3,5-Dibromo-2′,3′,4′,5′,6′-penta­methyl-1,1′-biphen­yl

Roşca, S.; Olaru, M.; Raţ, C.I.; Silvestru, C.

doi:10.1107/S1600536810015308

organic compounds

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ISSN: 2056-9890

Volume 66| Part 6| June 2010| Page o1248

https://doi.org/10.1107/S1600536810015308

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3,5-Dibromo-2′,3′,4′,5′,6′-pentamethyl-1,1′-biphenyl

Sorin Roşca,^a Marian Olaru,^a Ciprian I. Raţ ^a ^* and Cristian Silvestru ^a

^aUniversitatea Babeş-Bolyai, Facultatea de Chimie şi Inginerie Chimicã, 11 Arany Janos, 400028 Cluj-Napoca, Romania
^*Correspondence e-mail: crat@chem.ubbcluj.ro

(Received 12 April 2010; accepted 26 April 2010; online 8 May 2010)

In the crystal structure of the title compound, C₁₇H₁₈Br₂, the benzene rings are almost perpendicular [dihedral angle = 84.0 (3)°]. The crystal structure is consolidated by the presence of C—Br⋯π interactions.

Related literature

For structures of related methyl substituted biphenyls, see: Fröhlich & Musso (1985 ); Hafelinger & Strähle (1976 ); Hartmann & Niemeyer (2001 ); Niemeyer (2006 ); Pickett (1936 ); Rathore et al. (1997 ). For background to ligands containing m-terphenyl groups, see: Berthiol et al. (2004 ); Cocchi et al. (2007 ); Collins et al. (2002 ); Du et al. (1986 ); Kim et al. (2005 ); Konishi et al. (2006 ); Matsumoto et al. (2004 ); Power (2004 ).

Experimental

Crystal data

C₁₇H₁₈Br₂
M_r = 382.13
Monoclinic, P 2₁ /n
a = 9.011 (5) Å
b = 14.065 (8) Å
c = 12.387 (7) Å
β = 94.613 (9)°
V = 1564.8 (15) Å³
Z = 4
Mo Kα radiation
μ = 5.17 mm⁻¹
T = 297 K
0.35 × 0.32 × 0.29 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.265, T_max = 0.316
10702 measured reflections
2760 independent reflections
1588 reflections with I > 2σ(I)
R_int = 0.127

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.150
S = 0.94
2760 reflections
178 parameters
H-atom parameters constrained
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.53 e Å⁻³

Table 1
C–Br⋯π interactions (Å, °)

Cg2 is the centroid of the C7–C12 benzene ring.

Y—X⋯Cg	Y—X	X⋯Cg	Y⋯Cg	Y—X⋯Cg
C1—Br1⋯Cg2ⁱ	1.883 (6)	3.464 (3)	5.283 (8)	161.4 (2)
Symmetry code: (i) 1 + x, y, z.

Data collection: SMART (Bruker, 2000); cell refinement: SAINT-Plus (Bruker, 2001 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009 ); software used to prepare material for publication: publCIF (Westrip, 2010 ) and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810015308/pk2243sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810015308/pk2243Isup2.hkl

checkCIF report

Comment top

Ligands containing m-terphenyl groups are known to stabilize many classes of compounds (Power, 2004).

The m-terphenyl organic precursors are prepared by coupling, via a two aryne sequence, between aromatic halides and two equivalents of Grignard reagent (Du et al., 1986) or by palladium catalyzed cross-coupling reactions (Collins et al., 2002; Matsumoto et al., 2004; Berthiol et al., 2004; Kim et al., 2005; Konishi et al., 2006; Cocchi et al., 2007).

The title compound was obtained as a side-product in the preparation of 3,5-(2,3,4,5,6-Me₅C₆)₂C₆H₃Br by the Suzuki cross-coupling between 2,3,4,5,6-Me₅C₆B(OH)₂ and 1,3,5-Br₃C₆H₃.

The dihedral angle between the planes containing the two benzene rings is 84.0 (3)° (Fig. 1), similar to those observed for the closest related compounds 2,3,4,5,6,4'-hexamethylbiphenyl tetrachloro-p-benzoquinone adduct (Rathore et al., 1997) or 2-iodo-2',3',4',5',6'-pentamethylbiphenyl (Hartmann & Niemeyer, 2001). The bond lengths and bonding angles are normal.

In the crystal structure there are intermolecular interactions between the bromine atoms and the π electrons the methyl substituted benzene rings (Fig. 2 and Table 1).

Related literature top

For structures of related methyl substituted biphenyls, see: Fröhlich & Musso (1985); Hafelinger & Strähle (1976); Hartmann & Niemeyer (2001); Niemeyer (2006); Pickett (1936); Rathore et al. (1997). For background to ligands containing m-terphenyl groups, see: Berthiol et al. (2004); Cocchi et al. (2007); Collins et al. (2002); Du et al. (1986); Kim et al. (2005); Konishi et al. (2006); Matsumoto et al. (2004); Power (2004).

Experimental top

Colourless crystals were obtained by slow evaporation of the solvents from solutions of the title compound in a mixture of dichloromethane and hexane. mp = 177–178 °C. ¹H NMR (300 MHz, CDCl₃): δ 1.95 (s, 6H), 2.25 (s, 6H), 2.30 (s, 3H), 7.24 (d, J = 1.8 Hz, 2H), 7.66 (t, J = 1.8 Hz, 1H). ¹³C NMR (75 MHz, CDCl₃): δ 16.71, 16.98, 18.56, 123.00, 131.32, 131.58, 132.15, 132.76, 135.02, 137.14, 146.98.

Structure description top

Ligands containing m-terphenyl groups are known to stabilize many classes of compounds (Power, 2004).

In the crystal structure there are intermolecular interactions between the bromine atoms and the π electrons the methyl substituted benzene rings (Fig. 2 and Table 1).

For structures of related methyl substituted biphenyls, see: Fröhlich & Musso (1985); Hafelinger & Strähle (1976); Hartmann & Niemeyer (2001); Niemeyer (2006); Pickett (1936); Rathore et al. (1997). For background to ligands containing m-terphenyl groups, see: Berthiol et al. (2004); Cocchi et al. (2007); Collins et al. (2002); Du et al. (1986); Kim et al. (2005); Konishi et al. (2006); Matsumoto et al. (2004); Power (2004).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Figures top

	Fig. 1. Crystal structure of the title compound with labelling and displacement ellipsoids of Br and C atoms drawn at 25 % probability level.
	Fig. 2. Intermolecular Br···π interactions (shown as dashed lines) in the structure of the title compound. Cg2 is the centroid of the benzene ring C7–C12. Symmetry codes: (i) 1+x, y, z; (ii) -1+x, y, z.

3,5-Dibromo-2',3',4',5',6'-pentamethyl-1,1'-biphenyl top

Crystal data top

C₁₇H₁₈Br₂	F(000) = 760
M_r = 382.13	D_x = 1.622 Mg m⁻³
Monoclinic, P2₁/n	Melting point = 451–450 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 9.011 (5) Å	Cell parameters from 2189 reflections
b = 14.065 (8) Å	θ = 2.7–22.4°
c = 12.387 (7) Å	µ = 5.17 mm⁻¹
β = 94.613 (9)°	T = 297 K
V = 1564.8 (15) Å³	Blocks, colourless
Z = 4	0.35 × 0.32 × 0.29 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2760 independent reflections
Radiation source: fine-focus sealed tube	1588 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.127
φ and ω scans	θ_max = 25.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −10→10
T_min = 0.265, T_max = 0.316	k = −16→16
10702 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.057	H-atom parameters constrained
wR(F²) = 0.150	w = 1/[σ²(F_o²) + (0.0001P)²] where P = (F_o² + 2F_c²)/3
S = 0.94	(Δ/σ)_max = 0.001
2760 reflections	Δρ_max = 0.67 e Å⁻³
178 parameters	Δρ_min = −0.53 e Å⁻³
0 restraints	Extinction correction: (SHELXL97; Sheldrick, 2008)
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0150 (15)

Crystal data top

C₁₇H₁₈Br₂	V = 1564.8 (15) Å³
M_r = 382.13	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.011 (5) Å	µ = 5.17 mm⁻¹
b = 14.065 (8) Å	T = 297 K
c = 12.387 (7) Å	0.35 × 0.32 × 0.29 mm
β = 94.613 (9)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2760 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1588 reflections with I > 2σ(I)
T_min = 0.265, T_max = 0.316	R_int = 0.127
10702 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	0 restraints
wR(F²) = 0.150	H-atom parameters constrained
S = 0.94	Δρ_max = 0.67 e Å⁻³
2760 reflections	Δρ_min = −0.53 e Å⁻³
178 parameters

Special details top

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.

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
Br1	1.08347 (7)	0.76924 (6)	0.65316 (7)	0.0714 (4)
Br2	0.65525 (8)	1.06226 (5)	0.62304 (8)	0.0736 (4)
C1	0.8834 (7)	0.8091 (5)	0.6463 (5)	0.0440 (16)
C2	0.8516 (6)	0.9036 (5)	0.6407 (5)	0.0498 (17)
H2	0.9275	0.9485	0.6415	0.06*
C3	0.7030 (7)	0.9318 (4)	0.6337 (5)	0.0473 (16)
C4	0.5917 (6)	0.8654 (4)	0.6332 (4)	0.0376 (15)
H4	0.4928	0.885	0.6279	0.045*
C5	0.6246 (6)	0.7700 (4)	0.6404 (5)	0.0392 (15)
C6	0.7720 (6)	0.7427 (4)	0.6455 (5)	0.0428 (15)
H6	0.7962	0.6784	0.6483	0.051*
C7	0.5039 (6)	0.6982 (4)	0.6411 (5)	0.0394 (15)
C8	0.4465 (6)	0.6539 (4)	0.5448 (5)	0.0445 (16)
C9	0.3389 (6)	0.5839 (4)	0.5454 (6)	0.0468 (17)
C10	0.2872 (7)	0.5553 (5)	0.6454 (7)	0.0544 (18)
C11	0.3451 (7)	0.5992 (5)	0.7412 (6)	0.0484 (17)
C12	0.4511 (6)	0.6700 (4)	0.7391 (5)	0.0444 (16)
C13	0.5038 (7)	0.6859 (5)	0.4388 (5)	0.0609 (19)
H13A	0.5304	0.6312	0.3981	0.091*
H13B	0.5898	0.7255	0.4535	0.091*
H13C	0.4276	0.7211	0.3976	0.091*
C14	0.2779 (8)	0.5413 (5)	0.4401 (6)	0.067 (2)
H14A	0.2468	0.5912	0.3904	0.101*
H14B	0.1942	0.5016	0.4522	0.101*
H14C	0.3536	0.5039	0.4101	0.101*
C15	0.1694 (8)	0.4811 (6)	0.6491 (8)	0.086 (3)
H15A	0.1919	0.4406	0.7106	0.129*
H15B	0.1659	0.4437	0.584	0.129*
H15C	0.0747	0.5111	0.6549	0.129*
C16	0.2841 (9)	0.5705 (6)	0.8452 (7)	0.084 (3)
H16A	0.3278	0.6092	0.9031	0.126*
H16B	0.3073	0.5049	0.8599	0.126*
H16C	0.178	0.5789	0.8392	0.126*
C17	0.5056 (8)	0.7204 (5)	0.8418 (6)	0.065 (2)
H17A	0.4264	0.7581	0.8668	0.097*
H17B	0.5877	0.7609	0.8279	0.097*
H17C	0.5374	0.6744	0.896	0.097*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0413 (5)	0.1017 (7)	0.0722 (6)	0.0182 (4)	0.0113 (4)	−0.0009 (5)
Br2	0.0704 (6)	0.0468 (5)	0.1041 (8)	0.0015 (4)	0.0105 (5)	−0.0050 (4)
C1	0.041 (3)	0.054 (4)	0.038 (4)	0.012 (3)	0.011 (3)	−0.001 (3)
C2	0.037 (4)	0.073 (5)	0.042 (4)	−0.011 (3)	0.016 (3)	−0.005 (4)
C3	0.042 (4)	0.053 (4)	0.048 (4)	0.001 (3)	0.009 (3)	−0.005 (3)
C4	0.035 (3)	0.046 (4)	0.032 (4)	0.007 (3)	0.008 (3)	0.000 (3)
C5	0.040 (3)	0.049 (4)	0.030 (3)	0.001 (3)	0.011 (3)	0.000 (3)
C6	0.044 (4)	0.045 (4)	0.040 (4)	0.011 (3)	0.006 (3)	−0.002 (3)
C7	0.040 (3)	0.040 (3)	0.039 (4)	0.003 (3)	0.009 (3)	−0.002 (3)
C8	0.044 (4)	0.048 (4)	0.041 (4)	0.009 (3)	0.006 (3)	−0.002 (3)
C9	0.030 (3)	0.051 (4)	0.059 (5)	0.006 (3)	0.002 (3)	−0.006 (3)
C10	0.043 (4)	0.050 (4)	0.072 (6)	0.007 (3)	0.013 (4)	0.012 (4)
C11	0.042 (4)	0.056 (4)	0.050 (5)	0.015 (3)	0.022 (3)	0.008 (4)
C12	0.038 (3)	0.054 (4)	0.043 (4)	0.006 (3)	0.011 (3)	−0.004 (3)
C13	0.070 (5)	0.068 (5)	0.046 (5)	−0.005 (4)	0.016 (4)	−0.002 (4)
C14	0.061 (4)	0.071 (5)	0.068 (6)	−0.006 (4)	−0.001 (4)	−0.020 (4)
C15	0.060 (5)	0.088 (6)	0.113 (8)	−0.023 (4)	0.024 (5)	0.012 (5)
C16	0.067 (5)	0.110 (7)	0.080 (6)	−0.005 (5)	0.036 (5)	0.016 (5)
C17	0.077 (5)	0.071 (5)	0.048 (5)	0.006 (4)	0.019 (4)	−0.006 (4)

Geometric parameters (Å, º) top

Br1—C1	1.883 (6)	C10—C15	1.491 (9)
Br2—C3	1.887 (6)	C11—C12	1.381 (8)
C1—C2	1.361 (8)	C11—C16	1.496 (10)
C1—C6	1.370 (8)	C12—C17	1.504 (9)
C2—C3	1.392 (8)	C13—H13A	0.96
C2—H2	0.93	C13—H13B	0.96
C3—C4	1.370 (8)	C13—H13C	0.96
C4—C5	1.376 (8)	C14—H14A	0.96
C4—H4	0.93	C14—H14B	0.96
C5—C6	1.379 (7)	C14—H14C	0.96
C5—C7	1.484 (8)	C15—H15A	0.96
C6—H6	0.93	C15—H15B	0.96
C7—C12	1.397 (8)	C15—H15C	0.96
C7—C8	1.408 (8)	C16—H16A	0.96
C8—C9	1.382 (8)	C16—H16B	0.96
C8—C13	1.517 (9)	C16—H16C	0.96
C9—C10	1.417 (10)	C17—H17A	0.96
C9—C14	1.499 (9)	C17—H17B	0.96
C10—C11	1.401 (10)	C17—H17C	0.96

C2—C1—C6	121.0 (6)	C11—C12—C7	120.4 (6)
C2—C1—Br1	119.3 (5)	C11—C12—C17	120.2 (6)
C6—C1—Br1	119.7 (5)	C7—C12—C17	119.3 (6)
C1—C2—C3	118.6 (6)	C8—C13—H13A	109.5
C1—C2—H2	120.7	C8—C13—H13B	109.5
C3—C2—H2	120.7	H13A—C13—H13B	109.5
C4—C3—C2	120.4 (6)	C8—C13—H13C	109.5
C4—C3—Br2	120.0 (5)	H13A—C13—H13C	109.5
C2—C3—Br2	119.6 (5)	H13B—C13—H13C	109.5
C3—C4—C5	120.7 (6)	C9—C14—H14A	109.5
C3—C4—H4	119.6	C9—C14—H14B	109.5
C5—C4—H4	119.6	H14A—C14—H14B	109.5
C4—C5—C6	118.4 (6)	C9—C14—H14C	109.5
C4—C5—C7	120.6 (5)	H14A—C14—H14C	109.5
C6—C5—C7	121.0 (5)	H14B—C14—H14C	109.5
C1—C6—C5	120.9 (6)	C10—C15—H15A	109.5
C1—C6—H6	119.6	C10—C15—H15B	109.5
C5—C6—H6	119.6	H15A—C15—H15B	109.5
C12—C7—C8	118.9 (6)	C10—C15—H15C	109.5
C12—C7—C5	120.0 (6)	H15A—C15—H15C	109.5
C8—C7—C5	121.0 (6)	H15B—C15—H15C	109.5
C9—C8—C7	121.4 (6)	C11—C16—H16A	109.5
C9—C8—C13	120.2 (6)	C11—C16—H16B	109.5
C7—C8—C13	118.4 (6)	H16A—C16—H16B	109.5
C8—C9—C10	119.2 (6)	C11—C16—H16C	109.5
C8—C9—C14	119.2 (7)	H16A—C16—H16C	109.5
C10—C9—C14	121.6 (6)	H16B—C16—H16C	109.5
C11—C10—C9	119.3 (6)	C12—C17—H17A	109.5
C11—C10—C15	120.1 (7)	C12—C17—H17B	109.5
C9—C10—C15	120.7 (7)	H17A—C17—H17B	109.5
C12—C11—C10	120.9 (6)	C12—C17—H17C	109.5
C12—C11—C16	120.9 (7)	H17A—C17—H17C	109.5
C10—C11—C16	118.2 (7)	H17B—C17—H17C	109.5

C6—C1—C2—C3	−0.2 (9)	C7—C8—C9—C10	−1.0 (9)
Br1—C1—C2—C3	178.9 (5)	C13—C8—C9—C10	−180.0 (6)
C1—C2—C3—C4	0.4 (9)	C7—C8—C9—C14	177.9 (5)
C1—C2—C3—Br2	−178.8 (5)	C13—C8—C9—C14	−1.0 (9)
C2—C3—C4—C5	0.5 (9)	C8—C9—C10—C11	0.6 (9)
Br2—C3—C4—C5	179.7 (4)	C14—C9—C10—C11	−178.3 (6)
C3—C4—C5—C6	−1.6 (8)	C8—C9—C10—C15	179.0 (6)
C3—C4—C5—C7	179.3 (6)	C14—C9—C10—C15	0.1 (9)
C2—C1—C6—C5	−0.9 (9)	C9—C10—C11—C12	0.2 (9)
Br1—C1—C6—C5	−180.0 (4)	C15—C10—C11—C12	−178.2 (6)
C4—C5—C6—C1	1.8 (9)	C9—C10—C11—C16	177.5 (6)
C7—C5—C6—C1	−179.1 (6)	C15—C10—C11—C16	−0.9 (9)
C4—C5—C7—C12	−89.5 (7)	C10—C11—C12—C7	−0.8 (9)
C6—C5—C7—C12	91.4 (7)	C16—C11—C12—C7	−178.0 (6)
C4—C5—C7—C8	94.0 (7)	C10—C11—C12—C17	176.4 (6)
C6—C5—C7—C8	−85.0 (7)	C16—C11—C12—C17	−0.8 (9)
C12—C7—C8—C9	0.5 (9)	C8—C7—C12—C11	0.4 (9)
C5—C7—C8—C9	177.0 (5)	C5—C7—C12—C11	−176.1 (5)
C12—C7—C8—C13	179.5 (5)	C8—C7—C12—C17	−176.8 (5)
C5—C7—C8—C13	−4.0 (8)	C5—C7—C12—C17	6.7 (8)

Experimental details

Crystal data
Chemical formula	C₁₇H₁₈Br₂
M_r	382.13
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	297
a, b, c (Å)	9.011 (5), 14.065 (8), 12.387 (7)
β (°)	94.613 (9)
V (Å³)	1564.8 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	5.17
Crystal size (mm)	0.35 × 0.32 × 0.29

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.265, 0.316
No. of measured, independent and observed [I > 2σ(I)] reflections	10702, 2760, 1588
R_int	0.127
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.150, 0.94
No. of reflections	2760
No. of parameters	178
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.53

Computer programs: SMART (Bruker, 2000), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2009), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

C–Br···π interactions (Å, °) top

Cg2 is the centroid of the C7–C12 benzene ring.

Y—X···Cg	Y—X	X···Cg	Y···Cg	Y—X···Cg
C1—Br1···Cg2ⁱ	1.883 (6)	3.464 (3)	5.283 (8)	161.4 (2)

Symmetry code: (i) 1+x, y, z.

Acknowledgements

This work was supported by the National University Research Council (CNCSIS) of Romania (project RP 2/January 2008). SR thanks Babeş-Bolyai University for a research fellowship (21/2009). We thank Dr Richard A. Varga for the crystallographic measurements and data refinement.

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