C4—C5—H5A	109.5	C13—C14—H14	118.7
C4—C5—H5B	109.5	C9—C14—H14	118.7

C4—N1—C1—C3	−178.07 (18)	O4—C8—C10—C11	−8.3 (3)
C4—N1—C1—C2	58.6 (3)	O3—C8—C10—C11	171.3 (2)
C1—N1—C4—C6	61.3 (2)	O4—C8—C10—C9	172.6 (2)
C1—N1—C4—C5	−175.11 (19)	O3—C8—C10—C9	−7.7 (3)
O2—C7—C9—C14	10.5 (3)	C9—C10—C11—C12	1.5 (3)
O1—C7—C9—C14	−170.6 (2)	C8—C10—C11—C12	−177.7 (2)
O2—C7—C9—C10	−168.8 (2)	C10—C11—C12—C13	−0.4 (4)
O1—C7—C9—C10	10.1 (3)	C11—C12—C13—C14	−1.0 (4)
C14—C9—C10—C11	−1.1 (3)	C12—C13—C14—C9	1.3 (3)
C7—C9—C10—C11	178.11 (19)	C10—C9—C14—C13	−0.2 (3)
C14—C9—C10—C8	177.85 (19)	C7—C9—C14—C13	−179.6 (2)
C7—C9—C10—C8	−2.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···O3	1.19 (4)	1.20 (4)	2.385 (3)	173 (3)
N1—H1A···O4ⁱ	0.94 (3)	1.83 (3)	2.756 (3)	169 (2)
N1—H1B···O2	0.95 (3)	1.83 (3)	2.763 (2)	166 (2)
C3—H3C···O1	0.98	2.70	3.659 (3)	166
C3—H3A···O4ⁱ	0.98	2.69	3.392 (4)	129
C6—H6C···O2	0.98	2.68	3.408 (4)	132
C12—H12···O3ⁱⁱ	0.95	2.58	3.401 (2)	145
C13—H13···O1ⁱⁱ	0.95	2.61	3.449 (3)	148

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

Funding information

The authors acknowledge the Cheikh Anta Diop University, Dakar, Senegal, for their support and the US Department of Education via a Congressionally directed grant (grant No. P116Z100020) for the X-ray diffractometer.

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