organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

4-Bromo­methyl-6-meth­­oxy-2H-chromen-2-one

aDepartment of Physics, Govt. College for Women, Kolar 563 101, Karnataka, India, bDepartment of Chemistry, Karnatak University, Dharwad 580 003, Karnataka, India, and cDepartment of Physics, Govt. First Grade College, K.R. Pura, Bangalore 560 036, Karnataka, India
*Correspondence e-mail: rkgowdaphy@gmail.com

(Received 8 September 2010; accepted 16 October 2010; online 23 October 2010)

The structure of the title coumarin derivative, C11H9BrO3, is stabilized by weak inter­molecular C—H⋯O hydrogen bonds.

Related literature

For the properties of coumarins, see: Kulkarni et al. (2006[Kulkarni, M. V., Kulkarni, G. M., Lin, C.-H. & Sun, C.-M. (2006). Curr. Med. Chem. 13, 2795-2818.]); Fylaktakidou et al. (2004[Fylaktakidou, K. C., Hadjipavlou-Litina, D. J., Litinas, K. E. & Nicolaides, D. N. (2004). Curr. Pharm. Des. 10, 3813-3833.]); Neyts et al. (2009[Neyts, J., De Clercq, E., Singha, R., Chang, Y. H., Das, A. R., Chakraborty, S. K., Hong, S. C., Tsay, S.-C., Hsu, M.-H. & Hwu, J. R. (2009). J. Med. Chem. 52, 1486-1490.]); Kempen et al. (2003[Kempen, I., Papapostolou, D., Thierry, N., Pochet, L., Counerotte, S., Masereel, B., Foidart, J.-M., Reboud-Ravaux, M., Noel, A. & Pirotte, B. (2003). Br. J. Cancer, 88, 1111-1118.]). For structural analysis of coumarins, see: Gnanaguru et al. (1985[Gnanaguru, K., Ramasubbu, N., Venkatesan, K. & Ramamurthy, V. (1985). J. Org. Chem. 50, 2337-2346.]); Munshi & Guru Row (2005[Munshi, P. & Guru Row, T. N. (2005). J. Phys. Chem. A, 109, 659-672.]); Gavuzzo et al. (1974[Gavuzzo, E., Mazza, F. & Giglio, E. (1974). Acta Cryst. B30, 1351-1357.]); Moorthy et al. (2003[Moorthy, J. N., Venkatakrishnan, P. & Singh, A. (2003). CrystEngComm, 5, 507-513.]); Katerinopoulos (2004[Katerinopoulos, H. E. (2004). Curr. Pharm. Des. 10, 3835-3852.]). For Br-containing coumarins, see: Gaultier & Hauw (1965[Gaultier, J. & Hauw, C. (1965). Acta Cryst. 19, 927-933.]); Kokila et al. (1996[Kokila, M. K., Puttaraja,, Kulkarni, M. V. & Shivaprakash, N. C. (1996). Acta Cryst. C52, 2078-2081.]); Vasudevan et al. (1991[Vasudevan, K. T., Puttaraja, & Kulkarni, M. V. (1991). Acta Cryst. C47, 775-777.]).

[Scheme 1]

Experimental

Crystal data
  • C11H9BrO3

  • Mr = 269.09

  • Monoclinic, P 21 /n

  • a = 4.3573 (3) Å

  • b = 9.2859 (6) Å

  • c = 25.2677 (17) Å

  • β = 91.927 (3)°

  • V = 1021.79 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.01 mm−1

  • T = 293 K

  • 0.25 × 0.15 × 0.1 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.434, Tmax = 0.501

  • 9950 measured reflections

  • 2128 independent reflections

  • 1501 reflections with I > 2σ(I)

  • Rint = 0.037

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.101

  • S = 0.96

  • 2128 reflections

  • 137 parameters

  • H-atom parameters constrained

  • Δρmax = 0.93 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2⋯O1i 0.93 2.60 3.451 (4) 152
C2—H2⋯O2i 0.93 2.58 3.446 (5) 155
C10—H10A⋯O2i 0.97 2.57 3.437 (5) 148
C8—H8⋯O2ii 0.93 2.56 3.433 (5) 156
C10—H10A⋯O1iii 0.97 2.98 3.601 (4) 122
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Coumarins are a class of naturally occurring oxygen heterocycles which have been found to exhibit wide ranging biological activities (Kulkarni et al., 2006; Fylaktakidou et al., 2004; Neyts et al., 2009) through its innumerable derivatives. Structural studies on coumarins have been focused on their solid state photochemical dimerization (Gnanaguru et al., 1985), hydrogen bonding (Munshi et al., 2005), mode of packing (Gavuzzo et al., 1974), molecular self assembling (Moorthy et al., 2003) and photophysical properties (Katerinopoulos et al., 2004). Introduction of bromine has resulted in formation of hydrates, intermolecular hydrogen bonds, and eclipsed conformation, as observed in 3-bromocoumarin (Gaultier et al., 1965), 6-bromo-3-acetylcoumarin (Kokila et al., 1996), and 3-bromoacetylcoumarin (Vasudevan et al., 1991), respectively. 3-Bromophenyl-6-acetoxymethyl-coumarin-3-carboxylates have been found to exhibit potential anticancer and antitumour activity (Kempen et al., 2003).

The title compound is cyclic, planar and aromatic in nature due to the continuous delocalization of electrons over the coumarin rings system. There is a significant deviation from trigonality in bond angle at O1—C1—C2 [117.0 (3)°], due to the electronic repulsion of atom O2 which is bonded to C1. This is also reflected at C9—C4—C5 [117.9 (3)°] and C9—C4—C3 [117.6 (3)°] but these are due to fused benzene and α pyrone rings. Another significant deviation in bond angle is observed at C6—O3—C11 [118.0 (3)°] due to the repulsion between lone pair electrons of atom O3 with valence electrons of C6—O3 and O3—C11 bonds.

Related literature top

For the properties of coumarins, see: Kulkarni et al. (2006); Fylaktakidou et al. (2004); Neyts et al. (2009); Kempen et al. (2003). For structural analysis of coumarins, see: Gnanaguru et al. (1985); Munshi & Guru Row (2005); Gavuzzo et al. (1974); Moorthy et al. (2003); Katerinopoulos (2004). For Br-containing coumarins, see: Gaultier & Hauw (1965); Kokila et al. (1996); Vasudevan et al. (1991).

Experimental top

To a mixture of equimolar quantity of 4-methoxy phenol (0.1 mol) and 4-bromoethylacetoacetate (0.1 mol) was added drop wise sulfuric acid (30 ml) with stirring and maintaining the temperature between 0-5 °C. The reaction mixture was allowed to stand in ice chest overnight and deep red coloured solution was poured into the stream of crushed ice. Solid separated was filtered and washed with water and then with cold ethanol so as to get a colourless compound. Finally, it is recrystallized from acetic acid.

Refinement top

All the H atoms were positioned geometrically and refined using a riding model with bond lengths 0.97 (methylene), 0.96 (methyl) or 0.93 Å (aromatic). Isotropic displacement parameters were calculated as Uĩso~(H) = 1.5U~eq~(C) for methyl group C11 and Uĩso~(H) = 1.2U~eq~(C) for all other H atoms.

Structure description top

Coumarins are a class of naturally occurring oxygen heterocycles which have been found to exhibit wide ranging biological activities (Kulkarni et al., 2006; Fylaktakidou et al., 2004; Neyts et al., 2009) through its innumerable derivatives. Structural studies on coumarins have been focused on their solid state photochemical dimerization (Gnanaguru et al., 1985), hydrogen bonding (Munshi et al., 2005), mode of packing (Gavuzzo et al., 1974), molecular self assembling (Moorthy et al., 2003) and photophysical properties (Katerinopoulos et al., 2004). Introduction of bromine has resulted in formation of hydrates, intermolecular hydrogen bonds, and eclipsed conformation, as observed in 3-bromocoumarin (Gaultier et al., 1965), 6-bromo-3-acetylcoumarin (Kokila et al., 1996), and 3-bromoacetylcoumarin (Vasudevan et al., 1991), respectively. 3-Bromophenyl-6-acetoxymethyl-coumarin-3-carboxylates have been found to exhibit potential anticancer and antitumour activity (Kempen et al., 2003).

The title compound is cyclic, planar and aromatic in nature due to the continuous delocalization of electrons over the coumarin rings system. There is a significant deviation from trigonality in bond angle at O1—C1—C2 [117.0 (3)°], due to the electronic repulsion of atom O2 which is bonded to C1. This is also reflected at C9—C4—C5 [117.9 (3)°] and C9—C4—C3 [117.6 (3)°] but these are due to fused benzene and α pyrone rings. Another significant deviation in bond angle is observed at C6—O3—C11 [118.0 (3)°] due to the repulsion between lone pair electrons of atom O3 with valence electrons of C6—O3 and O3—C11 bonds.

For the properties of coumarins, see: Kulkarni et al. (2006); Fylaktakidou et al. (2004); Neyts et al. (2009); Kempen et al. (2003). For structural analysis of coumarins, see: Gnanaguru et al. (1985); Munshi & Guru Row (2005); Gavuzzo et al. (1974); Moorthy et al. (2003); Katerinopoulos (2004). For Br-containing coumarins, see: Gaultier & Hauw (1965); Kokila et al. (1996); Vasudevan et al. (1991).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEP diagram of the title molecule with 50% probability displacement ellipsoids for non-H atoms.
4-Bromomethyl-6-methoxy-2H-chromen-2-one top
Crystal data top
C11H9BrO3F(000) = 536
Mr = 269.09Dx = 1.749 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3217 reflections
a = 4.3573 (3) Åθ = 2.3–25.4°
b = 9.2859 (6) ŵ = 4.01 mm1
c = 25.2677 (17) ÅT = 293 K
β = 91.927 (3)°Needle, colourless
V = 1021.79 (12) Å30.25 × 0.15 × 0.1 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2128 independent reflections
Radiation source: fine-focus sealed tube1501 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ω and φ scansθmax = 26.6°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 53
Tmin = 0.434, Tmax = 0.501k = 1111
9950 measured reflectionsl = 3131
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H-atom parameters constrained
S = 0.96 w = 1/[σ2(Fo2) + (0.0467P)2 + 1.203P]
where P = (Fo2 + 2Fc2)/3
2128 reflections(Δ/σ)max = 0.008
137 parametersΔρmax = 0.93 e Å3
0 restraintsΔρmin = 0.26 e Å3
0 constraints
Crystal data top
C11H9BrO3V = 1021.79 (12) Å3
Mr = 269.09Z = 4
Monoclinic, P21/nMo Kα radiation
a = 4.3573 (3) ŵ = 4.01 mm1
b = 9.2859 (6) ÅT = 293 K
c = 25.2677 (17) Å0.25 × 0.15 × 0.1 mm
β = 91.927 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2128 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
1501 reflections with I > 2σ(I)
Tmin = 0.434, Tmax = 0.501Rint = 0.037
9950 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.101H-atom parameters constrained
S = 0.96Δρmax = 0.93 e Å3
2128 reflectionsΔρmin = 0.26 e Å3
137 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.3658 (8)0.2636 (4)0.73840 (14)0.0406 (9)
C20.4641 (8)0.1339 (4)0.71330 (13)0.0375 (8)
H20.39440.04620.72600.045*
C30.6518 (7)0.1332 (4)0.67239 (13)0.0321 (7)
C40.7577 (7)0.2706 (4)0.65171 (12)0.0318 (7)
C50.9489 (7)0.2851 (4)0.60828 (13)0.0348 (8)
H51.01390.20350.59050.042*
C61.0401 (7)0.4188 (4)0.59198 (13)0.0378 (9)
C70.9456 (8)0.5407 (4)0.61872 (14)0.0429 (9)
H71.01210.63110.60810.051*
C80.7556 (8)0.5293 (4)0.66048 (14)0.0401 (9)
H80.68890.61130.67780.048*
C90.6642 (7)0.3941 (4)0.67652 (13)0.0345 (8)
C100.7530 (9)0.0074 (4)0.65024 (14)0.0421 (9)
H10A0.70860.08370.67510.050*
H10B0.97330.00520.64600.050*
C111.2815 (9)0.3270 (5)0.51587 (15)0.0535 (11)
H11A1.40050.25540.53470.080*
H11B1.39390.36120.48630.080*
H11C1.09080.28560.50330.080*
O10.4744 (5)0.3905 (3)0.71899 (9)0.0397 (6)
O20.1939 (7)0.2719 (3)0.77495 (11)0.0569 (7)
O31.2213 (6)0.4438 (3)0.55030 (10)0.0500 (7)
Br10.54925 (10)0.04981 (5)0.582134 (17)0.0612 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0437 (19)0.039 (2)0.039 (2)0.0003 (18)0.0059 (16)0.0004 (17)
C20.0442 (19)0.029 (2)0.0390 (19)0.0025 (16)0.0024 (16)0.0004 (16)
C30.0345 (17)0.027 (2)0.0344 (18)0.0024 (15)0.0010 (14)0.0003 (14)
C40.0310 (16)0.034 (2)0.0301 (17)0.0032 (15)0.0022 (13)0.0012 (15)
C50.0338 (17)0.036 (2)0.0350 (18)0.0037 (16)0.0031 (14)0.0014 (16)
C60.0371 (18)0.042 (2)0.0343 (19)0.0030 (16)0.0050 (15)0.0044 (15)
C70.051 (2)0.030 (2)0.048 (2)0.0055 (18)0.0027 (17)0.0076 (17)
C80.050 (2)0.029 (2)0.042 (2)0.0018 (17)0.0008 (16)0.0045 (16)
C90.0335 (17)0.037 (2)0.0333 (18)0.0008 (15)0.0020 (14)0.0007 (15)
C100.048 (2)0.032 (2)0.046 (2)0.0050 (17)0.0039 (17)0.0013 (17)
C110.063 (3)0.053 (3)0.045 (2)0.000 (2)0.0162 (19)0.002 (2)
O10.0483 (14)0.0339 (15)0.0376 (13)0.0013 (12)0.0117 (11)0.0024 (11)
O20.0759 (19)0.0461 (18)0.0508 (16)0.0039 (15)0.0305 (15)0.0005 (13)
O30.0618 (16)0.0435 (17)0.0460 (15)0.0072 (13)0.0208 (13)0.0030 (13)
Br10.0732 (3)0.0518 (3)0.0587 (3)0.0043 (2)0.0017 (2)0.0214 (2)
Geometric parameters (Å, º) top
C1—O21.211 (4)C7—C81.367 (5)
C1—O11.367 (4)C7—H70.9300
C1—C21.434 (5)C8—C91.382 (5)
C2—C31.340 (5)C8—H80.9300
C2—H20.9300C9—O11.377 (4)
C3—C41.459 (5)C10—Br11.950 (4)
C3—C101.493 (5)C10—H10A0.9700
C4—C91.375 (5)C10—H10B0.9700
C4—C51.406 (5)C11—O31.420 (5)
C5—C61.371 (5)C11—H11A0.9600
C5—H50.9300C11—H11B0.9600
C6—O31.357 (4)C11—H11C0.9600
C6—C71.388 (5)
O2—C1—O1116.7 (3)C7—C8—C9119.0 (3)
O2—C1—C2126.3 (4)C7—C8—H8120.5
O1—C1—C2117.0 (3)C9—C8—H8120.5
C3—C2—C1123.0 (3)C4—C9—C8122.1 (3)
C3—C2—H2118.5C4—C9—O1122.0 (3)
C1—C2—H2118.5C8—C9—O1115.9 (3)
C2—C3—C4118.7 (3)C3—C10—Br1112.1 (2)
C2—C3—C10119.3 (3)C3—C10—H10A109.2
C4—C3—C10122.0 (3)Br1—C10—H10A109.2
C9—C4—C5117.9 (3)C3—C10—H10B109.2
C9—C4—C3117.6 (3)Br1—C10—H10B109.2
C5—C4—C3124.5 (3)H10A—C10—H10B107.9
C6—C5—C4120.4 (3)O3—C11—H11A109.5
C6—C5—H5119.8O3—C11—H11B109.5
C4—C5—H5119.8H11A—C11—H11B109.5
O3—C6—C5124.7 (3)O3—C11—H11C109.5
O3—C6—C7115.4 (3)H11A—C11—H11C109.5
C5—C6—C7119.9 (3)H11B—C11—H11C109.5
C8—C7—C6120.7 (3)C1—O1—C9121.6 (3)
C8—C7—H7119.7C6—O3—C11118.0 (3)
C6—C7—H7119.7
O2—C1—C2—C3179.0 (3)C5—C4—C9—C80.9 (5)
O1—C1—C2—C30.5 (5)C3—C4—C9—C8179.0 (3)
C1—C2—C3—C41.0 (5)C5—C4—C9—O1179.3 (3)
C1—C2—C3—C10177.4 (3)C3—C4—C9—O10.8 (4)
C2—C3—C4—C91.6 (4)C7—C8—C9—C40.2 (5)
C10—C3—C4—C9176.7 (3)C7—C8—C9—O1179.6 (3)
C2—C3—C4—C5178.5 (3)C2—C3—C10—Br1106.3 (3)
C10—C3—C4—C53.2 (5)C4—C3—C10—Br175.4 (3)
C9—C4—C5—C60.7 (5)O2—C1—O1—C9178.1 (3)
C3—C4—C5—C6179.2 (3)C2—C1—O1—C91.4 (5)
C4—C5—C6—O3179.3 (3)C4—C9—O1—C10.8 (5)
C4—C5—C6—C70.5 (5)C8—C9—O1—C1179.4 (3)
O3—C6—C7—C8178.2 (3)C5—C6—O3—C1110.6 (5)
C5—C6—C7—C81.6 (5)C7—C6—O3—C11169.2 (3)
C6—C7—C8—C91.4 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.603.451 (4)152
C2—H2···O2i0.932.583.446 (5)155
C10—H10A···O2i0.972.573.437 (5)148
C8—H8···O2ii0.932.563.433 (5)156
C10—H10A···O1iii0.972.983.601 (4)122
Symmetry codes: (i) x+1/2, y1/2, z+3/2; (ii) x+1/2, y+1/2, z+3/2; (iii) x+3/2, y1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC11H9BrO3
Mr269.09
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)4.3573 (3), 9.2859 (6), 25.2677 (17)
β (°) 91.927 (3)
V3)1021.79 (12)
Z4
Radiation typeMo Kα
µ (mm1)4.01
Crystal size (mm)0.25 × 0.15 × 0.1
Data collection
DiffractometerBruker Kappa APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.434, 0.501
No. of measured, independent and
observed [I > 2σ(I)] reflections
9950, 2128, 1501
Rint0.037
(sin θ/λ)max1)0.630
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.101, 0.96
No. of reflections2128
No. of parameters137
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.93, 0.26

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT (Bruker, 2004), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.932.603.451 (4)152
C2—H2···O2i0.932.583.446 (5)155
C10—H10A···O2i0.972.573.437 (5)148
C8—H8···O2ii0.932.563.433 (5)156
C10—H10A···O1iii0.972.983.601 (4)122
Symmetry codes: (i) x+1/2, y1/2, z+3/2; (ii) x+1/2, y+1/2, z+3/2; (iii) x+3/2, y1/2, z+3/2.
 

Footnotes

Alternative affiliation: MVJ College of Engineering, Bangalore 560 067, India.

Acknowledgements

RG thanks the MVJ College of Engineering, Bangalore-67 (VTU Research Center) for providing research facilities. The authors also thank the SAIF, IIT-Madras, Channai, for the data collection.

References

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