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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o1973.
Published online 2009 July 25. doi:  10.1107/S1600536809028281
PMCID: PMC2977144

p-Tolyl bis­(p-tolyl­amido)phosphate

Abstract

In the title compound, C21H23N2O2P, the P atom exhibits tetra­hedral coordination; the P—N bond lengths are relatively short [1.6297 (13) and 1.6424 (13) Å]. In the crystal, adjacent mol­ecules are linked by N—H(...)O hydrogen bonds into a zigzag chain running along the c axis.

Related literature

For related compounds, see: Pourayoubi & Sabbaghi (2007 [triangle]); Ghadimi et al. (2007 [triangle]); Gholivand et al. (2001 [triangle]). For bond-length data, see: Corbridge (1995 [triangle]).

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Object name is e-65-o1973-scheme1.jpg

Experimental

Crystal data

  • C21H23N2O2P
  • M r = 366.38
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1973-efi1.jpg
  • a = 14.0977 (6) Å
  • b = 14.7657 (6) Å
  • c = 9.5155 (4) Å
  • β = 104.676 (1)°
  • V = 1916.14 (14) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.16 mm−1
  • T = 100 K
  • 0.40 × 0.26 × 0.20 mm

Data collection

  • Bruker APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.939, T max = 0.969
  • 18737 measured reflections
  • 5555 independent reflections
  • 4484 reflections with I > 2σ(I)
  • R int = 0.033

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.107
  • S = 1.02
  • 5555 reflections
  • 243 parameters
  • 2 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.62 e Å−3
  • Δρmin = −0.50 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT (Bruker, 2005 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809028281/ng2606sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809028281/ng2606Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

Support of this investigation by the Imam Hossein University is gratefully acknowledged.

supplementary crystallographic information

Comment

In the previous works about phosphoramidates and phosphoric acid esters, some derivatives have been structurally discussed such as [(CH3)2N][4-H3C—C6H4—O]P(O)CN (Ghadimi et al., 2007), [(CH3)2N]P(O)[O—C6H4-(4-NO2)]2 (Gholivand et al., 2001) and [(C6H5CH2)(CH(CH3)2)NH2][CCl3C(O)NHP(O)(O)(OCH3)] (Pourayoubi & Sabbaghi, 2007). Here, synthesis and crystal structure of a new phosphoramido acid ester, [4-H3C—C6H4O]P(O)[NHC6H4-4-CH3]2, are reported. The title compound was synthesized from the reaction of (4-tolyl)-dichlorophosphate with an excess amount of para-toluidine (1:4 mole ratios). Single crystals were obtained from CHCl3/CH3CN at room temperature. Molecular structure of [4-H3C—C6H4O]P(O)[NHC6H4-4-CH3]2 is shown in Fig. 1. The phosphorus atom has distorted tetrahedral configuration. The bond angles around P atom are in the range of 96.93 (6)° [for the O(2)—P(1)—N(1) angle] to 119.08 (7)° [for the O(1)—P(1)—N(1) angle]. The oxygen atom of OC6H4-4-CH3 moiety has sp2 character (the C(15)—O(2)—P(1) angle is 119.58 (9)°, also the P(1)—O(2) bond length of 1.6072 (11) Å is smaller than the P—O single bond length. The P(1)—O(1) bond length (1.4765 (11) Å) is longer than the normal P===O bond length [1.45 Å for P(O)Cl3, (Corbridge, 1995)]. The P—N bond lengths in title compound are shorter than the P—N single bond length [1.77 Å for NaHPO3NH2, (Corbridge, 1995)]. Moreover, the nitrogen atoms have sp2 hybridization. Sum of the surrounding angles around N(1) and N(2) atoms are 359.7° & 360.0°, respectively. H-bonded chain of title compound is formed via two different types of N—H···O===P hydrogen bond. A view of unit cell packing showing the N—H···O===P hydrogen bond is given in Fig. 2.

Experimental

To a solution of (4-tolyl)-dichlorophosphate (2.250 g, 10 mmol) in 15 ml dry acetonitrile, a solution of para-toluidine (4.286 g, 40 mmol) in 30 ml acetonitrile was added at 0°C. After 4 h stirring, the solvent was evaporated in vacuum. The solid was washed with distilled water. Single crystals of the product were obtained from a solution of chloroform-acetonitrile (4:1) after a slow evaporation at room temperature. 1H NMR (250.13 MHz, CDCl3, 25°C, TMS), δ (p.p.m.): 2.17 (s, 6H, p-CH3), 2.25 (s, 3H, p-CH3), 6.95–7.00 (m, 8H, Ar—H), 7.03–7.15 (m, 4H, Ar—H), 8.15 (d, 2J(PNH) = 9.8 Hz, 2H, NH); 13C NMR (62.90 MHz, CDCl3, 25°C, TMS), δ (p.p.m.): 20.69 (s, 2 C, p-CH3), 2.77 (s, 1 C, p-CH3), 117.98 (d, 3J(P,C) = 7.6 Hz, Cortho), 120.77 (d, 3J(P,C) = 4.6 Hz, Cortho), 129.81 (s), 129.96 (s), 130.47 (s), 134.24 (s), 138.70 (d, 2J(P,C) = 1.8 Hz, 2 C, Cipso), 148.59 (d, 2J(P,C) = 6.5 Hz, 1 C, Cipso); 31P{1H} NMR (101.25 MHz, CDCl3, 25°C, H3PO4 external), δ (p.p.m.): 1.23 (s); 31P NMR, δ (p.p.m.): 1.23 (t, 2J(HNP) = 9.8 Hz). IR (KBr, cm-1): 3220 (NH), 2950, 2935, 1610, 1515, 1430, 1320, 1240 (P===O), 1190, 1150, 1125, 975, 915, 725.

Refinement

The hydrogen atoms of NH groups were found in difference Fourier synthesis and refined in isotropic approximation with a distance restraint (DFIX 0.88 0.01). The H(C) atom positions were calculated. H atoms were refined in isotropic approximatiom in riding model with the Uiso(H) parameters equal to 1.2 Ueq(Ni), 1.2 Ueq(Ci) or 1.5 Ueq(Cii), where U(Ci) and U(Cii) are respectively the equivalent thermal parameters of nitrogen and carbon atoms of CH and CH3 groups to which corresponding H atoms are bonded.

Figures

Fig. 1.
Molecular structure and atom-labeling scheme for [4-H3C—C6H4O]P(O)[NHC6H4-4-CH3]2 (50% probability ellipsoids).
Fig. 2.
A view of unit cell packing of title compound.

Crystal data

C21H23N2O2PF(000) = 776
Mr = 366.38Dx = 1.270 Mg m3Dm = 0 Mg m3Dm measured by not measured
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 552 reflections
a = 14.0977 (6) Åθ = 3–30°
b = 14.7657 (6) ŵ = 0.16 mm1
c = 9.5155 (4) ÅT = 100 K
β = 104.676 (1)°Needle, colorless
V = 1916.14 (14) Å30.40 × 0.26 × 0.20 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer5555 independent reflections
Radiation source: fine-focus sealed tube4484 reflections with I > 2σ(I)
graphiteRint = 0.033
ω scansθmax = 30.0°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −19→19
Tmin = 0.939, Tmax = 0.969k = −20→16
18737 measured reflectionsl = −13→13

Refinement

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) = 0.107H atoms treated by a mixture of independent and constrained refinement
S = 1.02w = 1/[σ2(Fo2) + (0.0306P)2 + 1.982P] where P = (Fo2 + 2Fc2)/3
5555 reflections(Δ/σ)max < 0.001
243 parametersΔρmax = 0.62 e Å3
2 restraintsΔρmin = −0.50 e Å3

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 (Å2)

xyzUiso*/Ueq
P10.30676 (3)0.73955 (3)0.60541 (4)0.01332 (9)
O10.37549 (8)0.77353 (7)0.52354 (11)0.0174 (2)
O20.27068 (8)0.81531 (7)0.70157 (11)0.0165 (2)
N10.34582 (9)0.66666 (8)0.73586 (13)0.0154 (2)
H1N0.3574 (14)0.6865 (13)0.8256 (12)0.020 (5)*
N20.20970 (9)0.69923 (9)0.48821 (13)0.0164 (2)
H2N0.2157 (13)0.6978 (12)0.3983 (11)0.014 (4)*
C10.37149 (10)0.57578 (10)0.71581 (15)0.0153 (3)
C20.38112 (14)0.51526 (11)0.83062 (17)0.0249 (3)
H2A0.37250.53530.91920.030*
C30.40352 (14)0.42486 (12)0.81343 (19)0.0269 (4)
H3A0.41040.38530.89140.032*
C40.41580 (11)0.39238 (11)0.68168 (18)0.0198 (3)
C50.40809 (11)0.45397 (11)0.56929 (17)0.0189 (3)
H5A0.41700.43390.48090.023*
C60.38729 (11)0.54520 (10)0.58541 (16)0.0173 (3)
H6A0.38400.58540.50910.021*
C70.43533 (13)0.29353 (12)0.6595 (2)0.0277 (4)
H7A0.44150.28450.56230.042*
H7B0.38190.25780.67450.042*
H7C0.49500.27550.72760.042*
C80.11965 (11)0.66800 (10)0.51075 (16)0.0163 (3)
C90.04290 (12)0.64951 (11)0.38934 (16)0.0209 (3)
H9A0.05170.65820.29670.025*
C10−0.04647 (12)0.61819 (12)0.40582 (18)0.0227 (3)
H10A−0.09640.60520.32370.027*
C11−0.06289 (11)0.60580 (11)0.54274 (18)0.0201 (3)
C120.01388 (12)0.62506 (12)0.66285 (17)0.0222 (3)
H12A0.00440.61770.75540.027*
C130.10467 (12)0.65499 (11)0.64861 (16)0.0206 (3)
H13A0.15520.66630.73090.025*
C14−0.16075 (12)0.57270 (13)0.5597 (2)0.0273 (4)
H14A−0.15870.56830.66100.041*
H14B−0.17460.51420.51510.041*
H14C−0.21120.61460.51360.041*
C150.24805 (11)0.90316 (10)0.64444 (15)0.0160 (3)
C160.31733 (11)0.97067 (10)0.68618 (16)0.0173 (3)
H16A0.37930.95760.74500.021*
C170.29238 (12)1.05864 (11)0.63823 (17)0.0206 (3)
H17A0.33811.10480.66670.025*
C180.20005 (12)1.07898 (11)0.54811 (17)0.0227 (3)
C190.13342 (12)1.00877 (12)0.50624 (18)0.0249 (3)
H19A0.07221.02100.44460.030*
C200.15618 (12)0.92020 (11)0.55447 (17)0.0215 (3)
H20A0.11070.87380.52680.026*
C210.17365 (16)1.17477 (13)0.4986 (2)0.0355 (4)
H21A0.10791.17620.43800.053*
H21B0.21821.19620.44460.053*
H21C0.17811.21290.58180.053*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.01640 (17)0.01403 (17)0.00997 (15)−0.00111 (13)0.00415 (12)0.00019 (13)
O10.0192 (5)0.0202 (5)0.0135 (5)−0.0029 (4)0.0054 (4)0.0016 (4)
O20.0236 (5)0.0143 (5)0.0129 (4)0.0008 (4)0.0068 (4)0.0008 (4)
N10.0225 (6)0.0140 (6)0.0100 (5)−0.0003 (5)0.0046 (4)−0.0003 (4)
N20.0165 (6)0.0222 (6)0.0108 (5)−0.0028 (5)0.0041 (4)−0.0006 (5)
C10.0152 (6)0.0152 (7)0.0154 (6)−0.0011 (5)0.0034 (5)−0.0001 (5)
C20.0386 (9)0.0204 (8)0.0178 (7)0.0034 (7)0.0111 (6)0.0029 (6)
C30.0383 (9)0.0196 (8)0.0239 (8)0.0049 (7)0.0102 (7)0.0074 (6)
C40.0139 (6)0.0170 (7)0.0272 (8)0.0010 (5)0.0026 (6)−0.0011 (6)
C50.0166 (7)0.0203 (7)0.0203 (7)−0.0004 (6)0.0054 (5)−0.0043 (6)
C60.0196 (7)0.0174 (7)0.0157 (6)−0.0011 (6)0.0061 (5)0.0005 (5)
C70.0245 (8)0.0183 (8)0.0375 (9)0.0046 (6)0.0025 (7)−0.0010 (7)
C80.0170 (7)0.0156 (7)0.0166 (6)−0.0004 (5)0.0049 (5)−0.0004 (5)
C90.0220 (7)0.0248 (8)0.0152 (6)−0.0006 (6)0.0033 (6)0.0003 (6)
C100.0181 (7)0.0253 (8)0.0224 (7)−0.0016 (6)0.0010 (6)−0.0010 (6)
C110.0178 (7)0.0162 (7)0.0269 (8)0.0005 (6)0.0068 (6)0.0012 (6)
C120.0234 (7)0.0255 (8)0.0202 (7)−0.0026 (6)0.0100 (6)0.0015 (6)
C130.0201 (7)0.0259 (8)0.0158 (6)−0.0056 (6)0.0044 (5)−0.0013 (6)
C140.0192 (7)0.0265 (9)0.0369 (9)−0.0019 (6)0.0084 (7)0.0020 (7)
C150.0213 (7)0.0145 (7)0.0131 (6)0.0012 (5)0.0063 (5)0.0005 (5)
C160.0187 (7)0.0181 (7)0.0151 (6)0.0017 (6)0.0039 (5)0.0000 (5)
C170.0248 (8)0.0163 (7)0.0200 (7)−0.0015 (6)0.0045 (6)−0.0008 (6)
C180.0270 (8)0.0186 (7)0.0212 (7)0.0046 (6)0.0035 (6)0.0016 (6)
C190.0218 (7)0.0249 (8)0.0244 (8)0.0044 (6)−0.0008 (6)0.0032 (6)
C200.0206 (7)0.0212 (8)0.0209 (7)−0.0025 (6)0.0019 (6)0.0004 (6)
C210.0402 (11)0.0207 (9)0.0380 (10)0.0062 (8)−0.0041 (8)0.0041 (7)

Geometric parameters (Å, °)

P1—O11.4765 (11)C9—H9A0.9300
P1—O21.6072 (11)C10—C111.392 (2)
P1—N11.6297 (13)C10—H10A0.9300
P1—N21.6424 (13)C11—C121.390 (2)
O2—C151.4114 (17)C11—C141.510 (2)
N1—C11.4153 (19)C12—C131.393 (2)
N1—H1N0.878 (9)C12—H12A0.9300
N2—C81.4171 (19)C13—H13A0.9300
N2—H2N0.881 (9)C14—H14A0.9600
C1—C61.390 (2)C14—H14B0.9600
C1—C21.391 (2)C14—H14C0.9600
C2—C31.391 (2)C15—C161.382 (2)
C2—H2A0.9300C15—C201.383 (2)
C3—C41.393 (2)C16—C171.392 (2)
C3—H3A0.9300C16—H16A0.9300
C4—C51.387 (2)C17—C181.398 (2)
C4—C71.510 (2)C17—H17A0.9300
C5—C61.395 (2)C18—C191.388 (2)
C5—H5A0.9300C18—C211.507 (2)
C6—H6A0.9300C19—C201.396 (2)
C7—H7A0.9600C19—H19A0.9300
C7—H7B0.9600C20—H20A0.9300
C7—H7C0.9600C21—H21A0.9600
C8—C131.394 (2)C21—H21B0.9600
C8—C91.395 (2)C21—H21C0.9600
C9—C101.388 (2)
O1—P1—O2114.12 (6)C9—C10—C11121.37 (15)
O1—P1—N1119.08 (7)C9—C10—H10A119.3
O2—P1—N196.93 (6)C11—C10—H10A119.3
O1—P1—N2108.07 (6)C12—C11—C10117.60 (14)
O2—P1—N2108.03 (6)C12—C11—C14121.38 (15)
N1—P1—N2109.90 (7)C10—C11—C14121.02 (15)
C15—O2—P1119.58 (9)C11—C12—C13121.89 (14)
C1—N1—P1124.90 (10)C11—C12—H12A119.1
C1—N1—H1N117.2 (13)C13—C12—H12A119.1
P1—N1—H1N117.6 (13)C12—C13—C8119.83 (14)
C8—N2—P1129.74 (10)C12—C13—H13A120.1
C8—N2—H2N116.7 (12)C8—C13—H13A120.1
P1—N2—H2N113.6 (12)C11—C14—H14A109.5
C6—C1—C2119.10 (14)C11—C14—H14B109.5
C6—C1—N1122.17 (13)H14A—C14—H14B109.5
C2—C1—N1118.73 (13)C11—C14—H14C109.5
C3—C2—C1120.27 (15)H14A—C14—H14C109.5
C3—C2—H2A119.9H14B—C14—H14C109.5
C1—C2—H2A119.9C16—C15—C20121.99 (14)
C2—C3—C4121.32 (15)C16—C15—O2118.56 (13)
C2—C3—H3A119.3C20—C15—O2119.37 (13)
C4—C3—H3A119.3C15—C16—C17118.52 (14)
C5—C4—C3117.69 (15)C15—C16—H16A120.7
C5—C4—C7120.50 (15)C17—C16—H16A120.7
C3—C4—C7121.80 (15)C16—C17—C18121.35 (15)
C4—C5—C6121.72 (14)C16—C17—H17A119.3
C4—C5—H5A119.1C18—C17—H17A119.3
C6—C5—H5A119.1C19—C18—C17118.22 (15)
C1—C6—C5119.82 (14)C19—C18—C21121.04 (15)
C1—C6—H6A120.1C17—C18—C21120.74 (16)
C5—C6—H6A120.1C18—C19—C20121.53 (15)
C4—C7—H7A109.5C18—C19—H19A119.2
C4—C7—H7B109.5C20—C19—H19A119.2
H7A—C7—H7B109.5C15—C20—C19118.37 (15)
C4—C7—H7C109.5C15—C20—H20A120.8
H7A—C7—H7C109.5C19—C20—H20A120.8
H7B—C7—H7C109.5C18—C21—H21A109.5
C13—C8—C9118.80 (14)C18—C21—H21B109.5
C13—C8—N2122.85 (13)H21A—C21—H21B109.5
C9—C8—N2118.35 (13)C18—C21—H21C109.5
C10—C9—C8120.49 (14)H21A—C21—H21C109.5
C10—C9—H9A119.8H21B—C21—H21C109.5
C8—C9—H9A119.8
O1—P1—O2—C1540.60 (12)C13—C8—C9—C10−0.4 (2)
N1—P1—O2—C15166.81 (11)N2—C8—C9—C10179.56 (15)
N2—P1—O2—C15−79.60 (11)C8—C9—C10—C111.1 (3)
O1—P1—N1—C1−69.46 (14)C9—C10—C11—C12−0.6 (2)
O2—P1—N1—C1167.95 (12)C9—C10—C11—C14179.31 (16)
N2—P1—N1—C155.89 (14)C10—C11—C12—C13−0.5 (2)
O1—P1—N2—C8−172.64 (13)C14—C11—C12—C13179.52 (16)
O2—P1—N2—C8−48.71 (15)C11—C12—C13—C81.2 (3)
N1—P1—N2—C855.93 (15)C9—C8—C13—C12−0.7 (2)
P1—N1—C1—C615.1 (2)N2—C8—C13—C12179.30 (15)
P1—N1—C1—C2−164.86 (13)P1—O2—C15—C16−99.59 (14)
C6—C1—C2—C3−1.8 (3)P1—O2—C15—C2083.48 (16)
N1—C1—C2—C3178.16 (16)C20—C15—C16—C171.4 (2)
C1—C2—C3—C4−0.7 (3)O2—C15—C16—C17−175.40 (13)
C2—C3—C4—C52.1 (3)C15—C16—C17—C18−0.9 (2)
C2—C3—C4—C7−177.02 (17)C16—C17—C18—C19−0.5 (2)
C3—C4—C5—C6−1.0 (2)C16—C17—C18—C21179.21 (16)
C7—C4—C5—C6178.12 (15)C17—C18—C19—C201.4 (3)
C2—C1—C6—C52.9 (2)C21—C18—C19—C20−178.31 (17)
N1—C1—C6—C5−177.10 (14)C16—C15—C20—C19−0.6 (2)
C4—C5—C6—C1−1.5 (2)O2—C15—C20—C19176.23 (14)
P1—N2—C8—C13−9.5 (2)C18—C19—C20—C15−0.9 (3)
P1—N2—C8—C9170.57 (12)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.88 (1)1.93 (1)2.805 (2)176 (2)
N2—H2N···O2ii0.88 (1)2.21 (1)3.068 (2)165 (2)

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) x, −y+3/2, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NG2606).

References

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  • Corbridge, D. E. C. (1995). Phosphorus, an Outline of its Chemistry, Biochemistry and Technology, 5th ed., p. 1179. New York: Elsevier Science.
  • Ghadimi, S., Valmoozi, A. A. E. & Pourayoubi, M. (2007). Acta Cryst. E63, o3260.
  • Gholivand, K., Tadjarodi, A., Taeb, A., Garivani, G. & Ng, S. W. (2001). Acta Cryst. E57, o472–o473.
  • Pourayoubi, M. & Sabbaghi, F. (2007). Acta Cryst. E63, o4366.
  • Sheldrick, G. M. (1996). SADABS University of Göttingen, Germany.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

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