4-Phenyl-1-[(1R,4R)-1,7,7-trimethyl-2-oxobi­cyclo[2.2.1]heptan-3-yl­idene]hydrazinecarbo­thio­amide

Oliveira, G.P. de; Bresolin, L.; Nogueira, V.S.; Zambiazi, P.J.; Oliveira, A.B. de

doi:10.1107/S2414314616017302

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 1| Part 11| November 2016| x161730

https://doi.org/10.1107/S2414314616017302

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4-Phenyl-1-[(1R,4R)-1,7,7-trimethyl-2-oxobicyclo[2.2.1]heptan-3-ylidene]hydrazinecarbothioamide

Gabriela Porto de Oliveira,^a Leandro Bresolin,^a ^* Vanessa Senna Nogueira,^a Priscila Jussiane Zambiazi ^b and Adriano Bof de Oliveira ^c

^aEscola de Química e Alimentos, Universidade Federal do Rio Grande, Av. Itália km 08, Campus Carreiros, 96203-900 Rio Grande-RS, Brazil, ^bDepartamento de Química, Universidade Federal de Santa Maria, Av. Roraima s/n, Campus Universitário, 97105-900 Santa Maria-RS, Brazil, and ^cDepartamento de Química, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, Campus Universitário, 49100-000 São Cristóvão-SE, Brazil
^*Correspondence e-mail: leandro_bresolin@yahoo.com.br

Edited by I. Brito, University of Antofagasta, Chile (Received 12 October 2016; accepted 27 October 2016; online 1 November 2016)

In the title compound, C₁₇H₂₁N₃OS [common nomenclature: (R)-camphor 4-phenylthiosemicarbazone], the N—N—C—(S)—N fragment deviates slightly from planarity, with a maximum deviation of 0.0259 (12) Å for the hydrazinic N atom, and makes an angle of 29.55 (0)° with the aromatic ring. The molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond and a short N—H⋯N interaction with graph-set motifs S(6) and S(5), respectively. In the crystal, the centrosymmetric arrangement of the molecules resembles a herringbone packing motif along [001]. As a result of the steric effects of the camphor entity, an apolar organic periphery and the intramolecular nature of the hydrogen bonds, neither strong nor relevant intermolecular interactions are observed.

Keywords: crystal structure; camphor derivative; herringbone packing motif; chiral thiosemicarbazone derivative.

CCDC reference: 1512001

Structure description

As part of our study of the structural chemistry of camphor-thiosemicarbazone derivatives (Nogueira et al. 2015 ), we report herein the crystal structure of R-camphor-4-phenylthiosemicarbazone (Fig. 1). The molecule is not planar due to the camphor entity. The N1—N2—C11(=S1)—N3 fragment is almost planar with the maximum deviation being 0.0259 (12) Å for N2, and makes a dihedral angle of 29.55 (8)° with the aromatic ring. Two intramolecular interactions N3—H22⋯N1 with graph-set motif S(5), and N22–H21⋯O1 with graph-set motif S(6) rings] are the outstanding features of the structure (Fig. 1 and Table 1). The R-camphor entity contributes two chiral centres to the molecule at C3 and C6, but since the space group is centrosymmetric no effect on cell anisotropy should be expected due to molecular chirality.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H21⋯O1	0.88	2.08	2.769 (2)	135
N3—H22⋯N1	0.88	2.16	2.607 (2)	111

Figure 1
The molecular structure of the title compound, showing the labelling and displacement ellipsoids drawn at the 40% probability level.

In the crystal, the molecules show neither strong nor relevant intermolecular interactions of any kind (e.g. no intermolecular hydrogen-bonding or π–π interactions), probably due to the steric effect of the camphor entity with a substantial apolar organic periphery for such a small molecule and to the intramolecular nature of the hydrogen bonding. The structure shows a centrosymmetric herringbone packing motif, Fig. 2.

Figure 2
Part of the crystal structure of the title compound, viewed along [100]. The centrosymmetric arrangement of the molecules resembles a herringbone packing motif.

Synthesis and crystallization

Starting materials were commercially available and were used without further purification. R-camphor was oxidized with SeO₂ to the respective 1,2-diketone (Młochowski & Wójtowicz-Młochowska, 2015 ). The synthesis of the R-camphor-4-phenylthiosemicarbazone derivative was adapted from a procedure reported previously (Freund & Schander, 1902 ). The glacial acetic acid-catalysed reaction of the 1,2-diketone (3 mmol) and 4-phenylthiosemicarbazide (3 mmol) in ethanol (50 ml) was stirred and refluxed for 6 h. Single crystals suitable for X-ray diffraction were obtained from an ethanol solution by solvent evaporation. The assignment of the correct absolute configuration was assured by the use of enantiopure reagent. The C3 and C6 chiral centres of the R-camphor remain unchanged during the synthesis.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₇H₂₁N₃OS
M_r	315.43
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	100
a, b, c (Å)	11.7947 (9), 14.2221 (11), 18.7864 (15)
V (Å³)	3151.3 (4)
Z	8
Radiation type	Mo Kα
μ (mm⁻¹)	0.21
Crystal size (mm)	0.22 × 0.20 × 0.13

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2012 )
T_min, T_max	0.956, 0.972
No. of measured, independent and observed [I > 2σ(I)] reflections	94152, 3933, 2879
R_int	0.105
(sin θ/λ)_max (Å⁻¹)	0.669

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.108, 1.08
No. of reflections	3933
No. of parameters	202
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.27
Computer programs: APEX2 and SAINT (Bruker, 2012), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), DIAMOND (Brandenburg, 2006 ), publCIF (Westrip, 2010 ) and enCIFer (Allen et al., 2004 ).

Structural data

CCDC reference: 1512001

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314616017302/bx4004sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616017302/bx4004Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010) and enCIFer (Allen et al., 2004).

4-Phenyl-1-[(1R,4R)-1,7,7-trimethyl-2-oxobicyclo[2.2.1]heptan-3-ylidene]hydrazinecarbothioamide top

Crystal data top

C₁₇H₂₁N₃OS	F(000) = 1344
M_r = 315.43	D_x = 1.330 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 9840 reflections
a = 11.7947 (9) Å	θ = 2.5–27.4°
b = 14.2221 (11) Å	µ = 0.21 mm⁻¹
c = 18.7864 (15) Å	T = 100 K
V = 3151.3 (4) Å³	Block, yellow
Z = 8	0.22 × 0.20 × 0.13 mm

Data collection top

Bruker APEXII CCD diffractometer	3933 independent reflections
Radiation source: fine-focus sealed tube, Bruker APEXII	2879 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.105
φ and ω scans	θ_max = 28.4°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2012)	h = −15→13
T_min = 0.956, T_max = 0.972	k = −19→18
94152 measured reflections	l = −25→25

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)] = 0.051	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.108	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.031P)² + 3.2431P] where P = (F_o² + 2F_c²)/3
3933 reflections	(Δ/σ)_max < 0.001
202 parameters	Δρ_max = 0.37 e Å⁻³
0 restraints	Δρ_min = −0.27 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. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
C1	0.71911 (16)	−0.04008 (13)	0.44422 (10)	0.0189 (4)
C2	0.75320 (16)	−0.14112 (13)	0.43709 (10)	0.0186 (4)
C3	0.67901 (17)	−0.18022 (14)	0.37840 (10)	0.0218 (4)
C4	0.72486 (17)	−0.13055 (15)	0.30938 (10)	0.0245 (4)
H1	0.8085	−0.1355	0.3066	0.029*
H2	0.6915	−0.1592	0.2662	0.029*
C5	0.68791 (17)	−0.02744 (15)	0.31681 (10)	0.0233 (4)
H3	0.6356	−0.0091	0.2780	0.028*
H4	0.7542	0.0152	0.3165	0.028*
C6	0.62677 (16)	−0.02577 (14)	0.39040 (10)	0.0210 (4)
H5	0.5761	0.0295	0.3990	0.025*
C7	0.56806 (16)	−0.12318 (14)	0.39241 (10)	0.0212 (4)
C8	0.51481 (18)	−0.14473 (16)	0.46468 (10)	0.0271 (5)
H6	0.4498	−0.1030	0.4725	0.041*
H7	0.5711	−0.1347	0.5023	0.041*
H8	0.4894	−0.2103	0.4656	0.041*
C9	0.47884 (17)	−0.13701 (15)	0.33435 (11)	0.0262 (4)
H9	0.4566	−0.2034	0.3325	0.039*
H10	0.5105	−0.1182	0.2883	0.039*
H11	0.4122	−0.0983	0.3451	0.039*
C10	0.67500 (19)	−0.28552 (14)	0.37539 (11)	0.0286 (5)
H12	0.7522	−0.3103	0.3708	0.043*
H13	0.6297	−0.3053	0.3343	0.043*
H14	0.6405	−0.3098	0.4191	0.043*
C11	0.88749 (15)	0.05697 (13)	0.57968 (10)	0.0181 (4)
C12	0.86509 (16)	0.22342 (13)	0.61970 (9)	0.0182 (4)
C13	0.77715 (16)	0.28713 (14)	0.62938 (10)	0.0204 (4)
H15	0.7051	0.2750	0.6088	0.025*
C14	0.79379 (17)	0.36801 (14)	0.66875 (10)	0.0236 (4)
H17	0.7334	0.4114	0.6750	0.028*
C15	0.89868 (18)	0.38574 (14)	0.69908 (10)	0.0240 (4)
H18	0.9103	0.4408	0.7268	0.029*
C16	0.98636 (17)	0.32276 (14)	0.68867 (10)	0.0237 (4)
H19	1.0583	0.3349	0.7095	0.028*
C17	0.97111 (16)	0.24224 (14)	0.64831 (10)	0.0210 (4)
H20	1.0326	0.2004	0.6403	0.025*
N1	0.75715 (13)	0.02268 (11)	0.48709 (8)	0.0193 (3)
N2	0.84297 (13)	−0.00435 (11)	0.53138 (8)	0.0193 (3)
H21	0.8698	−0.0620	0.5287	0.023*
N3	0.84240 (13)	0.14351 (11)	0.57670 (8)	0.0200 (3)
H22	0.7913	0.1520	0.5432	0.024*
O1	0.82511 (11)	−0.18192 (9)	0.47199 (7)	0.0223 (3)
S1	0.98673 (4)	0.01558 (4)	0.63485 (3)	0.02212 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0174 (9)	0.0210 (10)	0.0183 (9)	0.0009 (7)	−0.0013 (7)	0.0005 (7)
C2	0.0167 (9)	0.0216 (10)	0.0176 (9)	0.0007 (8)	0.0002 (8)	−0.0005 (7)
C3	0.0229 (10)	0.0205 (10)	0.0221 (10)	0.0016 (8)	−0.0038 (8)	−0.0036 (8)
C4	0.0201 (10)	0.0347 (12)	0.0187 (9)	0.0003 (9)	0.0001 (8)	−0.0026 (8)
C5	0.0205 (10)	0.0294 (11)	0.0201 (9)	−0.0058 (8)	−0.0017 (8)	0.0031 (8)
C6	0.0186 (9)	0.0221 (10)	0.0224 (9)	0.0017 (8)	−0.0037 (8)	−0.0026 (8)
C7	0.0198 (10)	0.0225 (10)	0.0214 (10)	−0.0012 (8)	−0.0010 (8)	0.0012 (8)
C8	0.0198 (10)	0.0387 (12)	0.0228 (10)	−0.0044 (9)	0.0017 (8)	0.0022 (9)
C9	0.0218 (10)	0.0276 (11)	0.0292 (11)	−0.0031 (9)	−0.0056 (9)	0.0003 (8)
C10	0.0357 (12)	0.0196 (10)	0.0305 (11)	0.0002 (9)	−0.0083 (9)	−0.0022 (9)
C11	0.0158 (9)	0.0219 (10)	0.0167 (9)	−0.0024 (7)	0.0021 (7)	−0.0011 (7)
C12	0.0199 (9)	0.0185 (9)	0.0161 (9)	−0.0016 (7)	0.0007 (7)	0.0008 (7)
C13	0.0170 (10)	0.0247 (10)	0.0196 (9)	0.0000 (7)	−0.0015 (7)	0.0018 (8)
C14	0.0237 (10)	0.0234 (10)	0.0238 (10)	0.0034 (8)	0.0016 (8)	0.0007 (8)
C15	0.0306 (11)	0.0203 (10)	0.0209 (10)	−0.0029 (8)	0.0011 (8)	−0.0015 (8)
C16	0.0202 (10)	0.0260 (11)	0.0249 (10)	−0.0049 (8)	−0.0027 (8)	0.0002 (8)
C17	0.0163 (9)	0.0227 (10)	0.0241 (10)	−0.0003 (8)	0.0003 (7)	−0.0003 (8)
N1	0.0161 (8)	0.0226 (9)	0.0193 (8)	0.0005 (7)	−0.0031 (6)	−0.0002 (7)
N2	0.0186 (8)	0.0195 (8)	0.0200 (8)	0.0026 (6)	−0.0041 (6)	−0.0021 (6)
N3	0.0187 (8)	0.0211 (8)	0.0204 (8)	0.0006 (7)	−0.0057 (6)	−0.0027 (6)
O1	0.0217 (7)	0.0240 (7)	0.0211 (7)	0.0056 (6)	−0.0030 (6)	0.0000 (6)
S1	0.0192 (2)	0.0241 (2)	0.0230 (2)	0.0002 (2)	−0.00591 (19)	0.00026 (19)

Geometric parameters (Å, º) top

C1—N1	1.283 (2)	C9—H11	0.9800
C1—C2	1.498 (3)	C10—H12	0.9800
C1—C6	1.500 (3)	C10—H13	0.9800
C2—O1	1.219 (2)	C10—H14	0.9800
C2—C3	1.513 (3)	C11—N3	1.342 (2)
C3—C10	1.499 (3)	C11—N2	1.364 (2)
C3—C7	1.562 (3)	C11—S1	1.6705 (19)
C3—C4	1.572 (3)	C12—C17	1.387 (3)
C4—C5	1.536 (3)	C12—C13	1.389 (3)
C4—H1	0.9900	C12—N3	1.420 (2)
C4—H2	0.9900	C13—C14	1.382 (3)
C5—C6	1.559 (3)	C13—H15	0.9500
C5—H3	0.9900	C14—C15	1.385 (3)
C5—H4	0.9900	C14—H17	0.9500
C6—C7	1.549 (3)	C15—C16	1.382 (3)
C6—H5	1.0000	C15—H18	0.9500
C7—C8	1.527 (3)	C16—C17	1.385 (3)
C7—C9	1.528 (3)	C16—H19	0.9500
C8—H6	0.9800	C17—H20	0.9500
C8—H7	0.9800	N1—N2	1.366 (2)
C8—H8	0.9800	N2—H21	0.8800
C9—H9	0.9800	N3—H22	0.8800
C9—H10	0.9800

N1—C1—C2	129.01 (17)	H7—C8—H8	109.5
N1—C1—C6	125.63 (17)	C7—C9—H9	109.5
C2—C1—C6	105.35 (16)	C7—C9—H10	109.5
O1—C2—C1	126.53 (17)	H9—C9—H10	109.5
O1—C2—C3	128.26 (18)	C7—C9—H11	109.5
C1—C2—C3	105.21 (15)	H9—C9—H11	109.5
C10—C3—C2	114.37 (17)	H10—C9—H11	109.5
C10—C3—C7	119.91 (18)	C3—C10—H12	109.5
C2—C3—C7	99.83 (15)	C3—C10—H13	109.5
C10—C3—C4	115.37 (17)	H12—C10—H13	109.5
C2—C3—C4	103.70 (15)	C3—C10—H14	109.5
C7—C3—C4	101.18 (15)	H12—C10—H14	109.5
C5—C4—C3	104.85 (15)	H13—C10—H14	109.5
C5—C4—H1	110.8	N3—C11—N2	113.96 (16)
C3—C4—H1	110.8	N3—C11—S1	128.81 (15)
C5—C4—H2	110.8	N2—C11—S1	117.21 (14)
C3—C4—H2	110.8	C17—C12—C13	119.77 (17)
H1—C4—H2	108.9	C17—C12—N3	123.02 (17)
C4—C5—C6	103.08 (15)	C13—C12—N3	117.11 (17)
C4—C5—H3	111.1	C14—C13—C12	120.47 (18)
C6—C5—H3	111.1	C14—C13—H15	119.8
C4—C5—H4	111.1	C12—C13—H15	119.8
C6—C5—H4	111.1	C13—C14—C15	119.91 (19)
H3—C5—H4	109.1	C13—C14—H17	120.0
C1—C6—C7	100.76 (15)	C15—C14—H17	120.0
C1—C6—C5	105.05 (15)	C16—C15—C14	119.48 (19)
C7—C6—C5	102.40 (15)	C16—C15—H18	120.3
C1—C6—H5	115.6	C14—C15—H18	120.3
C7—C6—H5	115.6	C15—C16—C17	121.07 (19)
C5—C6—H5	115.6	C15—C16—H19	119.5
C8—C7—C9	109.00 (16)	C17—C16—H19	119.5
C8—C7—C6	112.64 (16)	C16—C17—C12	119.26 (18)
C9—C7—C6	113.92 (16)	C16—C17—H20	120.4
C8—C7—C3	112.97 (16)	C12—C17—H20	120.4
C9—C7—C3	112.94 (16)	C1—N1—N2	116.47 (16)
C6—C7—C3	94.92 (15)	C11—N2—N1	120.72 (15)
C7—C8—H6	109.5	C11—N2—H21	119.6
C7—C8—H7	109.5	N1—N2—H21	119.6
H6—C8—H7	109.5	C11—N3—C12	129.47 (16)
C7—C8—H8	109.5	C11—N3—H22	115.3
H6—C8—H8	109.5	C12—N3—H22	115.3

N1—C1—C2—O1	0.0 (3)	C10—C3—C7—C8	62.0 (2)
C6—C1—C2—O1	−178.98 (18)	C2—C3—C7—C8	−63.6 (2)
N1—C1—C2—C3	179.61 (19)	C4—C3—C7—C8	−169.85 (16)
C6—C1—C2—C3	0.60 (19)	C10—C3—C7—C9	−62.3 (2)
O1—C2—C3—C10	15.6 (3)	C2—C3—C7—C9	172.08 (16)
C1—C2—C3—C10	−163.93 (17)	C4—C3—C7—C9	65.87 (19)
O1—C2—C3—C7	145.0 (2)	C10—C3—C7—C6	179.16 (17)
C1—C2—C3—C7	−34.58 (18)	C2—C3—C7—C6	53.51 (16)
O1—C2—C3—C4	−110.8 (2)	C4—C3—C7—C6	−52.71 (16)
C1—C2—C3—C4	69.58 (18)	C17—C12—C13—C14	−1.6 (3)
C10—C3—C4—C5	163.66 (17)	N3—C12—C13—C14	−178.03 (17)
C2—C3—C4—C5	−70.49 (18)	C12—C13—C14—C15	−0.2 (3)
C7—C3—C4—C5	32.65 (18)	C13—C14—C15—C16	1.0 (3)
C3—C4—C5—C6	1.47 (19)	C14—C15—C16—C17	0.1 (3)
N1—C1—C6—C7	−145.01 (19)	C15—C16—C17—C12	−1.9 (3)
C2—C1—C6—C7	34.04 (18)	C13—C12—C17—C16	2.6 (3)
N1—C1—C6—C5	108.9 (2)	N3—C12—C17—C16	178.86 (17)
C2—C1—C6—C5	−72.07 (18)	C2—C1—N1—N2	2.1 (3)
C4—C5—C6—C1	69.27 (18)	C6—C1—N1—N2	−179.05 (17)
C4—C5—C6—C7	−35.63 (18)	N3—C11—N2—N1	−2.4 (2)
C1—C6—C7—C8	63.84 (19)	S1—C11—N2—N1	176.39 (13)
C5—C6—C7—C8	172.04 (16)	C1—N1—N2—C11	−178.80 (17)
C1—C6—C7—C9	−171.36 (16)	N2—C11—N3—C12	177.82 (17)
C5—C6—C7—C9	−63.2 (2)	S1—C11—N3—C12	−0.8 (3)
C1—C6—C7—C3	−53.57 (16)	C17—C12—N3—C11	33.0 (3)
C5—C6—C7—C3	54.63 (16)	C13—C12—N3—C11	−150.65 (19)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H21···O1	0.88	2.08	2.769 (2)	135
N3—H22···N1	0.88	2.16	2.607 (2)	111

Acknowledgements

ABO is an associate researcher in the project `Dinitrosyl complexes containing thiol and/or thiosemicarbazone: synthesis, characterization and treatment against cancer', founded by FAPESP, Proc. 2015/12098–0, and acknowledges Professor José C. M. Pereira (São Paulo State University, Brazil) for his support during this work. ABO also acknowledges Professor Vanessa C. Gervini for the invitation to be a visiting professor at the Federal University of Rio Grande, Brazil, where this work was developed. The authors acknowledge Professor Manfredo Hörner (Federal University of Santa Maria, Brazil) for access to the experimental facilities.

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