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ISSN: 2414-3146

(6-Bromo-2-oxo-2H-chromen-4-yl)methyl di­ethyl­carbamodi­thio­ate

aDepartment of Physics, Sri D Devaraja Urs Govt. First Grade College, Hunsur-571105, Mysore District, Karnataka, India, bDepartment of Physics, Yuvaraja's College (Constituent College), University of Mysore, Mysore-570005, Karnataka, India, and cDepartment of Chemistry, Karnatak University's Karnatak Science College, Dharwad, Karnataka 580001, India
*Correspondence e-mail: devarajegowda@yahoo.com

Edited by R. J. Butcher, Howard University, USA (Received 27 December 2015; accepted 4 January 2016; online 28 January 2016)

In the title compound, C15H16BrNO2S2, the 2H-chromene ring system is nearly planar, with a maximum deviation of 0.0182 (22) Å. In the crystal, ππ inter­actions between pyran and benzene rings of chromene [shortest centroid–centroid distance = 3.7588 (14) Å] occur.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Coumarin derivatives are an inter­esting class of heterocyclic system since the coumarin ring is an essential core moiety in a variety of natural and synthetic biologically active compounds. Coumarin and its derivatives are a group of lactones derived from phenols. Alternately stated, a coumarin ring system is formed by the fusion of benzene and 1,2-pyrone ring. The structure of benzopyrone has many advantages including high fluorescence quantum yield, large Stokes shift, excellent light stability, and low toxicity (Zhou et al., 2010[Zhou, S., Jia, J., Gao, J., Han, L., Li, Y. & Sheng, W. (2010). Dyes Pigments, 86, 123-128.]; Sato et al., 2008[Sato, S., Suzuki, M., Soma, T. & Tsunoda, M. (2008). Spectrochim. Acta A, 70, 799-804.]; Singh et al., 2011[Singh, R. K., Mandal, T., Balasubramanian, N., Cook, G. & Srivastava, D. K. (2011). Anal. Biochem. 408, 309-315.]). A series of di­thio­carbamate compounds have been synthesized and found to possess in vitro and in vivo anti­tumor activity (Li et al., 2004[Li, R. T., Cheng, T. M. & Cui, J. R. (2004). CN Patent 01118399.3.]; Guo et al., 2004[Guo, W., Ran, F. X., Wang, R. Q., Cui, J. R., Li, R. T., Cheng, T. M. & Ge, Z. M. (2004). Chin. J. Clin. Pharmacol. Ther. 9, 59-62.]). In an effort to look for the possible non-classical anti­folates acting as anti­tumor agents, we were inter­ested in the incorporation of the di­thio­carbamate moiety with coumarin. Herein we report the synthesis, and structural characterization of (6-bromo-2-oxo-2H-chromen-4-yl)methyl di­ethyl­carbamodi­thio­ate.

The asymmetric unit of (6-bromo-2-oxo-2H-chromen-4-yl)methyl di­ethyl­carbamodi­thio­ate is shown in Fig. 1[link]. The 2H-chromene ring system (O4/C7–C15) is nearly planar, with a maximum deviation of 0.018 (2) Å for atom C13. In the crystal, ππ inter­actions between pyran (O4/C9/C10/C13–C15) and benzene rings of chromene [shortest centroid–centroid distance = 3.7588 (14) Å] occur.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.

Synthesis and crystallization

All the chemicals used were of analytical reagent grade and were used directly without further purification. The title compound was synthesized according to the reported method (Kumar et al., 2012[Kumar, K. M., Devarajegowda, H. C., Jeyaseelan, S., Mahabaleshwaraiah, N. M. & Kotresh, O. (2012). Acta Cryst. E68, o1657.]). The compound was recrystallized from an ethanol–chloro­form mixture (v/v = 2/1) by slow evaporation at room temperature. Yield = 72%, m.p. 401–403 K; IR (KBr, cm−1): 985, 1141, 1201, 1410, 1492, and 1730. GCMS: m/e: 386. 1H NMR (400 MHz, CDCl3, δ, p.p.m): 7.74 (s, 1H, Ar—H), 7.51 (dd, 1H, Ar—H), 7.31 (t, 1H, Ar—H), 6.62 (s, 1H, Ar—H), 4.72 (s, 2H, CH2), 4.07 (q, 2H, CH2), 3.80 (q, 2H, CH2), 1.34 (q, 6H, CH3). Elemental analysis for C15H16BrNO2S2: C, 46.63; H, 4.17; N, 3.63 (calculated); C, 46.67; H, 4.12; N, 3.68(found).

Refinement

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

Table 1
Experimental details

Crystal data
Chemical formula C15H16BrNO2S2
Mr 386.32
Crystal system, space group Monoclinic, P21/n
Temperature (K) 296
a, b, c (Å) 7.8958 (2), 8.0536 (2), 25.2735 (8)
β (°) 97.909 (2)
V3) 1591.84 (8)
Z 4
Radiation type Mo Kα
μ (mm−1) 2.85
Crystal size (mm) 0.24 × 0.20 × 0.12
 
Data collection
Diffractometer Bruker SMART CCD area-detector
Absorption correction Multi-scan (SADABS; Sheldrick, 2007[Sheldrick, G. M. (2007). SADABS. University of Göttingen, Germany.])
Tmin, Tmax 0.770, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 12640, 2806, 2419
Rint 0.033
(sin θ/λ)max−1) 0.595
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.074, 1.04
No. of reflections 2806
No. of parameters 191
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.62, −0.44
Computer programs: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SAINT (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014/7 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), SHELXL2014/7.

Structural data


Comment top

Coumarin derivatives are an interesting class of heterocyclic system since the coumarin ring is an essential core moiety in a variety of natural and synthetic biologically active compounds. Coumarin and its derivatives are a group of lactones derived from phenols. Alternately stated, a coumarin ring system is formed by the fusion of benzene and 1,2-pyrone ring. The structure of benzopyrone has many advantages including high fluorescence quantum yield, large Stokes shift, excellent light stability, and low toxicity [(Zhou et al., 2010); (Sato et al., 2008); (Singh et al., 2011)]. A series of dithiocarbamate compounds have been synthesized and found to possess in vitro and in vivo antitumor activity [(Li et al., 2004); (Guo et al., 2004)]. In an effort to look for the possible non-classical antifolates acting as antitumor agents, we were interested in the incorporation of the dithiocarbamate moiety with coumarin. Herein we report the synthesis, and structural characterization of (6-bromo-2-oxo-2H-chromen-4-yl)methyl diethylcarbamodithioate.

The asymmetric unit of (6-bromo-2-oxo-2H-chromen-4-yl)methyl diethylcarbamodithioate is shown in Fig. 1. The 2H-chromene ring systems (O4/C7–C15) is nearly planar, with a maximum deviation of 0.0182 (22) Å for atom C13. In the crystal structure, inversion-related C—H···Br hydrogen bonds form inversion dimers with an R2 2(7) ring motif. In addition, weak intramolecular C—H···O hydrogen bonds along with ππ interactions between pyran (O4/C9/C10/C13–C15) and benzene rings of chromene [shortest centroid–centroid distance = 3.7588 (14) Å], stabilize the crystal packing.

Experimental top

All the chemicals used were of analytical reagent grade and were used directly without further purification. The title compound was synthesized according to the reported method (Kumar et al., 2012). The compound was recrystallized from an ethanol–chloroform mixture (v/v = 2/1) by slow evaporation at room temperature. Yield = 72%, m.p. 401–403 K; IR (KBr, cm−1): 985, 1141, 1201, 1410, 1492, and 1730. GCMS: m/e: 386. 1H NMR (400 MHz, CDCl3, δ, p.p.m): 7.74 (s, 1H, Ar—H), 7.51 (dd, 1H, Ar—H), 7.31 (t, 1H, Ar—H), 6.62 (s, 1H, Ar—H), 4.72 (s, 2H, CH2), 4.07 (q, 2H, CH2), 3.80 (q, 2H, CH2), 1.34 (q, 6H, CH3). Elemental analysis for C15H16BrNO2S2: C, 46.63; H, 4.17; N, 3.63 (calculated); C, 46.67; H, 4.12; N, 3.68(found).

Refinement top

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

Structure description top

Coumarin derivatives are an interesting class of heterocyclic system since the coumarin ring is an essential core moiety in a variety of natural and synthetic biologically active compounds. Coumarin and its derivatives are a group of lactones derived from phenols. Alternately stated, a coumarin ring system is formed by the fusion of benzene and 1,2-pyrone ring. The structure of benzopyrone has many advantages including high fluorescence quantum yield, large Stokes shift, excellent light stability, and low toxicity (Zhou et al., 2010; Sato et al., 2008; Singh et al., 2011). A series of dithiocarbamate compounds have been synthesized and found to possess in vitro and in vivo antitumor activity (Li et al., 2004; Guo et al., 2004). In an effort to look for the possible non-classical antifolates acting as antitumor agents, we were interested in the incorporation of the dithiocarbamate moiety with coumarin. Herein we report the synthesis, and structural characterization of (6-bromo-2-oxo-2H-chromen-4-yl)methyl diethylcarbamodithioate.

The asymmetric unit of (6-bromo-2-oxo-2H-chromen-4-yl)methyl diethylcarbamodithioate is shown in Fig. 1. The 2H-chromene ring system (O4/C7–C15) is nearly planar, with a maximum deviation of 0.018 (2) Å for atom C13. In the crystal, ππ interactions between pyran (O4/C9/C10/C13–C15) and benzene rings of chromene [shortest centroid–centroid distance = 3.7588 (14) Å] occur.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL2014/7.

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
(6-Bromo-2-oxo-2H-chromen-4-yl)methyl diethylcarbamodithioate top
Crystal data top
C15H16BrNO2S2Dx = 1.612 Mg m3
Mr = 386.32Melting point: 401 K
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 7.8958 (2) ÅCell parameters from 2806 reflections
b = 8.0536 (2) Åθ = 2.8–25.0°
c = 25.2735 (8) ŵ = 2.85 mm1
β = 97.909 (2)°T = 296 K
V = 1591.84 (8) Å3Plate, colourless
Z = 40.24 × 0.20 × 0.12 mm
F(000) = 784
Data collection top
Bruker SMART CCD area-detector
diffractometer
2806 independent reflections
Radiation source: fine-focus sealed tube2419 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ω and φ scansθmax = 25.0°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
h = 99
Tmin = 0.770, Tmax = 1.000k = 99
12640 measured reflectionsl = 3028
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.030 w = 1/[σ2(Fo2) + (0.0341P)2 + 0.9395P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.074(Δ/σ)max = 0.003
S = 1.04Δρmax = 0.62 e Å3
2806 reflectionsΔρmin = 0.44 e Å3
191 parametersExtinction correction: SHELXL2014/7 (Sheldrick 2015, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0078 (6)
Crystal data top
C15H16BrNO2S2V = 1591.84 (8) Å3
Mr = 386.32Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.8958 (2) ŵ = 2.85 mm1
b = 8.0536 (2) ÅT = 296 K
c = 25.2735 (8) Å0.24 × 0.20 × 0.12 mm
β = 97.909 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2806 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
2419 reflections with I > 2σ(I)
Tmin = 0.770, Tmax = 1.000Rint = 0.033
12640 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0300 restraints
wR(F2) = 0.074H-atom parameters constrained
S = 1.04Δρmax = 0.62 e Å3
2806 reflectionsΔρmin = 0.44 e Å3
191 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.59128 (4)1.00761 (4)1.10054 (2)0.05696 (14)
S20.97175 (8)0.75097 (8)0.86560 (2)0.03566 (17)
S30.60724 (8)0.65728 (8)0.82431 (3)0.03919 (18)
O40.7447 (2)0.3444 (2)1.01068 (7)0.0385 (4)
O50.8515 (3)0.1807 (2)0.95411 (8)0.0511 (5)
N60.8656 (2)0.6584 (2)0.76765 (8)0.0327 (4)
C70.6395 (3)0.8010 (3)1.06954 (10)0.0366 (6)
C80.7109 (3)0.7968 (3)1.02306 (10)0.0336 (5)
H80.73470.89511.00620.040*
C90.7477 (3)0.6432 (3)1.00118 (9)0.0306 (5)
C100.7105 (3)0.5005 (3)1.02818 (10)0.0324 (5)
C110.6357 (3)0.5063 (3)1.07453 (11)0.0409 (6)
H110.61030.40871.09150.049*
C120.5995 (3)0.6573 (3)1.09518 (11)0.0430 (6)
H120.54850.66321.12620.052*
C130.8253 (3)0.6230 (3)0.95250 (9)0.0291 (5)
C140.8597 (3)0.4683 (3)0.93707 (10)0.0332 (5)
H140.91100.45550.90630.040*
C150.8213 (3)0.3214 (3)0.96566 (10)0.0362 (6)
C160.8615 (3)0.7774 (3)0.92238 (10)0.0340 (5)
H16A0.92830.85210.94720.041*
H16B0.75340.83180.91050.041*
C170.8095 (3)0.6840 (3)0.81439 (9)0.0285 (5)
C181.0413 (3)0.6957 (4)0.75752 (11)0.0465 (7)
H18A1.08860.78220.78190.056*
H18B1.03730.73800.72140.056*
C191.1578 (4)0.5469 (5)0.76417 (16)0.0681 (9)
H19A1.26980.57830.75710.102*
H19B1.16450.50580.80010.102*
H19C1.11320.46160.73960.102*
C200.7533 (3)0.5899 (3)0.72156 (10)0.0406 (6)
H20A0.67000.51720.73440.049*
H20B0.82140.52340.70040.049*
C210.6610 (5)0.7204 (4)0.68662 (12)0.0607 (8)
H21A0.59000.66840.65740.091*
H21B0.59110.78510.70700.091*
H21C0.74260.79140.67300.091*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0733 (2)0.04765 (19)0.0528 (2)0.00713 (14)0.01885 (16)0.01305 (14)
S20.0369 (3)0.0427 (4)0.0276 (3)0.0064 (3)0.0053 (2)0.0020 (3)
S30.0343 (3)0.0448 (4)0.0391 (4)0.0033 (3)0.0073 (3)0.0049 (3)
O40.0511 (10)0.0296 (9)0.0359 (10)0.0034 (7)0.0102 (8)0.0035 (7)
O50.0772 (13)0.0281 (10)0.0493 (12)0.0013 (9)0.0127 (10)0.0027 (8)
N60.0408 (11)0.0318 (10)0.0262 (11)0.0029 (8)0.0070 (8)0.0011 (8)
C70.0394 (13)0.0387 (13)0.0318 (14)0.0032 (10)0.0054 (10)0.0051 (11)
C80.0378 (13)0.0321 (13)0.0309 (14)0.0005 (10)0.0045 (10)0.0021 (10)
C90.0301 (11)0.0329 (12)0.0278 (13)0.0012 (9)0.0006 (9)0.0020 (10)
C100.0349 (12)0.0314 (12)0.0304 (13)0.0017 (9)0.0024 (10)0.0013 (10)
C110.0472 (15)0.0410 (15)0.0367 (15)0.0059 (11)0.0137 (12)0.0087 (12)
C120.0481 (15)0.0519 (16)0.0315 (14)0.0010 (12)0.0147 (12)0.0030 (12)
C130.0314 (11)0.0313 (12)0.0239 (12)0.0020 (9)0.0007 (9)0.0003 (10)
C140.0412 (13)0.0324 (13)0.0252 (12)0.0011 (10)0.0019 (10)0.0007 (10)
C150.0429 (14)0.0326 (14)0.0317 (14)0.0018 (10)0.0001 (11)0.0008 (11)
C160.0465 (14)0.0293 (12)0.0269 (13)0.0020 (10)0.0075 (10)0.0012 (10)
C170.0402 (13)0.0214 (10)0.0237 (12)0.0005 (9)0.0042 (10)0.0060 (9)
C180.0487 (15)0.0560 (17)0.0384 (16)0.0092 (13)0.0190 (12)0.0017 (13)
C190.0454 (17)0.084 (2)0.076 (2)0.0058 (16)0.0126 (16)0.016 (2)
C200.0592 (16)0.0317 (13)0.0305 (14)0.0043 (11)0.0043 (11)0.0047 (11)
C210.090 (2)0.0470 (17)0.0392 (17)0.0020 (15)0.0134 (15)0.0049 (14)
Geometric parameters (Å, º) top
Br1—C71.900 (2)C12—H120.9300
S2—C171.775 (2)C13—C141.344 (3)
S2—C161.791 (2)C13—C161.506 (3)
S3—C171.664 (2)C14—C151.440 (3)
O4—C101.371 (3)C14—H140.9300
O4—C151.372 (3)C16—H16A0.9700
O5—C151.203 (3)C16—H16B0.9700
N6—C171.333 (3)C18—C191.506 (4)
N6—C201.471 (3)C18—H18A0.9700
N6—C181.476 (3)C18—H18B0.9700
C7—C81.372 (3)C19—H19A0.9600
C7—C121.384 (4)C19—H19B0.9600
C8—C91.402 (3)C19—H19C0.9600
C8—H80.9300C20—C211.496 (4)
C9—C101.389 (3)C20—H20A0.9700
C9—C131.457 (3)C20—H20B0.9700
C10—C111.383 (4)C21—H21A0.9600
C11—C121.369 (4)C21—H21B0.9600
C11—H110.9300C21—H21C0.9600
C17—S2—C16103.82 (11)C13—C16—H16A108.0
C10—O4—C15121.33 (18)S2—C16—H16A108.0
C17—N6—C20121.4 (2)C13—C16—H16B108.0
C17—N6—C18123.9 (2)S2—C16—H16B108.0
C20—N6—C18114.7 (2)H16A—C16—H16B107.3
C8—C7—C12121.9 (2)N6—C17—S3123.80 (18)
C8—C7—Br1120.24 (19)N6—C17—S2113.48 (17)
C12—C7—Br1117.90 (19)S3—C17—S2122.72 (14)
C7—C8—C9119.4 (2)N6—C18—C19113.1 (2)
C7—C8—H8120.3N6—C18—H18A109.0
C9—C8—H8120.3C19—C18—H18A109.0
C10—C9—C8117.9 (2)N6—C18—H18B109.0
C10—C9—C13117.7 (2)C19—C18—H18B109.0
C8—C9—C13124.4 (2)H18A—C18—H18B107.8
O4—C10—C11115.5 (2)C18—C19—H19A109.5
O4—C10—C9122.4 (2)C18—C19—H19B109.5
C11—C10—C9122.1 (2)H19A—C19—H19B109.5
C12—C11—C10119.3 (2)C18—C19—H19C109.5
C12—C11—H11120.4H19A—C19—H19C109.5
C10—C11—H11120.4H19B—C19—H19C109.5
C11—C12—C7119.4 (2)N6—C20—C21113.3 (2)
C11—C12—H12120.3N6—C20—H20A108.9
C7—C12—H12120.3C21—C20—H20A108.9
C14—C13—C9118.3 (2)N6—C20—H20B108.9
C14—C13—C16124.0 (2)C21—C20—H20B108.9
C9—C13—C16117.8 (2)H20A—C20—H20B107.7
C13—C14—C15123.4 (2)C20—C21—H21A109.5
C13—C14—H14118.3C20—C21—H21B109.5
C15—C14—H14118.3H21A—C21—H21B109.5
O5—C15—O4117.0 (2)C20—C21—H21C109.5
O5—C15—C14126.2 (2)H21A—C21—H21C109.5
O4—C15—C14116.9 (2)H21B—C21—H21C109.5
C13—C16—S2116.99 (17)

Experimental details

Crystal data
Chemical formulaC15H16BrNO2S2
Mr386.32
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)7.8958 (2), 8.0536 (2), 25.2735 (8)
β (°) 97.909 (2)
V3)1591.84 (8)
Z4
Radiation typeMo Kα
µ (mm1)2.85
Crystal size (mm)0.24 × 0.20 × 0.12
Data collection
DiffractometerBruker SMART CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2007)
Tmin, Tmax0.770, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
12640, 2806, 2419
Rint0.033
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.074, 1.04
No. of reflections2806
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.62, 0.44

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL2014/7 (Sheldrick, 2015), ORTEP-3 for Windows (Farrugia, 2012), SHELXL2014/7.

 

Acknowledgements

The authors thank to Universities Sophisticated Instrumental Centre, Karnatak University, Dharwad for CCD X-ray facilities, X-ray data collection.

References

First citationBruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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