Crystal structure of 4-(2-bromo­prop­ion­yl)-3-phenyl­sydnone

Grossie, D.; Harrison, L.; Turnbull, K.

doi:10.1107/S1600536814022260

organic compounds

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Volume 70| Part 11| November 2014| Pages o1165-o1166

doi:10.1107/S1600536814022260

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Crystal structure of 4-(2-bromopropionyl)-3-phenylsydnone

D. Grossie,^a ^* L. Harrison ^a and K. Turnbull ^a

^aWright State University, Chemistry, 3649 Colonel Glenn Hwy, Dayton, Ohio 45435, USA
^*Correspondence e-mail: david.grossie@wright.edu

Edited by S. Parkin, University of Kentucky, USA (Received 12 September 2014; accepted 8 October 2014; online 18 October 2014)

Sydnones are a class of mesoionic compounds containing a five-membered heterocyclic ring. In general, sydnone compounds are synthesized with an aromatic substutuent at the N³ position. This feature, adds to the stability of the heterocyclic ring. In the title compound {systematic name: 4-(2-bromopropanoyl)-3-phenyl-1,2,3λ⁵-oxadiazol-3-ylium-5-olate}, C₁₁H₉BrN₂O₃, the aromatic substitutent is an unsubstituted phenyl ring. The sydnone ring is almost planar, with a maximum deviation from the mean plane of 0.023 (1) Å, but is not coplanar with the phenyl ring, having a dihedral angle of 40.93 (8)°. The carbonyl side chain is twisted relative to the syndone ring by 15.8 (2)°. The molecules are packed in the unit cell as pairs related by an inversion center at (1, 0, 1/2). The pairs interact via π-stacking, with the distance separating the centroids being 3.824 (1) Å. The Br atom has two contacts, one to an N atom in a neighboring asymmetric unit with a distance of 3.346 (2) Å (the sum of the van der Waals radii is 3.40 Å) and a second to an H atom with a distance of 3.03 Å. The contact with the H atom is perpendicular (C—Br⋯H = 98.60°) to the C—Br bond, and that to the N atom is linear [C—Br⋯N = 169.10 (5)°] to the C—Br bond. The O atom of the sydnone ring is involved in two hydrogen bonds, one intramolecular with a donor–acceptor distance of 3.1486 (19) Å and a second that is intermolecular, with a phenyl H atom as the donor and has a donor–acceptor distance of 3.346 (2) Å.

Keywords: crystal structure; sydnone; mesoionic compounds; oxadiazolyliumolate; hydrogen bonding.

CCDC reference: 1028263

1. Related literature

For more information on the sydnone family of compounds, see: Ohta & Kato (1969 ). For synthesis and structural information, see: Hope & Thiessen (1969 ); Ollis & Ramsden (1976 ); Hodson & Turnbull (1985 ); Grossie & Turnbull (1992 ); Grossie et al. (2001 , 2007 ); Riddle et al. (2004a ,b ,c ). For further synthesis information, see: Balaguer et al. (2013 ). For halogen-bond information, see: Politzer et al. (2010 ).

2. Experimental

2.1. Crystal data

C₁₁H₉BrN₂O₃
M_r = 297.11
Triclinic, $[P \overline 1]$
a = 7.5388 (8) Å
b = 7.8094 (8) Å
c = 10.2470 (11) Å
α = 89.1333 (14)°
β = 77.2754 (14)°
γ = 72.6502 (13)°
V = 560.86 (10) Å³
Z = 2
Mo Kα radiation
μ = 3.66 mm⁻¹
T = 173 K
0.48 × 0.43 × 0.21 mm

2.2. Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2006 ) T_min = 0.586, T_max = 0.746
8816 measured reflections
3313 independent reflections
3091 reflections with I > 2σ(I)
R_int = 0.019

2.3. Refinement

R[F² > 2σ(F²)] = 0.025
wR(F²) = 0.068
S = 1.06
3313 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 0.83 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C35—H35⋯O41ⁱ	0.95	2.52	3.346 (2)	146
C42—H42⋯O5	1.00	2.43	3.1486 (19)	128
Symmetry code: (i) -x+2, -y, -z+1.

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

CCDC reference: 1028263

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814022260/pk2531sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814022260/pk2531Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814022260/pk2531Isup3.cml

checkCIF report

Comment top

The molecule contains one chiral center, C42, which in the asymmetric unit used in refinement has an S configuration. The sydnone (O1 - C5) and phenyl ring (C31 - C36) are planar with maximum deviation from the mean plane of 0.023 (1) and 0.006 (1) Å, respectively. The angle between the planes of the sydnone (O1 – C5) and phenyl ring (C31 – C36) is 40.93 (8)°. The molecule is packed in the unit cell with the phenyl ring of neighboring molecules lying parallel to one another, with a separation of 3.346 (2) Å. The molecules are related by an inversion center at (1, 0, 0.5), lying head-to-tail with the centroids of the parallel phenyl rings shifted by 1.851 (1) Å. Each pair of molecules is repeated with a separation between nearest rings of 3.317 (2) Å and an offset of 4.600 (2) Å. In addition, weak hydrogen- and halogen-bonding is observed around the bromine atom, a halogen-bond to N2 in a neighboring asymmetric unit with a distance of 3.346 (2) Å and a hydrogen-bond to H42 with a distance of 3.028Å. The hydrogen-bond with H42 has an angle at Br1 of 98.60° and the halogen bond has an angle of 169.10 (5)°. This behavior is characteristic of the "flattening" of halogen atoms in the direction of the C—Br bond as discussed by Politzer et al. (2010). The oxygen atom O5 of the sydnone ring is involved in two hydrogen bonds, one intramolecular to H42 with a D···A distance of 3.1486 (19) Å and a second that is intermolecular, using a phenyl hydrogen atom, H35, as the donor and has a D···A distance of 3.346 (2) Å. The packing of the molecules is shown in Fig. 2.

Synthesis top

3-Phenyl-4-(2-bromopropionyl)sydnone was prepared in 84% yield from 3-phenyl-4-propionyl)sydnone (itself synthesized in 63% yield from 3-phenylsydnone by Friedel-Crafts acylation with propionic anhydride, bismuth triflate and lithium perchlorate) by treatment with bromine (10 eq) in glacial acetic acid with a few drops of concentrated sulfuric acid at 40°C for 2 hours (Balaguer et al., 2013).

Refinement top

Crystal data, data collection and structure refinement details are summarized in the following tables. Refinement of the compound resulted in residual positive electron density (0.83 e Å^-3) in the vicinity the the Br atom. Hydrogen atom positions were calculated using geometric parameters and allowed to refined as a "riding" atom with a isotropic thermal factor equal to 1.5 Ueq of the attached atoms with sp³ hybridization and 1.2 Ueq of the attached atoms with sp² hybridization positions.

Related literature top

For more information on the sydnone family of compounds, see: Ohta & Kato (1969). For synthesis and structural information, see: Hope & Thiessen (1969); Ollis & Ramsden (1976); Hodson & Turnbull (1985); Grossie & Turnbull (1992); Grossie et al. (2001, 2007); Riddle et al. (2004a,b,c). For further synthesis information, see: Balaguer et al. (2013). For halogen-bond information, see: Politzer et al. (2010).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: APEX2 (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); 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).

Figures top

Fig. 1. The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.

Fig. 2. The packing diagram of the title compound, viewed down the a-axis.

4-(2-Bromopropanoyl)-3-phenyl-1,2,3λ⁵-oxadiazol-3-ylium-5-olate top

Crystal data top

C₁₁H₉BrN₂O₃	Z = 2
M_r = 297.11	F(000) = 296
Triclinic, P1	D_x = 1.759 Mg m⁻³
a = 7.5388 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.8094 (8) Å	Cell parameters from 4182 reflections
c = 10.2470 (11) Å	θ = 2.7–30.7°
α = 89.1333 (14)°	µ = 3.66 mm⁻¹
β = 77.2754 (14)°	T = 173 K
γ = 72.6502 (13)°	Block, clear colourless
V = 560.86 (10) Å³	0.48 × 0.43 × 0.21 mm

Data collection top

Bruker APEXII diffractometer	3091 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
ω scans	θ_max = 31.3°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2006)	h = −10→10
T_min = 0.586, T_max = 0.746	k = −11→11
8816 measured reflections	l = −14→14
3313 independent reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.025	H-atom parameters constrained
wR(F²) = 0.068	w = 1/[σ²(F_o²) + (0.047P)² + 0.071P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
3313 reflections	Δρ_max = 0.83 e Å⁻³
155 parameters	Δρ_min = −0.24 e Å⁻³
0 restraints

Crystal data top

C₁₁H₉BrN₂O₃	γ = 72.6502 (13)°
M_r = 297.11	V = 560.86 (10) Å³
Triclinic, P1	Z = 2
a = 7.5388 (8) Å	Mo Kα radiation
b = 7.8094 (8) Å	µ = 3.66 mm⁻¹
c = 10.2470 (11) Å	T = 173 K
α = 89.1333 (14)°	0.48 × 0.43 × 0.21 mm
β = 77.2754 (14)°

Data collection top

Bruker APEXII diffractometer	3313 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2006)	3091 reflections with I > 2σ(I)
T_min = 0.586, T_max = 0.746	R_int = 0.019
8816 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.025	0 restraints
wR(F²) = 0.068	H-atom parameters constrained
S = 1.06	Δρ_max = 0.83 e Å⁻³
3313 reflections	Δρ_min = −0.24 e Å⁻³
155 parameters

Special details top

Experimental. Absorption correction: SADABS-2008/1 (Bruker,2008) was used for absorption correction. wR2(int) was 0.1048 before and 0.0276 after correction. The Ratio of minimum to maximum transmission is 0.7846. The λ/2 correction factor is 0.0015.

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

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

Sydnone:O1—C5

0.7220 (5) x - 0.4771 (6) y + 0.5010 (7) z = 7.363 (6)

0.023 (1) O1* -0.016 (1) N2* 0.002 (1) N3* 0.012 (1) C4* -0.022 (2) C5*

Attached phenyl ring: C31–36

-0.1134 (6) x + 0.8146 (4) y - 0.5688 (5) z = -2.369 (5)

-0.004 (1) C31* -0.006 (1) C32* 0.004 (1) C33* -0.002 (1) C34* 0.005 (1) C35* -0.005 (1) C36

Angle to previous plane (with approximate e.s.d.) = 40.93 (8)

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

	x	y	z	U_iso*/U_eq
Br1	0.08657 (2)	0.41054 (2)	0.79958 (2)	0.02060 (6)
O5	0.37447 (17)	0.66470 (15)	0.94737 (11)	0.0212 (2)
O41	0.55129 (15)	0.11464 (14)	0.77220 (11)	0.0188 (2)
N3	0.66206 (17)	0.42537 (16)	0.66182 (12)	0.0141 (2)
O1	0.61412 (16)	0.67163 (14)	0.76973 (11)	0.0186 (2)
N2	0.71705 (18)	0.56946 (17)	0.65504 (13)	0.0174 (2)
C31	0.7431 (2)	0.30011 (19)	0.54603 (14)	0.0147 (2)
C4	0.52361 (19)	0.42322 (18)	0.77203 (14)	0.0143 (2)
C36	0.9357 (2)	0.26502 (19)	0.48800 (15)	0.0163 (3)
H36	1.0129	0.3173	0.5259	0.020*
C32	0.6253 (2)	0.2270 (2)	0.49368 (14)	0.0170 (3)
H32	0.4933	0.2548	0.5346	0.020*
C33	0.7057 (2)	0.1117 (2)	0.37938 (15)	0.0193 (3)
H33	0.6287	0.0583	0.3422	0.023*
C42	0.2688 (2)	0.30934 (19)	0.91455 (14)	0.0153 (3)
H42	0.2597	0.4037	0.9827	0.018*
C41	0.4596 (2)	0.26752 (19)	0.81517 (14)	0.0143 (2)
C5	0.4824 (2)	0.58994 (19)	0.84533 (15)	0.0164 (3)
C34	0.8990 (2)	0.0748 (2)	0.31958 (15)	0.0202 (3)
H34	0.9531	−0.0035	0.2415	0.024*
C35	1.0130 (2)	0.1516 (2)	0.37324 (15)	0.0186 (3)
H35	1.1444	0.1264	0.3313	0.022*
C43	0.2287 (2)	0.1487 (2)	0.98465 (15)	0.0206 (3)
H43A	0.0956	0.1825	1.0349	0.031*
H43B	0.3133	0.1080	1.0465	0.031*
H43C	0.2511	0.0514	0.9180	0.031*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01601 (8)	0.02299 (9)	0.02065 (9)	−0.00160 (6)	−0.00565 (5)	0.00083 (6)
O5	0.0253 (6)	0.0159 (5)	0.0184 (5)	−0.0025 (4)	−0.0019 (4)	−0.0031 (4)
O41	0.0191 (5)	0.0133 (5)	0.0201 (5)	−0.0018 (4)	−0.0003 (4)	−0.0004 (4)
N3	0.0130 (5)	0.0146 (5)	0.0152 (5)	−0.0042 (4)	−0.0042 (4)	0.0009 (4)
O1	0.0204 (5)	0.0160 (5)	0.0201 (5)	−0.0069 (4)	−0.0040 (4)	−0.0013 (4)
N2	0.0176 (6)	0.0168 (5)	0.0188 (6)	−0.0068 (4)	−0.0039 (4)	0.0004 (4)
C31	0.0161 (6)	0.0142 (6)	0.0131 (6)	−0.0038 (5)	−0.0032 (5)	0.0015 (5)
C4	0.0142 (6)	0.0142 (6)	0.0134 (6)	−0.0038 (5)	−0.0015 (5)	0.0003 (5)
C36	0.0162 (6)	0.0163 (6)	0.0167 (6)	−0.0060 (5)	−0.0033 (5)	0.0030 (5)
C32	0.0163 (6)	0.0189 (6)	0.0165 (6)	−0.0053 (5)	−0.0051 (5)	0.0021 (5)
C33	0.0241 (7)	0.0191 (7)	0.0172 (6)	−0.0076 (5)	−0.0083 (5)	0.0012 (5)
C42	0.0159 (6)	0.0158 (6)	0.0131 (6)	−0.0035 (5)	−0.0025 (5)	−0.0001 (5)
C41	0.0159 (6)	0.0144 (6)	0.0124 (6)	−0.0038 (5)	−0.0039 (5)	0.0013 (5)
C5	0.0186 (6)	0.0144 (6)	0.0168 (6)	−0.0043 (5)	−0.0059 (5)	0.0018 (5)
C34	0.0263 (7)	0.0170 (6)	0.0153 (6)	−0.0054 (5)	−0.0021 (5)	0.0001 (5)
C35	0.0186 (6)	0.0170 (6)	0.0175 (6)	−0.0043 (5)	−0.0002 (5)	0.0025 (5)
C43	0.0231 (7)	0.0206 (7)	0.0168 (7)	−0.0078 (6)	−0.0003 (5)	0.0024 (5)

Geometric parameters (Å, º) top

Br1—C42	1.9842 (14)	C32—H32	0.9500
O5—C5	1.2070 (18)	C32—C33	1.394 (2)
O41—C41	1.2192 (17)	C33—H33	0.9500
N3—N2	1.3062 (17)	C33—C34	1.394 (2)
N3—C31	1.4483 (18)	C42—H42	1.0000
N3—C4	1.3622 (18)	C42—C41	1.5158 (19)
O1—N2	1.3701 (16)	C42—C43	1.512 (2)
O1—C5	1.4200 (18)	C34—H34	0.9500
C31—C36	1.3873 (19)	C34—C35	1.388 (2)
C31—C32	1.3872 (19)	C35—H35	0.9500
C4—C41	1.4649 (19)	C43—H43A	0.9800
C4—C5	1.4289 (19)	C43—H43B	0.9800
C36—H36	0.9500	C43—H43C	0.9800
C36—C35	1.389 (2)

N2—N3—C31	115.61 (12)	C41—C42—H42	109.5
N2—N3—C4	114.72 (12)	C43—C42—Br1	111.26 (10)
C4—N3—C31	129.37 (12)	C43—C42—H42	109.5
N2—O1—C5	110.83 (10)	C43—C42—C41	114.62 (12)
N3—N2—O1	105.26 (11)	O41—C41—C4	122.48 (13)
C36—C31—N3	117.95 (13)	O41—C41—C42	121.98 (13)
C32—C31—N3	119.37 (12)	C4—C41—C42	115.52 (12)
C32—C31—C36	122.61 (13)	O5—C5—O1	120.00 (13)
N3—C4—C41	125.59 (12)	O5—C5—C4	136.41 (14)
N3—C4—C5	105.46 (12)	O1—C5—C4	103.57 (12)
C5—C4—C41	128.09 (13)	C33—C34—H34	119.7
C31—C36—H36	120.8	C35—C34—C33	120.51 (14)
C31—C36—C35	118.43 (14)	C35—C34—H34	119.7
C35—C36—H36	120.8	C36—C35—H35	119.9
C31—C32—H32	120.9	C34—C35—C36	120.20 (13)
C31—C32—C33	118.20 (13)	C34—C35—H35	119.9
C33—C32—H32	120.9	C42—C43—H43A	109.5
C32—C33—H33	120.0	C42—C43—H43B	109.5
C32—C33—C34	120.04 (14)	C42—C43—H43C	109.5
C34—C33—H33	120.0	H43A—C43—H43B	109.5
Br1—C42—H42	109.5	H43A—C43—H43C	109.5
C41—C42—Br1	102.16 (9)	H43B—C43—H43C	109.5

Br1—C42—C41—O41	−103.92 (14)	C31—C36—C35—C34	−0.5 (2)
Br1—C42—C41—C4	74.62 (12)	C31—C32—C33—C34	−1.0 (2)
N3—C31—C36—C35	−177.06 (13)	C4—N3—N2—O1	1.77 (16)
N3—C31—C32—C33	177.78 (13)	C4—N3—C31—C36	−144.40 (15)
N3—C4—C41—O41	15.8 (2)	C4—N3—C31—C32	38.7 (2)
N3—C4—C41—C42	−162.76 (13)	C36—C31—C32—C33	1.0 (2)
N3—C4—C5—O5	178.85 (18)	C32—C31—C36—C35	−0.2 (2)
N3—C4—C5—O1	−2.85 (15)	C32—C33—C34—C35	0.3 (2)
N2—N3—C31—C36	42.21 (18)	C33—C34—C35—C36	0.5 (2)
N2—N3—C31—C32	−134.71 (14)	C41—C4—C5—O5	−11.4 (3)
N2—N3—C4—C41	−169.29 (13)	C41—C4—C5—O1	166.87 (13)
N2—N3—C4—C5	0.77 (17)	C5—O1—N2—N3	−3.68 (15)
N2—O1—C5—O5	−177.26 (13)	C5—C4—C41—O41	−152.03 (15)
N2—O1—C5—C4	4.09 (15)	C5—C4—C41—C42	29.4 (2)
C31—N3—N2—O1	176.15 (11)	C43—C42—C41—O41	16.5 (2)
C31—N3—C4—C41	17.3 (2)	C43—C42—C41—C4	−164.94 (13)
C31—N3—C4—C5	−172.67 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C35—H35···O41ⁱ	0.95	2.52	3.346 (2)	146
C42—H42···O5	1.00	2.43	3.1486 (19)	128

Symmetry code: (i) −x+2, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C35—H35···O41ⁱ	0.95	2.52	3.346 (2)	146
C42—H42···O5	1.00	2.43	3.1486 (19)	128

Symmetry code: (i) −x+2, −y, −z+1.

Halogen-bond Geometry (Å, °) top

D-Br···A	D-Br	Br···A	D···A	D-Br···A
C42-Br1···N2ⁱ	1.9842 (15)	3.3458 (14)	5.307 (2)	169.10 (5)
C42-Br1···H42ⁱⁱ	1.9842 (15)	3.03	3.860	98.60

(i) 1-x,y,z (ii) -x,1-y,2-z

Acknowledgements

The authors would like to acknowledge the diffractometer time granted by A. Hunter, Youngstown State University.

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Volume 70| Part 11| November 2014| Pages o1165-o1166

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