(Z)-3-(4-Chloro­benz­yl)-1,5-benzothia­zepin-4(5H)-one

In the title compound, C₁₆H₁₂ClNOS, the seven-membered thia­zepine ring adopts a distorted twisted boat conformation. The dihedral angle between the least-squares planes of the 1,5-benzothia­zepine ring system and the benzene ring is 50.2 (1)°. In the crystal, pairs of N—H...O hydrogen bonds link centrosymmetrically related mol­ecules into dimers, generating R₂²(8) ring motifs. The crystal packing is further stabilized by π–π inter­actions [centroid–centroid distance = 3.763 (2) Å].

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.047
• wR factor = 0.118
• Data-to-parameter ratio = 17.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C14
PLAT334_ALERT_2_C Small Average Benzene  C-C Dist. C11    -C16           1.37 Ang.
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          7
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         18

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT007_ALERT_5_G Note: Number of Unrefined D-H Atoms ............          1
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check

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S1. Comment

The title compound is used as an intermediate for the synthesis of dosulepin, which is an anti-depressant 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 anti-histaminic and anti-allergenic activities (Rajsner et al., 1971). Benzene thiazepin derivatives are identified as a new type of effective anti-histaminic compounds (Metys et al., 1965). In view of this biological importance, the crystal structure of the title compound has been carried out and the results are presented here.

Fig. 1. shows the seven membered thiazepine ring (N1/S1/C1/C2/C7/C8/C9) to adopt a twisted-boat conformation as indicated by puckering parameters (Cremer & Pople, 1975) QT = 1.0015 (16) Å, θ₂ = 74.1 (1)°, φ₂ = 177.3 (1)° and φ₃ = 177.6 (4)°. The dihedral angle between the benzothiazepin ring system and the benzene ring is 50.2 (1)°. The geometric parameters of the title molecule agree well with those reported for similar structures (Sridevi et al., 2011; Sabari et al., 2011).

In the crystal packing (Fig. 2), centrosymmetrically related molecules are linked by N1—H1···O1 hydrogen bonds into cyclic R₂²(8) dimers (Bernstein et al., 1995). The crystal packing (Fig. 3) is further stabilized by intermolecular π—π interactions with a Cg—Cgⁱ separation of 3.763 (1) Å [Cg is the centroid of the C2–C7 benzene ring, symmetry code as in Fig. 3].

Related literature

For the pharmaceutical properties of thiazepin derivatives, see: Tomascovic et al. (2000); Rajsner et al. (1971); Metys et al. (1965). For related structures, see: Sridevi et al. (2011); Sabari et al. (2011); Selvakumar et al. (2012). . For ring-puckering parameters, see: Cremer & Pople (1975). For hydrogen-bond motifs, see: Bernstein et al. (1995).

S2. Experimental

A mixture of (Z)-methyl 2-(bromomethyl)-3-(4-chlorophenyl)acrylate (2 mmol) and o-aminothiophenol (2 mmol) in the presence of potassium tert-butoxide (4.8 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 (3 × 20 ml). The organic layer was washed with brine (2 × 20 ml) and dried over anhydrous sodium sulfate. The organic layer was concentrated, which successfully provided the crude final product. The final product was purified by column chromatography on silica gel to afford the title compound in good yield (43%).

S3. Refinement

H atoms were positioned geometrically, with C—H = 0.93–0.97 Å and N—H = 0.86 Å, and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(N,C).

Computing details

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

Figures

	Fig. 1. Molecular structure of the title compound showing displacement ellipsoids at the 30% probability level. H atoms are presented as a small spheres of arbitrary radii.
	Fig. 2. Part of the crystal structure of the title compound showing N—H···O intermolecular hydrogen bonds (dotted lines) generating an R^22(8) centrosymmetric dimer [Symmetry code: (i) -x, -y, -z].
	Fig. 3. A view of a π—π interaction (dotted lines) in the crystal structure of the title compound. Cg denotes centroid of the C2–C7 benzene ring [Symmetry code: (i) -x, 1 - y, -z].

(Z)-3-(4-Chlorobenzyl)-1,5-benzothiazepin-4(5H)-one

Crystal data

C16H12ClNOS	F(000) = 1248
Mr = 301.78	Dx = 1.406 Mg m^−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 3130 reflections
a = 9.0486 (3) Å	θ = 2.4–27.0°
b = 9.4105 (3) Å	µ = 0.41 mm^−1
c = 33.4876 (10) Å	T = 293 K
V = 2851.53 (16) Å^3	Block, colourless
Z = 8	0.23 × 0.21 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer	3099 independent reflections
Radiation source: fine-focus sealed tube	2382 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.029
Detector resolution: 10.0 pixels mm^-1	θmax = 27.0°, θmin = 2.4°
ω scans	h = −11→11
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −10→11
Tmin = 0.910, Tmax = 0.941	l = −42→29
14850 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.047	H-atom parameters constrained
wR(F^2) = 0.118	w = 1/[σ^2(Fo^2) + (0.0432P)^2 + 1.9074P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max < 0.001
3099 reflections	Δρmax = 0.35 e Å^−3
182 parameters	Δρmin = −0.45 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0057 (6)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	0.0719 (3)	0.1514 (2)	0.12513 (6)	0.0476 (5)
H1A	0.0655	0.1466	0.1528	0.057*
C2	0.0392 (2)	0.3707 (2)	0.07497 (6)	0.0435 (5)
C3	0.0021 (3)	0.5128 (3)	0.08041 (7)	0.0580 (7)
H3	0.0457	0.5643	0.1010	0.070*
C4	−0.0985 (3)	0.5777 (3)	0.05567 (8)	0.0618 (7)
H4	−0.1210	0.6733	0.0592	0.074*
C5	−0.1654 (3)	0.5023 (2)	0.02586 (8)	0.0518 (6)
H5	−0.2335	0.5466	0.0092	0.062*
C6	−0.1323 (2)	0.3610 (2)	0.02049 (7)	0.0434 (5)
H6	−0.1789	0.3098	0.0004	0.052*
C7	−0.0300 (2)	0.2947 (2)	0.04485 (6)	0.0373 (4)
C8	0.0158 (2)	0.0388 (2)	0.06027 (6)	0.0399 (5)
C9	0.0015 (2)	0.0533 (2)	0.10436 (6)	0.0416 (5)
C10	−0.0895 (3)	−0.0641 (3)	0.12279 (7)	0.0555 (6)
H10A	−0.1879	−0.0612	0.1114	0.067*
H10B	−0.0457	−0.1547	0.1156	0.067*
C11	−0.1027 (3)	−0.0572 (2)	0.16758 (7)	0.0489 (6)
C12	−0.0147 (3)	−0.1404 (3)	0.19132 (8)	0.0590 (6)
H12	0.0524	−0.2022	0.1794	0.071*
C13	−0.0233 (3)	−0.1346 (3)	0.23246 (8)	0.0668 (7)
H13	0.0367	−0.1922	0.2482	0.080*
C14	−0.1208 (3)	−0.0436 (3)	0.24963 (8)	0.0639 (7)
C15	−0.2101 (3)	0.0408 (3)	0.22704 (9)	0.0733 (8)
H15	−0.2766	0.1028	0.2391	0.088*
C16	−0.2004 (3)	0.0329 (3)	0.18587 (8)	0.0664 (7)
H16	−0.2614	0.0899	0.1703	0.080*
N1	0.0078 (2)	0.15261 (18)	0.03612 (5)	0.0405 (4)
H1	0.0290	0.1363	0.0115	0.049*
O1	0.0322 (2)	−0.08062 (16)	0.04596 (4)	0.0551 (4)
S1	0.17684 (7)	0.29044 (7)	0.104528 (18)	0.0568 (2)
Cl1	−0.13112 (12)	−0.03656 (12)	0.30146 (2)	0.1046 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0518 (13)	0.0530 (13)	0.0379 (11)	−0.0069 (11)	−0.0027 (10)	0.0015 (10)
C2	0.0495 (13)	0.0381 (12)	0.0428 (11)	−0.0122 (10)	0.0066 (9)	−0.0021 (9)
C3	0.0789 (18)	0.0400 (13)	0.0552 (14)	−0.0191 (13)	0.0111 (13)	−0.0109 (11)
C4	0.0796 (19)	0.0336 (12)	0.0721 (17)	0.0004 (12)	0.0225 (15)	−0.0012 (12)
C5	0.0508 (14)	0.0379 (12)	0.0667 (15)	0.0020 (11)	0.0135 (12)	0.0109 (11)
C6	0.0418 (11)	0.0363 (12)	0.0522 (12)	−0.0045 (9)	0.0039 (10)	0.0036 (9)
C7	0.0389 (11)	0.0328 (10)	0.0400 (10)	−0.0049 (9)	0.0067 (8)	−0.0009 (8)
C8	0.0440 (12)	0.0361 (12)	0.0396 (10)	0.0032 (9)	−0.0035 (9)	−0.0018 (9)
C9	0.0469 (12)	0.0398 (12)	0.0380 (10)	0.0010 (10)	−0.0028 (9)	0.0018 (9)
C10	0.0696 (16)	0.0478 (13)	0.0492 (13)	−0.0110 (12)	−0.0046 (12)	0.0040 (11)
C11	0.0515 (14)	0.0455 (13)	0.0497 (12)	−0.0084 (11)	−0.0005 (10)	0.0095 (10)
C12	0.0615 (16)	0.0559 (15)	0.0595 (14)	0.0044 (13)	−0.0010 (12)	0.0090 (12)
C13	0.0687 (18)	0.0723 (18)	0.0593 (15)	−0.0046 (15)	−0.0117 (14)	0.0210 (14)
C14	0.0653 (17)	0.0791 (18)	0.0472 (13)	−0.0228 (15)	0.0080 (12)	0.0081 (13)
C15	0.0719 (19)	0.078 (2)	0.0698 (17)	0.0061 (16)	0.0219 (15)	0.0040 (15)
C16	0.0631 (17)	0.0714 (18)	0.0645 (16)	0.0115 (14)	0.0025 (13)	0.0179 (14)
N1	0.0527 (11)	0.0347 (9)	0.0342 (8)	0.0024 (8)	0.0011 (8)	−0.0025 (7)
O1	0.0836 (12)	0.0365 (8)	0.0453 (8)	0.0120 (8)	−0.0058 (8)	−0.0030 (7)
S1	0.0541 (4)	0.0654 (4)	0.0509 (3)	−0.0224 (3)	−0.0093 (3)	0.0030 (3)
Cl1	0.1122 (7)	0.1522 (9)	0.0494 (4)	−0.0371 (7)	0.0121 (4)	0.0051 (5)

Geometric parameters (Å, º)

C1—C9	1.320 (3)	C8—C9	1.488 (3)
C1—S1	1.758 (2)	C9—C10	1.509 (3)
C1—H1A	0.9300	C10—C11	1.506 (3)
C2—C7	1.386 (3)	C10—H10A	0.9700
C2—C3	1.391 (3)	C10—H10B	0.9700
C2—S1	1.761 (2)	C11—C16	1.370 (4)
C3—C4	1.374 (4)	C11—C12	1.371 (3)
C3—H3	0.9300	C12—C13	1.381 (4)
C4—C5	1.366 (4)	C12—H12	0.9300
C4—H4	0.9300	C13—C14	1.357 (4)
C5—C6	1.374 (3)	C13—H13	0.9300
C5—H5	0.9300	C14—C15	1.363 (4)
C6—C7	1.382 (3)	C14—Cl1	1.739 (3)
C6—H6	0.9300	C15—C16	1.383 (4)
C7—N1	1.411 (3)	C15—H15	0.9300
C8—O1	1.231 (2)	C16—H16	0.9300
C8—N1	1.344 (3)	N1—H1	0.8600
C9—C1—S1	125.10 (17)	C11—C10—H10A	108.6
C9—C1—H1A	117.5	C9—C10—H10A	108.6
S1—C1—H1A	117.5	C11—C10—H10B	108.6
C7—C2—C3	118.8 (2)	C9—C10—H10B	108.6
C7—C2—S1	120.49 (17)	H10A—C10—H10B	107.6
C3—C2—S1	120.64 (18)	C16—C11—C12	118.0 (2)
C4—C3—C2	120.6 (2)	C16—C11—C10	121.6 (2)
C4—C3—H3	119.7	C12—C11—C10	120.5 (2)
C2—C3—H3	119.7	C11—C12—C13	121.5 (3)
C5—C4—C3	120.2 (2)	C11—C12—H12	119.2
C5—C4—H4	119.9	C13—C12—H12	119.2
C3—C4—H4	119.9	C14—C13—C12	119.0 (3)
C4—C5—C6	120.1 (2)	C14—C13—H13	120.5
C4—C5—H5	120.0	C12—C13—H13	120.5
C6—C5—H5	120.0	C13—C14—C15	121.2 (3)
C5—C6—C7	120.4 (2)	C13—C14—Cl1	118.8 (2)
C5—C6—H6	119.8	C15—C14—Cl1	120.0 (2)
C7—C6—H6	119.8	C14—C15—C16	118.9 (3)
C6—C7—C2	119.92 (19)	C14—C15—H15	120.5
C6—C7—N1	117.91 (18)	C16—C15—H15	120.5
C2—C7—N1	122.02 (19)	C11—C16—C15	121.3 (3)
O1—C8—N1	119.98 (18)	C11—C16—H16	119.3
O1—C8—C9	118.70 (18)	C15—C16—H16	119.3
N1—C8—C9	121.31 (18)	C8—N1—C7	130.05 (17)
C1—C9—C8	123.0 (2)	C8—N1—H1	115.0
C1—C9—C10	124.05 (19)	C7—N1—H1	115.0
C8—C9—C10	112.71 (18)	C1—S1—C2	99.08 (10)
C11—C10—C9	114.76 (19)
C7—C2—C3—C4	−1.7 (3)	C9—C10—C11—C16	79.7 (3)
S1—C2—C3—C4	175.82 (19)	C9—C10—C11—C12	−99.3 (3)
C2—C3—C4—C5	1.3 (4)	C16—C11—C12—C13	0.1 (4)
C3—C4—C5—C6	0.0 (4)	C10—C11—C12—C13	179.1 (2)
C4—C5—C6—C7	−0.7 (3)	C11—C12—C13—C14	−0.4 (4)
C5—C6—C7—C2	0.2 (3)	C12—C13—C14—C15	0.4 (4)
C5—C6—C7—N1	−175.39 (19)	C12—C13—C14—Cl1	−179.9 (2)
C3—C2—C7—C6	1.0 (3)	C13—C14—C15—C16	0.0 (4)
S1—C2—C7—C6	−176.59 (15)	Cl1—C14—C15—C16	−179.7 (2)
C3—C2—C7—N1	176.41 (19)	C12—C11—C16—C15	0.3 (4)
S1—C2—C7—N1	−1.2 (3)	C10—C11—C16—C15	−178.7 (2)
S1—C1—C9—C8	6.9 (3)	C14—C15—C16—C11	−0.3 (4)
S1—C1—C9—C10	−179.25 (19)	O1—C8—N1—C7	170.5 (2)
O1—C8—C9—C1	135.4 (2)	C9—C8—N1—C7	−8.1 (3)
N1—C8—C9—C1	−46.0 (3)	C6—C7—N1—C8	−131.7 (2)
O1—C8—C9—C10	−39.0 (3)	C2—C7—N1—C8	52.8 (3)
N1—C8—C9—C10	139.5 (2)	C9—C1—S1—C2	58.0 (2)
C1—C9—C10—C11	3.5 (3)	C7—C2—S1—C1	−60.21 (19)
C8—C9—C10—C11	177.9 (2)	C3—C2—S1—C1	122.26 (19)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.86	2.07	2.854 (2)	151

Symmetry code: (i) −x, −y, −z.