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

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ISSN: 2056-9890

Di­methyl 6-iodo-2-methyl-1,2-di­hydro­quinoline-2,4-di­carboxyl­ate

aDepartment of Chemistry, Çankırı Karatekin University, TR-18100 Çankırı, Turkey, bUniversität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and cDepartment of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey
*Correspondence e-mail: merzifon@hacettepe.edu.tr

(Received 30 July 2013; accepted 21 August 2013; online 31 August 2013)

In the title compound, C14H14INO4, the di­hydro­pyridine ring adopts a twist conformation. In the crystal, pairs of N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into inversion R22(10) and R22(18) dimers, forming infinite double chains running along the c axis.

Related literature

For the conversion of 1,2-di­hydro­quinoline derivatives to the syntheses of quinolines, see: Dauphinee & Forrest (1978[Dauphinee, G. A. & Forrest, T. P. (1978). Can. J. Chem. 56, 632-634.]). For the conversion of 1,2-di­hydro­quinoline derivatives to the syntheses of 1,2,3,4-tetra­hydro­quinolines, see: Katritzky et al. (1996[Katritzky, A. R., Rachwal, S. & Rachwal, B. (1996). Tetrahedron, 52, 15031-15070.]). For literature methods for the preparation of 1,2-di­hydro­quinolines, see: Dauphinee & Forrest (1978[Dauphinee, G. A. & Forrest, T. P. (1978). Can. J. Chem. 56, 632-634.]); Durgadas et al. (2010[Durgadas, S., Chatare, V. K., Mukkanti, K. & Pal, S. (2010). Lett. Org. Chem. 7, 306-310.]); Gültekin & Frey (2012[Gültekin, Z. & Frey, W. (2012). Arkivoc, viii, 250-261.]); Makino et al. (2003[Makino, K., Hara, O., Takiguchi, Y., Katano, T., Asakawa, Y., Hatano, K. & Hamada, Y. (2003). Tetrahedron Lett. 44, 8925-8929.]); Yadav et al. (2007[Yadav, J. S., Reddy, B. V. S., Premalatha, K. & Murty, M. S. R. (2007). J. Mol. Catal. A, 271, 161-163.]); Waldmann et al. (2008[Waldmann, H., Karunakar, G. V. & Kumar, K. (2008). Org. Lett. 10, 2159-2162.]). For related structures, see: Gültekin et al. (2010[Gültekin, Z., Frey, W., Tercan, B. & Hökelek, T. (2010). Acta Cryst. E66, o2891-o2892.], 2011a[Gültekin, Z., Frey, W., Tercan, B. & Hökelek, T. (2011a). Acta Cryst. E67, o672-o673.],b[Gültekin, Z., Frey, W. & Hökelek, T. (2011b). Acta Cryst. E67, o576.], 2012a[Gültekin, Z., Bolte, M. & Hökelek, T. (2012a). Acta Cryst. E68, o606.],b[Gültekin, Z., Bolte, M. & Hökelek, T. (2012b). Acta Cryst. E68, o710-o711.]). For ring puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davies, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C14H14INO4

  • Mr = 387.16

  • Triclinic, [P \overline 1]

  • a = 7.7994 (14) Å

  • b = 10.2797 (8) Å

  • c = 10.8056 (8) Å

  • α = 116.862 (3)°

  • β = 103.956 (4)°

  • γ = 96.780 (4)°

  • V = 723.80 (16) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.22 mm−1

  • T = 100 K

  • 0.76 × 0.65 × 0.48 mm

Data collection
  • Bruker Kappa APEXII DUO diffractometer

  • Absorption correction: numerical (Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]) Tmin = 0.283, Tmax = 0.415

  • 43287 measured reflections

  • 7044 independent reflections

  • 6902 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.073

  • S = 1.24

  • 7044 reflections

  • 190 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.88 e Å−3

  • Δρmin = −1.54 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O3i 0.82 (2) 2.17 (2) 2.9795 (19) 169 (2)
C5—H5⋯O1 0.95 2.22 2.866 (2) 125
C12—H12C⋯O1ii 0.98 2.46 3.132 (2) 126
Symmetry codes: (i) -x+1, -y+2, -z+2; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

1,2-Dihydroquinoline derivatives are important for the preparation of pharmaceuticals and other biologically active compounds, and they are versatile intermediates in organic chemistry. They are converted to the syntheses of quinolines (Dauphinee & Forrest, 1978) and 1,2,3,4-tetrahydroquinolines (Katritzky et al., 1996). Several methods have been described for the syntheses of 1,2-dihydroquinolines (Durgadas et al., 2010; Makino et al., 2003; Yadav et al., 2007; Dauphinee & Forrest, 1978; Waldmann et al., 2008).

The structures of some 1,2-dihydroquinoline derivatives, C16H19NO4 (Gültekin et al., 2010), C14H15NO4 (Gültekin et al., 2011a), C17H21NO7 (Gültekin et al., 2011b), C16H17NO5 (Gültekin et al., 2012a) and C14H14BrNO4 (Gültekin et al., 2012b) have also been determined.

In the title compound (Fig. 1), the ring A (C1-C4/C9/C10/N1) is not planar, but adopting a twisted conformation with puckering parameters (Cremer & Pople, 1975) QT = 0.332 (1)Å, ϕ = 35.3 (3)° and θ = 66.0 (2)°. Ring A has a pseudo two-fold axis running through the midpoints of the N1—C1 and C3—C4 bonds.

In the crystal structure, intermolecular N—H···O and C—H···O hydrogen bonds (Table 1) link the molecules into centrosymmetric R22(10) and R22(18) dimers, respectively (Bernstein et al., 1995) (Fig. 2), to form infinite double chains running along the c-axis.

Related literature top

For the conversion of 1,2-dihydroquinoline derivatives to the syntheses of quinolines, see: Dauphinee & Forrest (1978). For the conversion of 1,2-dihydroquinoline derivatives to the syntheses of 1,2,3,4-tetrahydroquinolines, see: Katritzky et al. (1996). For literature methods for the preparation of 1,2-dihydroquinolines, see: Dauphinee & Forrest (1978); Durgadas et al. (2010); Gültekin & Frey (2012); Makino et al. (2003); Yadav et al. (2007); Waldmann et al. (2008). For related structures, see: Gültekin et al. (2010, 2011a,b, 2012a,b) For ring puckering parameters, see: Cremer & Pople (1975). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

The title compound was synthesized by the literature method (Gültekin & Frey, 2012; Waldmann et al., 2008). p-iodo aniline (100 mg, 1 eq) was dissolved in acetonitrile (1.5 ml), and then Bi(OTf)3 (5 mol%, 0.05 eq) and methyl pyruvate (2.2 eq) were added to the mixture. The mixture was heated by microwave irradiation for 7 h until the starting material was completely consumed as monitored by TLC. The resultant residue was directly purified by flash chromatography on silica (EtOAc:Cylohexane 1:2). Recrystallization over pentane and ethyl acetate (70:30) gave a yellow crystalline solid (yield: 34%), Rf 0.56 (2:1 Cyclohexane/EtOAc) m.p.: 393 K.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); 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, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bond is shown as dashed line.
[Figure 2] Fig. 2. A partial packing diagram. Hydrogen bonds are shown as dashed lines. Hydrogen atoms not involved in hydrogen bonding have been omitted for clarity.
Dimethyl 6-iodo-2-methyl-1,2-dihydroquinoline-2,4-dicarboxylate top
Crystal data top
C14H14INO4Z = 2
Mr = 387.16F(000) = 380
Triclinic, P1Dx = 1.776 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.7994 (14) ÅCell parameters from 6892 reflections
b = 10.2797 (8) Åθ = 2.3–36.5°
c = 10.8056 (8) ŵ = 2.22 mm1
α = 116.862 (3)°T = 100 K
β = 103.956 (4)°Block, yellow
γ = 96.780 (4)°0.76 × 0.65 × 0.48 mm
V = 723.80 (16) Å3
Data collection top
Bruker Kappa APEXII DUO
diffractometer
7044 independent reflections
Radiation source: fine-focus sealed tube6902 reflections with I > 2σ(I)
Triumph monochromatorRint = 0.032
ϕ and ω scansθmax = 36.5°, θmin = 2.3°
Absorption correction: numerical
(Blessing, 1995)
h = 1313
Tmin = 0.283, Tmax = 0.415k = 1717
43287 measured reflectionsl = 1818
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.073 w = 1/[σ2(Fo2) + (0.0263P)2 + 0.7072P]
where P = (Fo2 + 2Fc2)/3
S = 1.24(Δ/σ)max < 0.001
7044 reflectionsΔρmax = 1.88 e Å3
190 parametersΔρmin = 1.54 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0715 (18)
Crystal data top
C14H14INO4γ = 96.780 (4)°
Mr = 387.16V = 723.80 (16) Å3
Triclinic, P1Z = 2
a = 7.7994 (14) ÅMo Kα radiation
b = 10.2797 (8) ŵ = 2.22 mm1
c = 10.8056 (8) ÅT = 100 K
α = 116.862 (3)°0.76 × 0.65 × 0.48 mm
β = 103.956 (4)°
Data collection top
Bruker Kappa APEXII DUO
diffractometer
7044 independent reflections
Absorption correction: numerical
(Blessing, 1995)
6902 reflections with I > 2σ(I)
Tmin = 0.283, Tmax = 0.415Rint = 0.032
43287 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0271 restraint
wR(F2) = 0.073H atoms treated by a mixture of independent and constrained refinement
S = 1.24Δρmax = 1.88 e Å3
7044 reflectionsΔρmin = 1.54 e Å3
190 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 > 2sigma(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
xyzUiso*/Ueq
I10.017285 (15)0.670510 (12)0.215800 (11)0.02370 (4)
O10.28824 (19)0.31504 (13)0.37768 (13)0.0217 (2)
O20.34912 (17)0.25624 (12)0.55598 (13)0.01879 (18)
O30.69165 (15)0.92071 (11)0.93569 (13)0.01678 (17)
O40.78140 (13)0.71616 (12)0.92154 (12)0.01509 (16)
N10.32777 (15)0.77436 (13)0.85280 (12)0.01270 (17)
H10.335 (4)0.858 (2)0.920 (2)0.020 (6)*
C10.46679 (16)0.70426 (14)0.88944 (13)0.01127 (17)
C20.42693 (16)0.54604 (14)0.76450 (14)0.01201 (18)
H20.472 (3)0.475 (3)0.787 (3)0.013 (5)*
C30.33684 (16)0.50661 (14)0.62481 (14)0.01130 (17)
C40.26466 (16)0.61703 (14)0.59074 (14)0.01143 (17)
C50.19306 (18)0.59520 (15)0.44880 (15)0.01460 (19)
H50.19420.50600.36640.018*
C60.12035 (19)0.70379 (16)0.42832 (15)0.0157 (2)
C70.11561 (19)0.83472 (16)0.54662 (16)0.0165 (2)
H70.06360.90730.53100.020*
C80.18759 (18)0.85846 (15)0.68790 (15)0.0149 (2)
H80.18510.94810.76930.018*
C90.26382 (16)0.75191 (14)0.71195 (14)0.01145 (17)
C100.47035 (19)0.70673 (18)1.03339 (15)0.0169 (2)
H10A0.49660.81151.11210.025*
H10B0.56560.66071.05990.025*
H10C0.35110.64961.01990.025*
C110.65818 (16)0.79393 (14)0.91643 (13)0.01153 (17)
C120.96471 (18)0.78904 (19)0.94143 (18)0.0191 (2)
H12A1.04540.72340.94380.029*
H12B1.01100.88541.03430.029*
H12C0.96150.80760.85970.029*
C130.31983 (17)0.35216 (14)0.50561 (15)0.01327 (19)
C140.3488 (3)0.10914 (18)0.4461 (2)0.0252 (3)
H14A0.37100.04580.49100.038*
H14B0.44540.11930.40500.038*
H14C0.22970.06210.36740.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
I10.02815 (6)0.02630 (6)0.01695 (5)0.00288 (4)0.00133 (4)0.01504 (4)
O10.0310 (6)0.0176 (4)0.0144 (4)0.0086 (4)0.0071 (4)0.0059 (4)
O20.0239 (5)0.0128 (4)0.0208 (5)0.0062 (3)0.0069 (4)0.0093 (4)
O30.0174 (4)0.0108 (4)0.0201 (4)0.0024 (3)0.0085 (3)0.0053 (3)
O40.0096 (3)0.0185 (4)0.0204 (4)0.0040 (3)0.0045 (3)0.0124 (4)
N10.0118 (4)0.0151 (4)0.0112 (4)0.0057 (3)0.0040 (3)0.0060 (3)
C10.0095 (4)0.0137 (4)0.0106 (4)0.0023 (3)0.0028 (3)0.0065 (4)
C20.0111 (4)0.0128 (4)0.0128 (4)0.0024 (3)0.0030 (3)0.0076 (4)
C30.0104 (4)0.0116 (4)0.0119 (4)0.0021 (3)0.0031 (3)0.0063 (4)
C40.0106 (4)0.0121 (4)0.0117 (4)0.0024 (3)0.0028 (3)0.0066 (4)
C50.0158 (5)0.0150 (5)0.0125 (5)0.0025 (4)0.0028 (4)0.0078 (4)
C60.0162 (5)0.0177 (5)0.0149 (5)0.0033 (4)0.0025 (4)0.0109 (4)
C70.0163 (5)0.0184 (5)0.0186 (5)0.0068 (4)0.0048 (4)0.0123 (5)
C80.0149 (5)0.0159 (5)0.0163 (5)0.0071 (4)0.0056 (4)0.0090 (4)
C90.0097 (4)0.0134 (4)0.0119 (4)0.0033 (3)0.0036 (3)0.0068 (4)
C100.0163 (5)0.0237 (6)0.0134 (5)0.0042 (4)0.0055 (4)0.0114 (5)
C110.0108 (4)0.0129 (4)0.0098 (4)0.0025 (3)0.0035 (3)0.0049 (4)
C120.0099 (4)0.0269 (6)0.0230 (6)0.0032 (4)0.0048 (4)0.0149 (5)
C130.0123 (4)0.0122 (4)0.0143 (5)0.0025 (3)0.0039 (4)0.0062 (4)
C140.0297 (7)0.0140 (5)0.0318 (8)0.0092 (5)0.0120 (6)0.0095 (5)
Geometric parameters (Å, º) top
I1—C62.0908 (14)C4—C91.4154 (17)
N1—C11.4447 (17)C5—C61.3888 (19)
N1—C91.3812 (17)C5—H50.9500
N1—H10.821 (17)C6—C71.388 (2)
O1—C131.2059 (17)C7—C81.387 (2)
O2—C131.3412 (17)C7—H70.9500
O2—C141.439 (2)C8—C91.3989 (18)
O3—C111.2075 (16)C8—H80.9500
O4—C111.3273 (16)C10—H10A0.9800
O4—C121.4508 (17)C10—H10B0.9800
C1—C21.5028 (18)C10—H10C0.9800
C1—C101.5376 (18)C12—H12A0.9800
C1—C111.5444 (17)C12—H12B0.9800
C2—C31.3435 (18)C12—H12C0.9800
C2—H20.94 (2)C14—H14A0.9800
C3—C41.4728 (17)C14—H14B0.9800
C3—C131.4890 (18)C14—H14C0.9800
C4—C51.4002 (18)
C13—O2—C14114.26 (13)C7—C8—H8119.6
C11—O4—C12115.43 (11)C9—C8—H8119.6
C1—N1—H1115 (2)N1—C9—C4120.20 (11)
C9—N1—C1120.03 (10)N1—C9—C8119.93 (11)
C9—N1—H1116 (2)C8—C9—C4119.75 (11)
N1—C1—C2109.26 (10)C1—C10—H10A109.5
N1—C1—C10108.89 (10)C1—C10—H10B109.5
N1—C1—C11110.73 (10)C1—C10—H10C109.5
C2—C1—C10111.83 (11)H10A—C10—H10B109.5
C2—C1—C11108.91 (10)H10A—C10—H10C109.5
C10—C1—C11107.20 (10)H10B—C10—H10C109.5
C1—C2—H2117.7 (15)O3—C11—O4124.68 (12)
C3—C2—C1121.91 (11)O3—C11—C1123.96 (11)
C3—C2—H2120.4 (15)O4—C11—C1111.31 (11)
C2—C3—C4120.28 (11)O4—C12—H12A109.5
C2—C3—C13118.60 (11)O4—C12—H12B109.5
C4—C3—C13121.05 (11)O4—C12—H12C109.5
C5—C4—C3124.75 (11)H12A—C12—H12B109.5
C5—C4—C9118.89 (11)H12A—C12—H12C109.5
C9—C4—C3116.33 (11)H12B—C12—H12C109.5
C4—C5—H5119.9O1—C13—O2122.31 (13)
C6—C5—C4120.11 (12)O1—C13—C3125.09 (12)
C6—C5—H5119.9O2—C13—C3112.57 (11)
C5—C6—I1119.55 (10)O2—C14—H14A109.5
C7—C6—I1119.26 (10)O2—C14—H14B109.5
C7—C6—C5121.19 (12)O2—C14—H14C109.5
C6—C7—H7120.3H14A—C14—H14B109.5
C8—C7—C6119.31 (12)H14A—C14—H14C109.5
C8—C7—H7120.3H14B—C14—H14C109.5
C7—C8—C9120.73 (12)
C14—O2—C13—O13.0 (2)C2—C3—C4—C911.93 (17)
C14—O2—C13—C3175.15 (12)C13—C3—C4—C56.82 (18)
C12—O4—C11—O34.60 (19)C13—C3—C4—C9171.05 (11)
C12—O4—C11—C1177.95 (11)C2—C3—C13—O1159.19 (14)
C9—N1—C1—C240.61 (15)C2—C3—C13—O218.92 (16)
C9—N1—C1—C10163.02 (11)C4—C3—C13—O117.9 (2)
C9—N1—C1—C1179.35 (14)C4—C3—C13—O2164.00 (11)
C1—N1—C9—C428.53 (17)C3—C4—C5—C6176.90 (12)
C1—N1—C9—C8155.41 (12)C9—C4—C5—C60.92 (19)
N1—C1—C2—C328.17 (16)C3—C4—C9—N10.21 (17)
C10—C1—C2—C3148.81 (12)C3—C4—C9—C8176.28 (11)
C11—C1—C2—C392.90 (14)C5—C4—C9—N1177.79 (11)
N1—C1—C11—O314.82 (17)C5—C4—C9—C81.72 (18)
N1—C1—C11—O4167.70 (10)C4—C5—C6—I1179.18 (9)
C2—C1—C11—O3134.99 (13)C4—C5—C6—C70.5 (2)
C2—C1—C11—O447.53 (14)I1—C6—C7—C8178.59 (10)
C10—C1—C11—O3103.84 (15)C5—C6—C7—C81.1 (2)
C10—C1—C11—O473.64 (13)C6—C7—C8—C90.2 (2)
C1—C2—C3—C43.42 (18)C7—C8—C9—N1177.23 (12)
C1—C2—C3—C13173.68 (11)C7—C8—C9—C41.15 (19)
C2—C3—C4—C5170.20 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O3i0.82 (2)2.17 (2)2.9795 (19)169 (2)
C5—H5···O10.952.222.866 (2)125
C12—H12C···O1ii0.982.463.132 (2)126
Symmetry codes: (i) x+1, y+2, z+2; (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O3i0.82 (2)2.17 (2)2.9795 (19)169 (2)
C5—H5···O10.952.222.866 (2)125
C12—H12C···O1ii0.982.463.132 (2)126
Symmetry codes: (i) x+1, y+2, z+2; (ii) x+1, y+1, z+1.
 

Acknowledgements

The title compound was synthesized at RWTH Aachen University, Germany. The authors thank Professor Magnus Rueping of RWTH Aachen University for helpful discussions.

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