3-[(Z)-Benzyl­idene]-2,3-dihydro-1,5-benzothia­zepin-4(5H)-one

Sabari, V.; Jagadeesan, G.; Selvakumar, R.; Bakthadoss, M.; Aravindhan, S.

doi:10.1107/S1600536811042991

organic compounds

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ISSN: 2056-9890

Volume 67| Part 11| November 2011| Page o3061

doi:10.1107/S1600536811042991

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3-[(Z)-Benzylidene]-2,3-dihydro-1,5-benzothiazepin-4(5H)-one

V. Sabari,^a G. Jagadeesan,^a Raman Selvakumar,^b Mannickam Bakthadoss ^b and S. Aravindhan ^a ^*

^aDepartment of Physics, Presidency College, Chennai 600 005, India, and ^bDepartment of Organic Chemistry, University of Madras, Chennai 600 025, India
^*Correspondence e-mail: aravindhanpresidency@gmail.com

(Received 13 October 2011; accepted 17 October 2011; online 29 October 2011)

In the title compound, C₁₆H₁₃NOS, the seven-membered ring adopts a distorted half-chair conformation. In the crystal, molecules are linked by N—H⋯O hydrogen bonds, forming chains running along the b axis. The crystal packing is further stabilized by C—H⋯O interactions.

Related literature

For the pharmaceutical properties of thiazepin derivatives, see: Tomascovic et al. (2000 ); Rajsner et al. (1971 ); Metys et al. (1965 ). For the conformation of thiazepin derivatives, see: Sridevi et al. (2011 ).

Experimental

Crystal data

C₁₆H₁₃NOS
M_r = 267.33
Orthorhombic, P b c a
a = 10.7711 (9) Å
b = 7.8736 (7) Å
c = 31.610 (3) Å
V = 2680.7 (4) Å³
Z = 8
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 293 K
0.2 × 0.2 × 0.2 mm

Data collection

Bruker KappaCCD APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.980, T_max = 0.990
13085 measured reflections
3306 independent reflections
2643 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.112
S = 1.04
3306 reflections
180 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N—H⋯Oⁱ	0.872 (18)	1.996 (18)	2.8480 (16)	165.4 (16)
C14—H14⋯Oⁱⁱ	0.93	2.57	3.485 (2)	167
C16—H16⋯O	0.93	2.60	3.397 (2)	144
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z]$ ; (ii) $[x+{\script{1\over 2}}, y, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811042991/bt5678sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811042991/bt5678Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811042991/bt5678Isup3.cml

checkCIF report

Comment top

The title compound is used as an intermediate for the synthesis of dosulepin, which is an antidepressant of the tricyclic family. Dosulepin prevents reabsorbing of serotonin and noradrenaline in the brain, helps to prolong the mood lightening effect of any released noradrenaline and serotonin, thus relieving depression. The dibenzo[c,e]thiazepin derivatives exhibit chiroptical properties (Tomascovic et al., 2000). Dibenzo[b,e]thiazepin-5,5-dioxide derivatives possess antihistaminic and antiallergenic activities (Rajsner et al., 1971). Benzene thiazepin derivatives are identified as a new type of effective antihistaminic compounds (Metys et al., 1965). Considering the wide range of biological activities of the thiazepin derivatives, we determined the crystal structure of the title compound. The seven membered thiazepin ring adopts a distorted half-chair conformation (Sridevi et al., 2011). Crystal structure and crystal packing of the molecule were stabilized by intra (C16—H16···O) and Inter (N—H···O, C14—H14···O) molecular interaction.

Related literature top

For the pharmaceutical properties of thiazepin derivatives, see: Tomascovic et al. (2000); Rajsner et al. (1971); Metys et al. (1965). For the conformation of thiazepin derivatives, see: Sridevi et al. (2011).

Experimental top

A mixture of (z)-methyl2-(bromomethyl)-3-phenylacrylate (2 mmol) and O-aminothiophenol(2 mmol) in the presence of potassium tert-butoxide (2,4 mmol) in dry THF (10 ml) was stirred at room temperature for 1 h. After the completion of the reaction as indicated by TLC, the reaction mixture was concentrated and the resulting crude mass was diluted with water (20 ml) and extracted with ethyl acetate (3X20ml). The organic layer was washed with brine (2X20ml) and dried over anhydrous sodium sulfate. The organic layer was concentrated, which provided a crude mass (Z)-methyl 2-((2-aminnophyenylthio)methyl)-3-phenylacrylate.The crude product was treated with a catalytic amount of p-toluene sulphonic acid (0.4 mmol),in p-xylene(10 ml), under reflux conditions for 12 h. After the completion of the reaction as indicated by TLC, the reaction mixture was concentrated under reduced pressure and worked up as mentioned previously, which successfully provide the crude final product. The final product was purified by column chromatography on silica gel to afford the title compound in good yield(71%).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 (Bruker, 2004); data reduction: APEX2 [or SAINT?] (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids for non-H atoms. H atoms have been omitted for clarity.
	Fig. 2. A view of the crystal packing H atoms not involved in hydrogen bonding (dashed lines) have been omitted for clarity.

3-[(Z)-Benzylidene]-2,3-dihydro-1,5-benzothiazepin-4(5H)-one top

Crystal data top

C₁₆H₁₃NOS	F(000) = 1120
M_r = 267.33	D_x = 1.325 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 8725 reflections
a = 10.7711 (9) Å	θ = 2.8–29.1°
b = 7.8736 (7) Å	µ = 0.23 mm⁻¹
c = 31.610 (3) Å	T = 293 K
V = 2680.7 (4) Å³	Orthorhombic, colourless
Z = 8	0.2 × 0.2 × 0.2 mm

Data collection top

Bruker KappaCCD APEXII diffractometer	3306 independent reflections
Radiation source: fine-focus sealed tube	2643 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
Detector resolution: 15.9948 pixels mm^-1	θ_max = 28.3°, θ_min = 1.3°
ω scans	h = −14→7
Absorption correction: multi-scan (APEX2; Bruker, 2004)	k = −5→10
T_min = 0.980, T_max = 0.990	l = −23→42
13085 measured reflections

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.112	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0544P)² + 0.6524P] where P = (F_o² + 2F_c²)/3
3306 reflections	(Δ/σ)_max = 0.002
180 parameters	Δρ_max = 0.35 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₆H₁₃NOS	V = 2680.7 (4) Å³
M_r = 267.33	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 10.7711 (9) Å	µ = 0.23 mm⁻¹
b = 7.8736 (7) Å	T = 293 K
c = 31.610 (3) Å	0.2 × 0.2 × 0.2 mm

Data collection top

Bruker KappaCCD APEXII diffractometer	3306 independent reflections
Absorption correction: multi-scan (APEX2; Bruker, 2004)	2643 reflections with I > 2σ(I)
T_min = 0.980, T_max = 0.990	R_int = 0.028
13085 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.112	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.35 e Å⁻³
3306 reflections	Δρ_min = −0.22 e Å⁻³
180 parameters

Special details top

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.

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 > σ(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
H10	1.0606 (16)	−0.099 (2)	0.6162 (5)	0.048 (5)*
H	0.8379 (16)	0.440 (2)	0.6294 (5)	0.042 (4)*
S	0.90221 (4)	0.20135 (6)	0.529568 (12)	0.04764 (14)
O	0.73812 (10)	0.16660 (13)	0.64118 (3)	0.0435 (3)
N	0.88207 (11)	0.35628 (15)	0.61960 (4)	0.0351 (3)
C8	0.90106 (16)	0.01129 (19)	0.56317 (5)	0.0461 (4)
H8A	0.8216	−0.0458	0.5605	0.055*
H8B	0.9653	−0.0665	0.5538	0.055*
C7	0.92280 (14)	0.05759 (17)	0.60855 (4)	0.0359 (3)
C6	0.83940 (13)	0.19642 (17)	0.62461 (4)	0.0333 (3)
C1	1.11685 (15)	0.3856 (2)	0.53349 (5)	0.0445 (4)
H1	1.1331	0.3404	0.5069	0.053*
C5	0.98953 (13)	0.39991 (16)	0.59611 (4)	0.0332 (3)
C2	1.19757 (16)	0.5031 (2)	0.55064 (6)	0.0494 (4)
H2	1.2669	0.5381	0.5354	0.059*
C4	1.07215 (15)	0.51731 (19)	0.61325 (5)	0.0432 (4)
H4	1.0580	0.5614	0.6401	0.052*
C9	1.01129 (14)	0.33387 (17)	0.55554 (4)	0.0359 (3)
C16	0.98687 (17)	0.1038 (2)	0.70536 (5)	0.0515 (4)
H16	0.9123	0.1553	0.6980	0.062*
C11	1.05193 (15)	0.01041 (19)	0.67530 (5)	0.0412 (3)
C3	1.17543 (16)	0.5686 (2)	0.59035 (6)	0.0494 (4)
H3	1.2300	0.6476	0.6019	0.059*
C13	1.2089 (2)	−0.0450 (3)	0.72861 (7)	0.0690 (6)
H13	1.2840	−0.0947	0.7362	0.083*
C14	1.1430 (2)	0.0472 (3)	0.75774 (7)	0.0667 (6)
H14	1.1730	0.0599	0.7851	0.080*
C10	1.01213 (15)	−0.01630 (18)	0.63123 (5)	0.0400 (3)
C12	1.16375 (17)	−0.0644 (2)	0.68770 (6)	0.0555 (4)
H12	1.2087	−0.1283	0.6683	0.067*
C15	1.0318 (2)	0.1210 (3)	0.74614 (6)	0.0626 (5)
H15	0.9867	0.1830	0.7659	0.075*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S	0.0540 (3)	0.0560 (3)	0.0329 (2)	−0.00587 (19)	−0.00722 (17)	−0.00413 (17)
O	0.0376 (6)	0.0446 (6)	0.0483 (6)	−0.0052 (5)	0.0072 (5)	−0.0052 (5)
N	0.0361 (7)	0.0308 (6)	0.0385 (6)	0.0026 (5)	0.0060 (5)	−0.0043 (5)
C8	0.0582 (10)	0.0399 (8)	0.0403 (8)	−0.0077 (7)	0.0035 (7)	−0.0108 (6)
C7	0.0417 (8)	0.0298 (6)	0.0361 (7)	−0.0036 (6)	0.0064 (6)	−0.0030 (5)
C6	0.0345 (7)	0.0355 (7)	0.0299 (6)	−0.0014 (6)	−0.0017 (5)	−0.0031 (5)
C1	0.0500 (9)	0.0433 (8)	0.0401 (8)	0.0036 (7)	0.0095 (7)	0.0038 (7)
C5	0.0341 (7)	0.0283 (6)	0.0372 (7)	0.0031 (5)	0.0010 (6)	0.0020 (5)
C2	0.0441 (9)	0.0434 (8)	0.0607 (10)	−0.0010 (7)	0.0135 (8)	0.0078 (7)
C4	0.0464 (9)	0.0358 (7)	0.0472 (9)	−0.0032 (7)	0.0022 (7)	−0.0056 (6)
C9	0.0388 (8)	0.0343 (7)	0.0345 (7)	0.0022 (6)	−0.0006 (6)	0.0018 (5)
C16	0.0490 (10)	0.0629 (10)	0.0425 (9)	0.0091 (8)	−0.0011 (7)	−0.0004 (8)
C11	0.0413 (8)	0.0367 (7)	0.0457 (8)	0.0010 (6)	0.0020 (7)	0.0063 (6)
C3	0.0447 (9)	0.0383 (8)	0.0652 (11)	−0.0079 (7)	0.0023 (8)	−0.0021 (7)
C13	0.0549 (11)	0.0700 (13)	0.0821 (14)	0.0031 (10)	−0.0195 (10)	0.0156 (11)
C14	0.0707 (13)	0.0733 (13)	0.0561 (11)	−0.0123 (11)	−0.0206 (10)	0.0097 (10)
C10	0.0448 (9)	0.0311 (7)	0.0442 (8)	0.0034 (6)	0.0101 (7)	−0.0017 (6)
C12	0.0491 (10)	0.0524 (10)	0.0649 (11)	0.0090 (8)	0.0010 (8)	0.0075 (8)
C15	0.0678 (13)	0.0746 (12)	0.0454 (9)	0.0002 (10)	−0.0033 (9)	−0.0049 (9)

Geometric parameters (Å, º) top

S—C9	1.7728 (15)	C2—H2	0.9300
S—C8	1.8352 (17)	C4—C3	1.387 (2)
O—C6	1.2326 (17)	C4—H4	0.9300
N—C6	1.3493 (18)	C16—C15	1.384 (2)
N—C5	1.4174 (18)	C16—C11	1.391 (2)
N—H	0.872 (18)	C16—H16	0.9300
C8—C7	1.498 (2)	C11—C12	1.397 (2)
C8—H8A	0.9700	C11—C10	1.473 (2)
C8—H8B	0.9700	C3—H3	0.9300
C7—C10	1.334 (2)	C13—C14	1.371 (3)
C7—C6	1.503 (2)	C13—C12	1.390 (3)
C6—O	1.2326 (17)	C13—H13	0.9300
C1—C2	1.381 (2)	C14—C15	1.381 (3)
C1—C9	1.394 (2)	C14—H14	0.9300
C1—H1	0.9300	C10—H10	0.962 (18)
C5—C4	1.393 (2)	C12—H12	0.9300
C5—C9	1.4037 (19)	C15—H15	0.9300
C2—C3	1.378 (2)

C9—S—C8	102.50 (7)	C5—C4—H4	119.9
C6—N—C5	124.46 (12)	C1—C9—C5	118.98 (14)
C6—N—H	118.7 (11)	C1—C9—S	118.75 (12)
C5—N—H	116.6 (11)	C5—C9—S	122.04 (11)
C7—C8—S	110.78 (10)	C15—C16—C11	120.80 (17)
C7—C8—H8A	109.5	C15—C16—H16	119.6
S—C8—H8A	109.5	C11—C16—H16	119.6
C7—C8—H8B	109.5	C16—C11—C12	117.75 (16)
S—C8—H8B	109.5	C16—C11—C10	125.11 (15)
H8A—C8—H8B	108.1	C12—C11—C10	117.14 (15)
C10—C7—C8	121.42 (14)	C2—C3—C4	120.34 (16)
C10—C7—C6	124.53 (13)	C2—C3—H3	119.8
C8—C7—C6	114.01 (13)	C4—C3—H3	119.8
O—C6—N	121.94 (13)	C14—C13—C12	120.12 (19)
O—C6—N	121.94 (13)	C14—C13—H13	119.9
O—C6—C7	122.26 (13)	C12—C13—H13	119.9
O—C6—C7	122.26 (13)	C13—C14—C15	119.60 (19)
N—C6—C7	115.79 (12)	C13—C14—H14	120.2
C2—C1—C9	120.89 (15)	C15—C14—H14	120.2
C2—C1—H1	119.6	C7—C10—C11	131.02 (14)
C9—C1—H1	119.6	C7—C10—H10	115.1 (11)
C4—C5—C9	119.65 (13)	C11—C10—H10	113.9 (11)
C4—C5—N	118.61 (13)	C13—C12—C11	121.10 (18)
C9—C5—N	121.68 (13)	C13—C12—H12	119.5
C3—C2—C1	119.96 (15)	C11—C12—H12	119.5
C3—C2—H2	120.0	C14—C15—C16	120.63 (19)
C1—C2—H2	120.0	C14—C15—H15	119.7
C3—C4—C5	120.17 (15)	C16—C15—H15	119.7
C3—C4—H4	119.9

C9—S—C8—C7	32.87 (13)	C4—C5—C9—C1	1.0 (2)
S—C8—C7—C10	−126.73 (14)	N—C5—C9—C1	178.07 (13)
S—C8—C7—C6	50.98 (16)	C4—C5—C9—S	−173.34 (11)
O—O—C6—N	0.0 (4)	N—C5—C9—S	3.70 (19)
O—O—C6—C7	0.0 (3)	C8—S—C9—C1	120.08 (13)
C5—N—C6—O	−171.54 (13)	C8—S—C9—C5	−65.54 (13)
C5—N—C6—O	−171.54 (13)	C15—C16—C11—C12	−0.2 (3)
C5—N—C6—C7	8.2 (2)	C15—C16—C11—C10	179.74 (17)
C10—C7—C6—O	−92.01 (19)	C1—C2—C3—C4	−0.1 (3)
C8—C7—C6—O	90.37 (16)	C5—C4—C3—C2	−0.4 (3)
C10—C7—C6—O	−92.01 (19)	C12—C13—C14—C15	−0.2 (3)
C8—C7—C6—O	90.37 (16)	C8—C7—C10—C11	178.60 (15)
C10—C7—C6—N	88.27 (18)	C6—C7—C10—C11	1.1 (3)
C8—C7—C6—N	−89.35 (16)	C16—C11—C10—C7	11.7 (3)
C6—N—C5—C4	−135.93 (15)	C12—C11—C10—C7	−168.36 (17)
C6—N—C5—C9	47.0 (2)	C14—C13—C12—C11	0.7 (3)
C9—C1—C2—C3	1.1 (2)	C16—C11—C12—C13	−0.5 (3)
C9—C5—C4—C3	0.0 (2)	C10—C11—C12—C13	179.57 (17)
N—C5—C4—C3	−177.16 (14)	C13—C14—C15—C16	−0.4 (3)
C2—C1—C9—C5	−1.6 (2)	C11—C16—C15—C14	0.6 (3)
C2—C1—C9—S	172.96 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N—H···Oⁱ	0.872 (18)	1.996 (18)	2.8480 (16)	165.4 (16)
C14—H14···Oⁱⁱ	0.93	2.57	3.485 (2)	167
C16—H16···O	0.93	2.60	3.397 (2)	144

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₃NOS
M_r	267.33
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	293
a, b, c (Å)	10.7711 (9), 7.8736 (7), 31.610 (3)
V (Å³)	2680.7 (4)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.2 × 0.2 × 0.2

Data collection
Diffractometer	Bruker KappaCCD APEXII diffractometer
Absorption correction	Multi-scan (APEX2; Bruker, 2004)
T_min, T_max	0.980, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	13085, 3306, 2643
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.112, 1.04
No. of reflections	3306
No. of parameters	180
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.22

Computer programs: APEX2 (Bruker, 2004), APEX2 [or SAINT?] (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N—H···Oⁱ	0.872 (18)	1.996 (18)	2.8480 (16)	165.4 (16)
C14—H14···Oⁱⁱ	0.93	2.57	3.485 (2)	166.6
C16—H16···O	0.93	2.60	3.397 (2)	144.4

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

Acknowledgements

SA thanks the UGC, India, for financial support.

References

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