Tetra­aqua­bis­(2,3-di­hydro-1,4-benzodioxine-2-carboxyl­ato)calcium(II)

Camargo-Cortés, E.B.; Acosta, M.; Martínez, J.C.; Pineda, L.W.

doi:10.1107/S2414314620010925

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 5| Part 8| August 2020| x201092

https://doi.org/10.1107/S2414314620010925

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Tetraaquabis(2,3-dihydro-1,4-benzodioxine-2-carboxylato)calcium(II)

Esmit B. Camargo-Cortés,^a ^* Mirna Acosta,^a Juan C. Martínez ^a and Leslie W. Pineda ^b,^c

^aCentro Especializado en Investigaciones en Química Inorgánica (CEIQUI), Escuela de Química, Universidad Autónoma de Chiriquí, David, Panama, ^bCentro de Electroquímica y Energía Química (CELEQ), Universidad de Costa Rica, 11501-2060. San José, Costa Rica, and ^cEscuela de Química, Universidad de Costa Rica, 11501-2060, San José, Costa Rica
^*Correspondence e-mail: esmit.camargo@unachi.ac.pa

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 27 July 2020; accepted 9 August 2020; online 14 August 2020)

The acid–base reaction of 1,4-benzodioxane 2-carboxylic acid with calcium carbonate furnished the centrosymmetric title compound, [Ca(C₉H₇O₄)₂(H₂O)₄], in which the metal ion is octahedrally coordinated by two monodentate 1,4-benzodioxane 2-carboxylate ligands and four water molecules. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the molecules into a three-dimensional network.

Keywords: crystal structure; 1,4-benzodioxane; calcium atom; carboxylate groups; hydrogen bonding.

CCDC reference: 1970573

Structure description

1,4-Benzodioxanes are components of some therapeutic agents used in cardiovascular treatments, acting as α- and β-adrenergic antagonists (Nelson et al., 1977 , 1979 ; Pigini et al., 1988 ). For the latter application, the enantiopure derivatives of chiral 2-substituted 1,4-benzodioxanes lend affinity and selectivity, mainly those derived from 1,4-benzodioxane 2-carboxylic acid (Ennis & Old, 1992 ; Antus et al., 1993 ; Khouili et al., 1999 ; Jasinski et al., 2009 ). Naturally ocurring compounds with a similar structure to these heterocyclic scaffolds are known as 1,4-benzodioxane lignans, which also exhibit a wide array of biological activities (e.g., anticancer, antioxidant; Pilkington & Barker, 2015 ).

In this work, we report the synthesis and the structure of the coordination properties of 1,4-benzodioxane 2-carboxylic acid toward calcium carbonate to afford the title compound Ca(C₉H₇O₄)₂(H₂O)₄.

The crystal structure of the title compound has monoclinic symmetry with half a molecule in the asymmetric unit, the other half being generated by a crystallographic inversion center. The calcium ion is bonded to four aqua ligands and two 1,4-benzodioxane 2-carboxylate ligands, whose carboxylate groups link to the central atom in monodentate mode (Fig. 1). The Ca1—O1, Ca1—O5, and Ca1—O6 bond lengths are 2.304 (2), 2.358 (2) and 2.317 (2) Å, respectively. The dioxane ring adopts a half-chair conformation with the pendant carboxylate group in an axial orientation. In the arbitrarily chosen asymmetric unit, C2 has an R configuration but crystal symmetry generates a racemic mixture.

Figure 1
The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. Unlabeled atoms are generated by the symmetry operation 1 − x, 1 − y, 2 − z.

In the crystal, O—H⋯O hydrogen bonds link the molecules into (010) sheets with the acceptor O atoms being parts of carboxylate groups (O1 and O2) and the dioxane ring (O4) and the packing is consolidated by weak C—H⋯O interactions (Fig. 2, Table 1).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5A⋯O1ⁱ	0.84 (2)	1.96 (2)	2.800 (3)	178 (4)
O5—H5B⋯O4ⁱⁱ	0.84 (3)	2.07 (3)	2.828 (3)	149 (4)
O6—H6A⋯O2ⁱⁱⁱ	0.83 (3)	1.93 (2)	2.707 (3)	155 (3)
O6—H6B⋯O2ⁱ	0.84 (3)	1.88 (4)	2.715 (3)	176 (3)
C2—H2⋯O2ⁱ	1.00	2.53	3.379 (4)	143
C6—H6⋯O3^iv	0.95	2.54	3.357 (4)	145
Symmetry codes: (i) x-1, y, z; (ii) x, y, z+1; (iii) -x+1, -y+1, -z+1; (iv) $[x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Figure 2
Packing of the molecules of the title compound. O—H⋯O and C—H⋯O hydrogen bonds are shown as green dashed lines.

Synthesis and crystallization

In a 100 mL two-necked flask, anhydrous CaCO₃ (0.0100 g, 0.100 mmol) was dissolved in deionized water (20 mL) by heating to 338 K, and a solution of 1,4-benzodioxane-2-carboxylic acid (0.0560 g, 0.200 mmol) dissolved in distilled water (10 mL) was added dropwise at 353 K. The reaction mixture was refluxed for 2 h and then concentrated under vacuum to 10 mL. The precipitate obtained upon cooling overnight was filtered off and washed with cold distilled water. Colorless crystals suitable for X-ray analysis were grown from a warm water–methanol mixed solvent mixture (1:1) at room temperature. Yield: 0.0362 g (55%), m.p. 501–505 K. FTIR data (KBr, cm⁻¹): 3600 and 3000 (br, m); 3568 (m); 1330 (m); 879 (m); 833 (s); 767 (s); 752 (s); 654 (m); 569 (m); 545 (w); 476 (m). ¹H NMR (400 MHz, mix 1:1 D₂O: CD₄O, 298 K): δ 6.87–6.99 (s, 4H), 4.82 (dd, 1H), 4.35 p.p.m. (qd, 2H). ¹³C NMR (400 MHz, 1:1 mix D₂O: CD₄O, 298 K): δ 176, 143, 142, 123, 122, 117, 115, 73.5, 66 p.p.m. The ¹H NMR and ¹³C NMR spectra for the title compound are included in the supporting information.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	[Ca(C₉H₇O₄)₂(H₂O)₄]
M_r	470.44
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	5.3477 (4), 26.6084 (18), 7.7367 (5)
β (°)	106.715 (2)
V (Å³)	1054.37 (13)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.36
Crystal size (mm)	0.35 × 0.25 × 0.15

Data collection
Diffractometer	Bruker D8 Venture
Absorption correction	Multi-scan (SADABS; Bruker, 2015 )
T_min, T_max	0.661, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	32373, 2384, 2242
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.647

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.133, 1.39
No. of reflections	2384
No. of parameters	158
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.43
Computer programs: APEX3 and SAINT (Bruker, 2015), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), Mercury (Macrae et al., 2020 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1970573

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314620010925/hb4355sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620010925/hb4355Isup2.hkl

1H and 13C NMR spectra of the title compound. DOI: https://doi.org/10.1107/S2414314620010925/hb4355sup3.pdf

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2015); cell refinement: SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2020); software used to prepare material for publication: publCIF (Westrip, 2010).

Tetraaquabis(2,3-dihydro-1,4-benzodioxine-2-carboxylato)calcium(II) top

Crystal data top

[Ca(C₉H₇O₄)₂(H₂O)₄]	F(000) = 492
M_r = 470.44	D_x = 1.482 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 5.3477 (4) Å	Cell parameters from 9843 reflections
b = 26.6084 (18) Å	θ = 2.9–27.4°
c = 7.7367 (5) Å	µ = 0.36 mm⁻¹
β = 106.715 (2)°	T = 100 K
V = 1054.37 (13) Å³	Block, clear light white
Z = 2	0.35 × 0.25 × 0.15 mm

Data collection top

Bruker D8 Venture diffractometer	2384 independent reflections
Mirrors monochromator	2242 reflections with I > 2σ(I)
Detector resolution: 10.4167 pixels mm^-1	R_int = 0.036
ω scans	θ_max = 27.4°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2015)	h = −6→6
T_min = 0.661, T_max = 0.746	k = −34→34
32373 measured reflections	l = −10→8

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)] = 0.057	Hydrogen site location: mixed
wR(F²) = 0.133	H atoms treated by a mixture of independent and constrained refinement
S = 1.39	w = 1/[σ²(F_o²) + 3.3804P] where P = (F_o² + 2F_c²)/3
2384 reflections	(Δ/σ)_max < 0.001
158 parameters	Δρ_max = 0.42 e Å⁻³
6 restraints	Δρ_min = −0.43 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.

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

	x	y	z	U_iso*/U_eq
Ca1	0.5	0.5	1.0	0.0115 (2)
O1	0.6722 (4)	0.55435 (8)	0.8323 (3)	0.0144 (4)
O2	0.8347 (4)	0.54948 (9)	0.5982 (3)	0.0164 (5)
O3	0.5527 (5)	0.66992 (9)	0.6702 (3)	0.0199 (5)
O4	0.4402 (4)	0.60021 (8)	0.3776 (3)	0.0144 (4)
O5	0.2000 (4)	0.56223 (9)	1.0277 (3)	0.0167 (5)
H5A	0.041 (3)	0.5599 (16)	0.972 (4)	0.030 (12)*
H5B	0.210 (7)	0.5750 (15)	1.129 (3)	0.033 (12)*
O6	0.1782 (4)	0.47510 (9)	0.7438 (3)	0.0158 (5)
H6A	0.208 (8)	0.4613 (13)	0.655 (3)	0.028 (12)*
H6B	0.070 (7)	0.4981 (12)	0.703 (5)	0.043 (14)*
C1	0.6624 (6)	0.56196 (11)	0.6687 (4)	0.0116 (6)
C2	0.4144 (6)	0.58769 (12)	0.5516 (4)	0.0121 (6)
H2	0.2671	0.5632	0.5335	0.015*
C3	0.3443 (6)	0.63398 (12)	0.6413 (5)	0.0171 (6)
H3A	0.1807	0.6488	0.5636	0.021*
H3B	0.316	0.6247	0.7582	0.021*
C4	0.6346 (6)	0.67786 (12)	0.5198 (4)	0.0160 (6)
C5	0.7822 (7)	0.72053 (13)	0.5151 (5)	0.0226 (7)
H5	0.8188	0.7437	0.6124	0.027*
C6	0.8762 (7)	0.72926 (13)	0.3682 (5)	0.0261 (8)
H6	0.9784	0.7583	0.3656	0.031*
C7	0.8210 (7)	0.69567 (14)	0.2255 (5)	0.0251 (8)
H7	0.8838	0.702	0.1246	0.03*
C8	0.6745 (6)	0.65272 (13)	0.2289 (4)	0.0191 (7)
H8	0.6373	0.6297	0.1311	0.023*
C9	0.5828 (6)	0.64388 (11)	0.3781 (4)	0.0129 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ca1	0.0075 (4)	0.0198 (4)	0.0070 (4)	0.0002 (3)	0.0018 (3)	0.0016 (3)
O1	0.0118 (10)	0.0243 (12)	0.0078 (10)	0.0001 (8)	0.0037 (8)	0.0026 (8)
O2	0.0128 (10)	0.0270 (12)	0.0100 (10)	0.0058 (9)	0.0041 (8)	0.0011 (9)
O3	0.0215 (12)	0.0206 (12)	0.0194 (12)	−0.0010 (9)	0.0089 (9)	−0.0046 (9)
O4	0.0146 (10)	0.0181 (11)	0.0091 (10)	−0.0028 (8)	0.0013 (8)	0.0012 (8)
O5	0.0087 (10)	0.0279 (12)	0.0125 (11)	0.0006 (9)	0.0015 (8)	−0.0042 (9)
O6	0.0144 (11)	0.0227 (12)	0.0095 (10)	0.0042 (9)	0.0022 (8)	−0.0015 (9)
C1	0.0105 (13)	0.0133 (13)	0.0107 (13)	−0.0024 (10)	0.0025 (11)	−0.0008 (10)
C2	0.0080 (13)	0.0196 (15)	0.0090 (13)	−0.0004 (11)	0.0027 (10)	0.0020 (11)
C3	0.0113 (14)	0.0227 (16)	0.0209 (16)	0.0027 (12)	0.0103 (12)	0.0029 (13)
C4	0.0125 (14)	0.0164 (15)	0.0179 (15)	0.0035 (11)	0.0023 (12)	0.0026 (12)
C5	0.0173 (16)	0.0154 (15)	0.0330 (19)	0.0005 (12)	0.0039 (14)	0.0005 (14)
C6	0.0172 (17)	0.0210 (17)	0.038 (2)	−0.0025 (13)	0.0051 (15)	0.0121 (15)
C7	0.0187 (16)	0.0316 (19)	0.0244 (18)	0.0005 (14)	0.0053 (14)	0.0144 (15)
C8	0.0182 (16)	0.0249 (17)	0.0124 (15)	0.0016 (13)	0.0016 (12)	0.0059 (12)
C9	0.0077 (13)	0.0177 (15)	0.0141 (14)	0.0025 (11)	0.0041 (11)	0.0042 (11)

Geometric parameters (Å, º) top

Ca1—O1ⁱ	2.304 (2)	O6—H6B	0.839 (10)
Ca1—O1	2.304 (2)	C1—C2	1.535 (4)
Ca1—O6ⁱ	2.317 (2)	C2—C3	1.513 (4)
Ca1—O6	2.317 (2)	C2—H2	1.0
Ca1—O5ⁱ	2.358 (2)	C3—H3A	0.99
Ca1—O5	2.358 (2)	C3—H3B	0.99
Ca1—H6B	2.74 (4)	C4—C9	1.386 (4)
O1—C1	1.268 (4)	C4—C5	1.389 (5)
O2—C1	1.243 (4)	C5—C6	1.388 (5)
O3—C4	1.372 (4)	C5—H5	0.95
O3—C3	1.437 (4)	C6—C7	1.385 (6)
O4—C9	1.389 (4)	C6—H6	0.95
O4—C2	1.432 (3)	C7—C8	1.390 (5)
O5—H5A	0.838 (10)	C7—H7	0.95
O5—H5B	0.838 (10)	C8—C9	1.397 (4)
O6—H6A	0.837 (10)	C8—H8	0.95

O1ⁱ—Ca1—O1	180.0	O1—C1—C2	116.1 (3)
O1ⁱ—Ca1—O6ⁱ	90.95 (8)	O4—C2—C3	110.2 (2)
O1—Ca1—O6ⁱ	89.05 (8)	O4—C2—C1	111.0 (2)
O1ⁱ—Ca1—O6	89.05 (8)	C3—C2—C1	112.3 (2)
O1—Ca1—O6	90.95 (8)	O4—C2—H2	107.7
O6ⁱ—Ca1—O6	180.00 (10)	C3—C2—H2	107.7
O1ⁱ—Ca1—O5ⁱ	90.17 (8)	C1—C2—H2	107.7
O1—Ca1—O5ⁱ	89.83 (8)	O3—C3—C2	109.3 (2)
O6ⁱ—Ca1—O5ⁱ	85.49 (8)	O3—C3—H3A	109.8
O6—Ca1—O5ⁱ	94.51 (8)	C2—C3—H3A	109.8
O1ⁱ—Ca1—O5	89.83 (8)	O3—C3—H3B	109.8
O1—Ca1—O5	90.17 (8)	C2—C3—H3B	109.8
O6ⁱ—Ca1—O5	94.51 (8)	H3A—C3—H3B	108.3
O6—Ca1—O5	85.49 (8)	O3—C4—C9	122.0 (3)
O5ⁱ—Ca1—O5	180.0	O3—C4—C5	118.1 (3)
O1ⁱ—Ca1—H6B	94.9 (10)	C9—C4—C5	119.9 (3)
O1—Ca1—H6B	85.1 (9)	C6—C5—C4	120.0 (3)
O6ⁱ—Ca1—H6B	163.5 (6)	C6—C5—H5	120.0
O6—Ca1—H6B	16.5 (6)	C4—C5—H5	120.0
O5ⁱ—Ca1—H6B	109.8 (6)	C7—C6—C5	120.0 (3)
O5—Ca1—H6B	70.2 (6)	C7—C6—H6	120.0
C1—O1—Ca1	138.9 (2)	C5—C6—H6	120.0
C4—O3—C3	113.1 (2)	C6—C7—C8	120.5 (3)
C9—O4—C2	113.2 (2)	C6—C7—H7	119.7
Ca1—O5—H5A	121 (3)	C8—C7—H7	119.7
Ca1—O5—H5B	120 (3)	C7—C8—C9	119.2 (3)
H5A—O5—H5B	107 (2)	C7—C8—H8	120.4
Ca1—O6—H6A	124 (3)	C9—C8—H8	120.4
Ca1—O6—H6B	112 (3)	C4—C9—O4	122.1 (3)
H6A—O6—H6B	106 (2)	C4—C9—C8	120.4 (3)
O2—C1—O1	124.9 (3)	O4—C9—C8	117.5 (3)
O2—C1—C2	118.9 (3)

Ca1—O1—C1—O2	−102.2 (4)	O3—C4—C5—C6	178.0 (3)
Ca1—O1—C1—C2	76.5 (4)	C9—C4—C5—C6	0.4 (5)
C9—O4—C2—C3	45.0 (3)	C4—C5—C6—C7	0.6 (5)
C9—O4—C2—C1	−79.9 (3)	C5—C6—C7—C8	−0.8 (5)
O2—C1—C2—O4	−8.8 (4)	C6—C7—C8—C9	0.2 (5)
O1—C1—C2—O4	172.4 (2)	O3—C4—C9—O4	1.4 (5)
O2—C1—C2—C3	−132.6 (3)	C5—C4—C9—O4	178.9 (3)
O1—C1—C2—C3	48.5 (4)	O3—C4—C9—C8	−178.6 (3)
C4—O3—C3—C2	48.5 (3)	C5—C4—C9—C8	−1.1 (5)
O4—C2—C3—O3	−63.0 (3)	C2—O4—C9—C4	−15.5 (4)
C1—C2—C3—O3	61.3 (3)	C2—O4—C9—C8	164.4 (3)
C3—O3—C4—C9	−19.4 (4)	C7—C8—C9—C4	0.8 (5)
C3—O3—C4—C5	163.1 (3)	C7—C8—C9—O4	−179.1 (3)

Symmetry code: (i) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O1ⁱⁱ	0.84 (2)	1.96 (2)	2.800 (3)	178 (4)
O5—H5B···O4ⁱⁱⁱ	0.84 (3)	2.07 (3)	2.828 (3)	149 (4)
O6—H6A···O2^iv	0.83 (3)	1.93 (2)	2.707 (3)	155 (3)
O6—H6B···O2ⁱⁱ	0.84 (3)	1.88 (4)	2.715 (3)	176 (3)
C2—H2···O2ⁱⁱ	1.00	2.53	3.379 (4)	143
C6—H6···O3^v	0.95	2.54	3.357 (4)	145

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

Acknowledgements

Rectoría and Vicerrectoría de Investigación, Universidad de Costa Rica are acknowledged for funding the purchase of a D8 Venture SC XRD. CELEQ is thanked for supporting liquid nitrogen for the X-ray measurements.

Funding information

Funding for this research was provided by: Centro de Electroquímica y Energía Química (CELEQ), Universidad de Costa Rica; Escuela de Química, Universidad de Costa Rica; Vicerrectoría de Investigación y Posgrado, Universidad Autónoma de Chiriquí, Panamá (grant No. 1.87-205-100-2016-23-i01).

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