Benzo[a][1,4]benzothia­zino[3,2-c]phenothia­zine

Bader, M.M.; Pham, P.-T.T.; Abu Khodair, S.S.; Saleh, M.I.

doi:10.1107/S2414314624003572

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 9| Part 4| April 2024| x240357

https://doi.org/10.1107/S2414314624003572

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Benzo[a][1,4]benzothiazino[3,2-c]phenothiazine

Mamoun M. Bader,^a ^* Phuong-Truc T. Pham,^b Salma S. Abu Khodair ^c and Maysoon I. Saleh ^d

^aDepartment of Chemistry, Alfaisal, University, Riyadh 15333, Saudi Arabia, ^bPenn State Scranton, Dunmore, Pennsylvania 18512, USA, ^cAlfasial University, Riyadh, Saudi Arabia, and ^dDepartment of Chemistry, The University of Jordan, Amman, Jordan
^*Correspondence e-mail: mbader@alfaisal.edu

Edited by S.-L. Zheng, Harvard University, USA (Received 3 April 2024; accepted 19 April 2024; online 30 April 2024)

The title compound, C₂₂H₁₂N₂S₂, crystallizes in space group P2₁/c with four molecules in the asymmetric unit. The heterocyclic molecule is quasi-planar with a dihedral angle between the phenyl rings on the periphery of the molecule of 1.73 (19)°. Short H⋯S (2.92 Å) and C—H⋯π [2.836 (3) Å] contacts are observed in the crystal with shorted π–π stacking distances of 3.438 (3) Å along the b axis. Surprisingly, and unlike a closely related material, this molecule readily forms large crystals by sublimation and by slow evaporation from dichloromethane. The maximum absorbance in the UV-Vis spectrum is at 533 nm. Emission was measured upon excitation at 533 nm with a fluorescence λ_max of 658 nm and cutoff of 900 nm.

Keywords: crystal structure; ladder oligomers; fused heterocyclic aromatics; dyes; donor/acceptor; organic semiconductors.

CCDC reference: 2349720

Structure description

Fused heterocyclic aromatic compounds are of interest as an alternative to oligoacenes (Spangler et al., 1989 ; McLean et al., 1989 , 1990 ; Pham et al., 2008 ). Surprisingly, despite this intensely researched area, structural studies of these materials are scarce. Sulfur-containing fused heterocyclic compounds, such as phenothiazine ladder polymers and oligomers are particularly interesting. Phenothiazine systems can be obtained readily by reaction of halo-p-benzoquinones and amino thiophenols (Agarwal & Schaefer, 1980 ; Okafor et al., 1988 ). The title compound was prepared as part of our work in crystalline organic semiconductors and was used in the construction of a single-crystal field effect transistor (Pham et al., 2008).

The molecule is quasi-planar (Fig. 1) with a dihedral angle between the C11–C16 and C17–C22 phenyl rings on the periphery of the molecule of 1.73 (19)°. Individual molecules stack along the b axis with π–π distances of 3.438 (3) Å between symmetry-related C3–C8 rings. The shortest interactions are H15⋯S1(1 − x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z) = 2.92 Å and C—H⋯π [H13⋯C13(2 − x, $[{1\over 2}]$ + z, $[{1\over 2}]$ − z)] of 2.84 Å. The packing of molecules is shown in Fig. 2.

Figure 1
Structure of title compound with 50% probability ellipsoids.

Figure 2
Packing of molecules governed by π-stacking and C—H⋯π contacts (H13⋯C13).

A survey of the Cambridge Structural Database (Groom et al., 2016 ) on March 28, 2024 revealed no hits for this compound or any closely related structures.

This class of compounds have unique optical and electrical properties (Spangler et al., 1989; Pham et al., 2008; McLean et al., 1990). The uv–vis spectra and florescence spectra are shown in Figs. 3 and 4. We note that the fluorescence cutoff spectra extend to 900 nm, which might be of interest for non-linear optical and biological applications.

Figure 3
Uv–vis spectrum of the title compound in DMF.

Figure 4
Emission spectrum of the title compound excited at 533 nm in DMF.

Synthesis and crystallization

The title compound was prepared followed published procedures (Feister et al., 2023 ; Okafor, 1988). In a typical experiment, 2,3-dichloro-1,4-naphthoquinone (1 mmol, 1.0693 g) was dissolved in 10 ml DMF. 2-Aminothiophenol (2 mmol, 1 ml) was added to the solution. The reaction was then left stirring for 10 h, and the product was vacuum filtered. The product was then dried for 10 h in a vacuum oven, and then recrystallized from a dichloromethane solution, resulting in a dark-purple solid (0.7974 g, yield 46%), m.p. 280°C. Suitable crystals were grown either by sublimation or by slow evaporation from dichloromethane.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1.

Table 1
Experimental details

Crystal data
Chemical formula	C₂₂H₁₂N₂S₂
M_r	368.46
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	11.7365 (5), 3.8149 (2), 35.7260 (15)
β (°)	97.669 (2)
V (Å³)	1585.27 (13)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.34
Crystal size (mm)	0.25 × 0.06 × 0.01

Data collection
Diffractometer	Bruker PHOTON-III CPAD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.642, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	13015, 3927, 3341
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.116, 1.06
No. of reflections	3927
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.52, −0.56
Computer programs: APEX4 and SAINT (Bruker, 2014 ), SHELXT2018/2 (Sheldrick, 2015a ), SHELXL2019/2 (Sheldrick, 2015b ) and SHELXTL (Sheldrick, 2008 ).

Structural data

CCDC reference: 2349720

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314624003572/oi4001sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314624003572/oi4001Isup5.hkl

checkCIF report

Computing details top

Benzo[a][1,4]benzothiazino[3,2-c]phenothiazine top

Crystal data top

C₂₂H₁₂N₂S₂	F(000) = 760
M_r = 368.46	D_x = 1.544 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.7365 (5) Å	Cell parameters from 2950 reflections
b = 3.8149 (2) Å	θ = 2.3–28.3°
c = 35.7260 (15) Å	µ = 0.34 mm⁻¹
β = 97.669 (2)°	T = 100 K
V = 1585.27 (13) Å³	Plate, brown
Z = 4	0.25 × 0.06 × 0.01 mm

Data collection top

Bruker PHOTON-III CPAD diffractometer	3341 reflections with I > 2σ(I)
Radiation source: micro-focus	R_int = 0.035
φ and ω scans	θ_max = 28.3°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −15→15
T_min = 0.642, T_max = 0.746	k = −3→5
13015 measured reflections	l = −47→43
3927 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.047	H-atom parameters constrained
wR(F²) = 0.116	w = 1/[σ²(F_o²) + (0.0466P)² + 2.0952P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
3927 reflections	Δρ_max = 0.52 e Å⁻³
235 parameters	Δρ_min = −0.56 e Å⁻³

Special details top

Experimental. Prof. M. Bader/ Prof. D. Alvacado / A. Bradley

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
S1	0.54183 (4)	0.21127 (14)	0.30740 (2)	0.01608 (13)
S2	0.33242 (4)	0.20563 (14)	0.34472 (2)	0.01608 (13)
C1	0.55313 (16)	0.3928 (5)	0.35287 (5)	0.0133 (4)
C2	0.66054 (16)	0.5414 (5)	0.37063 (5)	0.0136 (4)
C3	0.66375 (16)	0.6660 (5)	0.40993 (5)	0.0130 (4)
C4	0.76638 (17)	0.7994 (6)	0.42939 (6)	0.0161 (4)
H4	0.833194	0.811698	0.417086	0.019*
C5	0.77115 (17)	0.9132 (6)	0.46631 (6)	0.0173 (4)
H5	0.841216	1.001428	0.479273	0.021*
C6	0.67283 (17)	0.8986 (6)	0.48468 (6)	0.0171 (4)
H6	0.676060	0.977146	0.510033	0.021*
C7	0.57106 (17)	0.7691 (5)	0.46564 (6)	0.0158 (4)
H7	0.504467	0.759988	0.478081	0.019*
C8	0.56486 (16)	0.6513 (5)	0.42822 (5)	0.0139 (4)
C9	0.45459 (16)	0.5176 (5)	0.40854 (5)	0.0136 (4)
C10	0.45630 (16)	0.3844 (5)	0.37040 (5)	0.0131 (4)
N1	0.75471 (14)	0.5822 (5)	0.35518 (5)	0.0152 (3)
C11	0.76197 (17)	0.4805 (5)	0.31800 (6)	0.0149 (4)
C12	0.86667 (17)	0.5499 (6)	0.30445 (6)	0.0174 (4)
H12	0.926848	0.662186	0.320482	0.021*
C13	0.88363 (19)	0.4577 (6)	0.26821 (6)	0.0204 (4)
H13	0.955212	0.505662	0.259611	0.025*
C14	0.79652 (19)	0.2954 (6)	0.24432 (6)	0.0215 (5)
H14	0.808693	0.231235	0.219467	0.026*
C15	0.69185 (19)	0.2267 (6)	0.25667 (6)	0.0186 (4)
H15	0.632088	0.117180	0.240201	0.022*
C16	0.67390 (17)	0.3185 (5)	0.29338 (6)	0.0158 (4)
N2	0.36590 (14)	0.5329 (5)	0.42687 (5)	0.0157 (4)
C17	0.25691 (17)	0.4184 (6)	0.41125 (6)	0.0160 (4)
C18	0.16828 (17)	0.4541 (6)	0.43387 (6)	0.0178 (4)
H18	0.185008	0.553665	0.458358	0.021*
C19	0.05728 (17)	0.3472 (6)	0.42117 (6)	0.0197 (4)
H19	−0.001115	0.371277	0.437018	0.024*
C20	0.03085 (18)	0.2041 (6)	0.38515 (6)	0.0210 (4)
H20	−0.045527	0.132118	0.376360	0.025*
C21	0.11667 (17)	0.1672 (6)	0.36219 (6)	0.0182 (4)
H21	0.098693	0.071365	0.337562	0.022*
C22	0.22938 (17)	0.2703 (5)	0.37509 (6)	0.0155 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0154 (2)	0.0172 (3)	0.0152 (2)	−0.0022 (2)	0.00051 (17)	−0.00166 (19)
S2	0.0136 (2)	0.0180 (3)	0.0160 (2)	−0.0023 (2)	−0.00017 (17)	−0.00226 (19)
C1	0.0148 (9)	0.0119 (9)	0.0125 (9)	0.0016 (8)	−0.0013 (7)	0.0015 (7)
C2	0.0138 (9)	0.0115 (9)	0.0147 (9)	0.0007 (8)	−0.0007 (7)	0.0013 (7)
C3	0.0130 (8)	0.0111 (9)	0.0140 (9)	0.0009 (7)	−0.0012 (7)	0.0011 (7)
C4	0.0131 (8)	0.0160 (10)	0.0187 (10)	0.0001 (8)	0.0001 (7)	−0.0001 (8)
C5	0.0158 (9)	0.0164 (10)	0.0184 (10)	−0.0021 (8)	−0.0028 (7)	−0.0016 (8)
C6	0.0196 (10)	0.0165 (10)	0.0145 (9)	0.0015 (8)	−0.0003 (7)	−0.0014 (8)
C7	0.0154 (9)	0.0156 (10)	0.0161 (9)	−0.0001 (8)	0.0015 (7)	0.0009 (8)
C8	0.0136 (9)	0.0123 (9)	0.0148 (9)	0.0013 (8)	−0.0012 (7)	0.0006 (7)
C9	0.0139 (9)	0.0110 (9)	0.0150 (9)	0.0000 (8)	−0.0011 (7)	0.0017 (7)
C10	0.0116 (8)	0.0104 (9)	0.0160 (9)	−0.0003 (7)	−0.0025 (7)	0.0014 (7)
N1	0.0137 (8)	0.0155 (8)	0.0160 (8)	−0.0002 (7)	0.0001 (6)	−0.0003 (7)
C11	0.0167 (9)	0.0118 (9)	0.0163 (9)	0.0019 (8)	0.0018 (7)	0.0019 (7)
C12	0.0173 (9)	0.0137 (10)	0.0215 (10)	−0.0024 (8)	0.0035 (8)	0.0015 (8)
C13	0.0223 (10)	0.0167 (10)	0.0239 (11)	0.0020 (9)	0.0089 (8)	0.0024 (9)
C14	0.0299 (11)	0.0182 (10)	0.0175 (10)	0.0045 (9)	0.0068 (8)	0.0023 (8)
C15	0.0231 (10)	0.0153 (10)	0.0162 (10)	0.0016 (9)	−0.0013 (8)	−0.0002 (8)
C16	0.0185 (9)	0.0116 (9)	0.0172 (9)	0.0008 (8)	0.0020 (7)	0.0036 (8)
N2	0.0146 (8)	0.0158 (9)	0.0162 (8)	−0.0006 (7)	0.0006 (6)	0.0002 (7)
C17	0.0139 (9)	0.0148 (10)	0.0189 (10)	0.0014 (8)	0.0007 (7)	0.0031 (8)
C18	0.0168 (9)	0.0182 (10)	0.0182 (10)	0.0006 (8)	0.0022 (7)	0.0001 (8)
C19	0.0149 (9)	0.0196 (11)	0.0254 (11)	0.0016 (8)	0.0052 (8)	0.0032 (9)
C20	0.0130 (9)	0.0235 (11)	0.0252 (11)	−0.0022 (9)	−0.0021 (8)	0.0041 (9)
C21	0.0162 (9)	0.0168 (10)	0.0204 (10)	−0.0020 (8)	−0.0022 (7)	0.0001 (8)
C22	0.0139 (8)	0.0132 (10)	0.0187 (9)	0.0017 (8)	0.0002 (7)	0.0028 (8)

Geometric parameters (Å, º) top

S1—C16	1.740 (2)	C11—C12	1.405 (3)
S1—C1	1.755 (2)	C11—C16	1.407 (3)
S2—C22	1.747 (2)	C12—C13	1.382 (3)
S2—C10	1.751 (2)	C12—H12	0.9500
C1—C10	1.369 (3)	C13—C14	1.387 (3)
C1—C2	1.449 (3)	C13—H13	0.9500
C2—N1	1.309 (2)	C14—C15	1.385 (3)
C2—C3	1.478 (3)	C14—H14	0.9500
C3—C4	1.404 (3)	C15—C16	1.400 (3)
C3—C8	1.407 (3)	C15—H15	0.9500
C4—C5	1.382 (3)	N2—C17	1.396 (3)
C4—H4	0.9500	C17—C18	1.406 (3)
C5—C6	1.403 (3)	C17—C22	1.407 (3)
C5—H5	0.9500	C18—C19	1.383 (3)
C6—C7	1.384 (3)	C18—H18	0.9500
C6—H6	0.9500	C19—C20	1.394 (3)
C7—C8	1.403 (3)	C19—H19	0.9500
C7—H7	0.9500	C20—C21	1.389 (3)
C8—C9	1.479 (3)	C20—H20	0.9500
C9—N2	1.303 (2)	C21—C22	1.398 (3)
C9—C10	1.457 (3)	C21—H21	0.9500
N1—C11	1.398 (3)

C16—S1—C1	102.32 (10)	C12—C11—C16	118.08 (18)
C22—S2—C10	102.41 (10)	C13—C12—C11	121.1 (2)
C10—C1—C2	122.38 (18)	C13—C12—H12	119.4
C10—C1—S1	116.71 (15)	C11—C12—H12	119.4
C2—C1—S1	120.91 (14)	C12—C13—C14	120.25 (19)
N1—C2—C1	126.58 (18)	C12—C13—H13	119.9
N1—C2—C3	116.52 (17)	C14—C13—H13	119.9
C1—C2—C3	116.89 (16)	C15—C14—C13	120.1 (2)
C4—C3—C8	119.40 (18)	C15—C14—H14	120.0
C4—C3—C2	119.92 (17)	C13—C14—H14	120.0
C8—C3—C2	120.68 (17)	C14—C15—C16	120.1 (2)
C5—C4—C3	120.62 (18)	C14—C15—H15	119.9
C5—C4—H4	119.7	C16—C15—H15	119.9
C3—C4—H4	119.7	C15—C16—C11	120.35 (19)
C4—C5—C6	120.19 (19)	C15—C16—S1	117.50 (16)
C4—C5—H5	119.9	C11—C16—S1	122.11 (15)
C6—C5—H5	119.9	C9—N2—C17	122.41 (17)
C7—C6—C5	119.59 (19)	N2—C17—C18	116.65 (18)
C7—C6—H6	120.2	N2—C17—C22	125.35 (18)
C5—C6—H6	120.2	C18—C17—C22	118.00 (18)
C6—C7—C8	120.95 (18)	C19—C18—C17	121.3 (2)
C6—C7—H7	119.5	C19—C18—H18	119.3
C8—C7—H7	119.5	C17—C18—H18	119.3
C7—C8—C3	119.24 (18)	C18—C19—C20	120.15 (19)
C7—C8—C9	119.63 (17)	C18—C19—H19	119.9
C3—C8—C9	121.12 (17)	C20—C19—H19	119.9
N2—C9—C10	126.69 (18)	C21—C20—C19	119.70 (19)
N2—C9—C8	116.92 (17)	C21—C20—H20	120.1
C10—C9—C8	116.40 (16)	C19—C20—H20	120.1
C1—C10—C9	122.38 (17)	C20—C21—C22	120.4 (2)
C1—C10—S2	116.83 (15)	C20—C21—H21	119.8
C9—C10—S2	120.79 (14)	C22—C21—H21	119.8
C2—N1—C11	122.00 (17)	C21—C22—C17	120.46 (18)
N1—C11—C12	116.25 (18)	C21—C22—S2	117.29 (16)
N1—C11—C16	125.67 (18)	C17—C22—S2	122.25 (15)

C16—S1—C1—C10	173.32 (16)	C1—C2—N1—C11	−0.2 (3)
C16—S1—C1—C2	−7.01 (19)	C3—C2—N1—C11	−178.92 (17)
C10—C1—C2—N1	−175.1 (2)	C2—N1—C11—C12	177.87 (19)
S1—C1—C2—N1	5.3 (3)	C2—N1—C11—C16	−1.7 (3)
C10—C1—C2—C3	3.7 (3)	N1—C11—C12—C13	179.44 (19)
S1—C1—C2—C3	−175.95 (14)	C16—C11—C12—C13	−0.9 (3)
N1—C2—C3—C4	−3.8 (3)	C11—C12—C13—C14	0.4 (3)
C1—C2—C3—C4	177.34 (18)	C12—C13—C14—C15	0.4 (3)
N1—C2—C3—C8	176.48 (19)	C13—C14—C15—C16	−0.5 (3)
C1—C2—C3—C8	−2.4 (3)	C14—C15—C16—C11	−0.1 (3)
C8—C3—C4—C5	0.5 (3)	C14—C15—C16—S1	−177.97 (17)
C2—C3—C4—C5	−179.23 (19)	N1—C11—C16—C15	−179.62 (19)
C3—C4—C5—C6	−0.5 (3)	C12—C11—C16—C15	0.8 (3)
C4—C5—C6—C7	0.1 (3)	N1—C11—C16—S1	−1.9 (3)
C5—C6—C7—C8	0.2 (3)	C12—C11—C16—S1	178.56 (16)
C6—C7—C8—C3	−0.1 (3)	C1—S1—C16—C15	−176.64 (16)
C6—C7—C8—C9	−179.42 (19)	C1—S1—C16—C11	5.5 (2)
C4—C3—C8—C7	−0.2 (3)	C10—C9—N2—C17	−0.2 (3)
C2—C3—C8—C7	179.50 (18)	C8—C9—N2—C17	179.35 (18)
C4—C3—C8—C9	179.07 (19)	C9—N2—C17—C18	−179.1 (2)
C2—C3—C8—C9	−1.2 (3)	C9—N2—C17—C22	1.2 (3)
C7—C8—C9—N2	3.3 (3)	N2—C17—C18—C19	−179.7 (2)
C3—C8—C9—N2	−176.02 (19)	C22—C17—C18—C19	0.1 (3)
C7—C8—C9—C10	−177.15 (18)	C17—C18—C19—C20	−0.7 (3)
C3—C8—C9—C10	3.5 (3)	C18—C19—C20—C21	0.4 (3)
C2—C1—C10—C9	−1.3 (3)	C19—C20—C21—C22	0.5 (3)
S1—C1—C10—C9	178.35 (15)	C20—C21—C22—C17	−1.1 (3)
C2—C1—C10—S2	178.49 (15)	C20—C21—C22—S2	178.64 (17)
S1—C1—C10—S2	−1.8 (2)	N2—C17—C22—C21	−179.5 (2)
N2—C9—C10—C1	177.2 (2)	C18—C17—C22—C21	0.8 (3)
C8—C9—C10—C1	−2.3 (3)	N2—C17—C22—S2	0.8 (3)
N2—C9—C10—S2	−2.6 (3)	C18—C17—C22—S2	−178.90 (16)
C8—C9—C10—S2	177.87 (14)	C10—S2—C22—C21	177.42 (17)
C22—S2—C10—C1	−176.21 (16)	C10—S2—C22—C17	−2.8 (2)
C22—S2—C10—C9	3.60 (18)

Acknowledgements

Research Development Grants and Professional Development Grants from Penn State Scranton (PTP) and internal research grants [Alfaisal University IRG-2020 (MMB)] are highly appreciated. The authors acknowledge Dr Victor Young Jr of the X-ray Crystallographic Laboratory, Department of Chemistry at the University of Minnesota for the data collection.

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