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ISSN: 2056-9890

Crystal structure of pyriproxyfen

aDepartment of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
*Correspondence e-mail: thkim@gnu.ac.kr, jekim@gnu.ac.kr

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 7 July 2015; accepted 14 July 2015; online 22 July 2015)

In the title compound {systematic name: 4-phen­oxy­phenyl (RS)-2-[(pyridin-2-yl)­oxy]propyl ether}, C20H19NO3, which is a juvenile hormone mimic and insecticide, the dihedral angles between the plane of the central benene ring and those of the pendant pyridine ring and phenyl ring are 78.09 (6) and 82.14 (8)°, respectively. The conformation of the O—C—C—O linkage is gauche [torsion angle = −75.0 (2)°]. In the crystal, weak aromatic ππ stacking inter­actions [centroid–centroid separation = 3.8436 (13) Å] and C—H⋯π inter­actions link adjacent mol­ecules, forming a three-dimensional network.

1. Related literature

For information on the insecticidal properties of the title compound, see: Shah et al. (2015[Shah, R. M., Shad, S. A. & Abbas, N. (2015). Pestic. Biochem. Physiol. 119, 67-73.]). For related crystal structures, see: Ji et al. (2013[Ji, J., Zhang, X. Q., Wang, K., Ju, C. F. & Chen, Q. (2013). Acta Cryst. E69, o547.]); Kang et al. (2014[Kang, G., Jeon, Y., Lee, S. & Kim, T. H. (2014). Acta Cryst. E70, o1265.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C20H19NO3

  • Mr = 321.36

  • Orthorhombic, P b c a

  • a = 10.0676 (2) Å

  • b = 8.0279 (1) Å

  • c = 40.9129 (7) Å

  • V = 3306.65 (10) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 173 K

  • 0.25 × 0.13 × 0.03 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.979, Tmax = 0.997

  • 52074 measured reflections

  • 3238 independent reflections

  • 2515 reflections with I > 2σ(I)

  • Rint = 0.065

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.148

  • S = 1.04

  • 3238 reflections

  • 218 parameters

  • H-atom parameters constrained

  • Δρmax = 0.66 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
C—H⋯π inter­actions (Å, °)

Cg1 and Cg2 are the centroids of the N1/C4/C3/C2/C1/C5 and C15–C20 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2⋯Cg1i 0.95 2.85 3.667 (3) 145
C14—H14⋯Cg2ii 0.95 2.86 3.733 (2) 152
C19—H19⋯Cg2iii 0.95 2.97 3.857 (2) 156
Symmetry codes: (i) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z]; (ii) x, y-1, z; (iii) [-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. 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: SHELXL2013 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]); molecular graphics: DIAMOND (Brandenburg, 2010[Brandenburg, K. (2010). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Pyriproxyfen, [systematic name: 4-phenoxyphenyl (RS)-2-(2-pyridyloxy)propyl ether], is the juvenile hormone mimics and it has been used for the management of many insect pests including the house fly (Shah et al., 2015). However, until now its crystal structure has not been reported. In the title compound (Fig. 1), the dihedral angles between the planes of the central benzyl ring and the terminal pyridine ring and phenyl ring system are 78.09 (6) and 82.14 (8)°, respectively. All bond lengths and bond angles are normal and comparable to those observed in the crystal structure of a similar compound (Ji et al., 2013; Kang et al., 2014).

In the crystal (Fig. 2), weak intermolecular C—H···π interactions link adjacent molecules, forming a three-dimensional network (Table. 1). In addition, weak ππ interactions [Cg1···Cg1iv, 3.8436 (13) Å] are present (Cg1 is the centroid of the N1–C5 ring)[for symmetry codes: (iv),-x + 2,-y - 1,-z].

Related literature top

For information on the insecticidal properties of the title compound, see: Shah et al. (2015). For related crystal structures, see: Ji et al. (2013); Kang et al. (2014).

Experimental top

The title compound was purchased from the Dr Ehrenstorfer GmbH Company. Slow evaporation of a solution in CH2Cl2 gave single crystals suitable for X-ray analysis in the form of colourless blocks.

Refinement top

All H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 1.00 Å, Uiso = 1.2Ueq(C) for Csp3—H, d(C—H) = 0.99 Å, Uiso = 1.2Ueq(C) for CH2 groups, d(C—H) = 0.98 Å, Uiso = 1.2Ueq(C) for CH3 groups, d(C—H) = 0.95 Å, Uiso = 1.2Ueq(C) for aromatic C—H.

Structure description top

Pyriproxyfen, [systematic name: 4-phenoxyphenyl (RS)-2-(2-pyridyloxy)propyl ether], is the juvenile hormone mimics and it has been used for the management of many insect pests including the house fly (Shah et al., 2015). However, until now its crystal structure has not been reported. In the title compound (Fig. 1), the dihedral angles between the planes of the central benzyl ring and the terminal pyridine ring and phenyl ring system are 78.09 (6) and 82.14 (8)°, respectively. All bond lengths and bond angles are normal and comparable to those observed in the crystal structure of a similar compound (Ji et al., 2013; Kang et al., 2014).

In the crystal (Fig. 2), weak intermolecular C—H···π interactions link adjacent molecules, forming a three-dimensional network (Table. 1). In addition, weak ππ interactions [Cg1···Cg1iv, 3.8436 (13) Å] are present (Cg1 is the centroid of the N1–C5 ring)[for symmetry codes: (iv),-x + 2,-y - 1,-z].

For information on the insecticidal properties of the title compound, see: Shah et al. (2015). For related crystal structures, see: Ji et al. (2013); Kang et al. (2014).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as small spheres of arbitrary radius.
[Figure 2] Fig. 2. Crystal packing viewed along the a axis. The weak C—H···π and ππ interactions are shown as dashed lines.
4-Phenoxyphenyl (RS)-2-[(pyridin-2-yl)oxy]propyl ether top
Crystal data top
C20H19NO3Dx = 1.291 Mg m3
Mr = 321.36Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 7580 reflections
a = 10.0676 (2) Åθ = 2.3–22.0°
b = 8.0279 (1) ŵ = 0.09 mm1
c = 40.9129 (7) ÅT = 173 K
V = 3306.65 (10) Å3Block, colourless
Z = 80.25 × 0.13 × 0.03 mm
F(000) = 1360
Data collection top
Bruker APEXII CCD
diffractometer
2515 reflections with I > 2σ(I)
φ and ω scansRint = 0.065
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
θmax = 26.0°, θmin = 2.0°
Tmin = 0.979, Tmax = 0.997h = 1212
52074 measured reflectionsk = 99
3238 independent reflectionsl = 5050
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.056H-atom parameters constrained
wR(F2) = 0.148 w = 1/[σ2(Fo2) + (0.0576P)2 + 2.9207P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
3238 reflectionsΔρmax = 0.66 e Å3
218 parametersΔρmin = 0.25 e Å3
Crystal data top
C20H19NO3V = 3306.65 (10) Å3
Mr = 321.36Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 10.0676 (2) ŵ = 0.09 mm1
b = 8.0279 (1) ÅT = 173 K
c = 40.9129 (7) Å0.25 × 0.13 × 0.03 mm
Data collection top
Bruker APEXII CCD
diffractometer
3238 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2515 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.997Rint = 0.065
52074 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.148H-atom parameters constrained
S = 1.04Δρmax = 0.66 e Å3
3238 reflectionsΔρmin = 0.25 e Å3
218 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
O10.93462 (16)0.1993 (2)0.07340 (4)0.0440 (4)
O20.97257 (17)0.12811 (19)0.10028 (4)0.0407 (4)
O30.84983 (16)0.6264 (2)0.18833 (4)0.0470 (4)
N10.9994 (2)0.2077 (3)0.01922 (5)0.0430 (5)
C10.8083 (2)0.3616 (3)0.03714 (6)0.0427 (6)
H10.75140.39310.05460.051*
C20.7879 (2)0.4169 (3)0.00560 (6)0.0454 (6)
H20.71640.49010.00080.054*
C30.8727 (2)0.3645 (3)0.01884 (6)0.0446 (6)
H30.85950.39930.04080.054*
C40.9750 (2)0.2626 (3)0.01099 (6)0.0443 (6)
H41.03290.22800.02800.053*
C50.9177 (2)0.2561 (3)0.04197 (5)0.0357 (5)
C61.0603 (2)0.1277 (3)0.08188 (5)0.0385 (5)
H61.09270.05790.06330.046*
C71.1605 (3)0.2635 (3)0.08878 (6)0.0516 (7)
H7A1.12730.33530.10630.077*
H7B1.24490.21310.09550.077*
H7C1.17430.33000.06900.077*
C81.0369 (3)0.0192 (3)0.11085 (6)0.0413 (6)
H8A0.98070.07810.12700.050*
H8B1.12250.00880.12140.050*
C90.9480 (2)0.2473 (3)0.12354 (5)0.0328 (5)
C100.8926 (3)0.3944 (3)0.11212 (6)0.0418 (6)
H100.87550.40790.08940.050*
C110.8624 (2)0.5218 (3)0.13372 (6)0.0419 (6)
H110.82440.62270.12600.050*
C120.8880 (2)0.5010 (3)0.16646 (6)0.0381 (5)
C130.9423 (2)0.3563 (3)0.17803 (6)0.0405 (6)
H130.95880.34370.20080.049*
C140.9732 (2)0.2277 (3)0.15657 (5)0.0389 (5)
H141.01140.12730.16450.047*
C150.9434 (2)0.7403 (3)0.19842 (5)0.0335 (5)
C161.0758 (2)0.7374 (3)0.18908 (5)0.0376 (5)
H161.10780.65480.17440.045*
C171.1612 (3)0.8584 (3)0.20167 (6)0.0441 (6)
H171.25210.85810.19550.053*
C181.1157 (3)0.9779 (3)0.22293 (6)0.0465 (6)
H181.17511.05850.23160.056*
C190.9830 (3)0.9803 (3)0.23162 (5)0.0434 (6)
H190.95101.06400.24600.052*
C200.8970 (2)0.8620 (3)0.21951 (5)0.0387 (5)
H200.80600.86390.22560.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0434 (10)0.0497 (10)0.0389 (9)0.0070 (8)0.0040 (7)0.0049 (7)
O20.0592 (10)0.0341 (8)0.0290 (8)0.0042 (8)0.0059 (7)0.0004 (6)
O30.0366 (9)0.0428 (10)0.0618 (11)0.0025 (8)0.0069 (8)0.0159 (8)
N10.0424 (11)0.0441 (12)0.0424 (11)0.0004 (9)0.0015 (9)0.0029 (9)
C10.0396 (13)0.0426 (14)0.0459 (14)0.0053 (11)0.0021 (11)0.0098 (11)
C20.0387 (13)0.0353 (13)0.0622 (16)0.0019 (11)0.0161 (12)0.0006 (12)
C30.0472 (14)0.0498 (14)0.0368 (13)0.0126 (12)0.0118 (11)0.0084 (11)
C40.0430 (14)0.0494 (15)0.0404 (13)0.0033 (12)0.0011 (11)0.0014 (11)
C50.0401 (12)0.0340 (12)0.0330 (11)0.0096 (10)0.0075 (10)0.0037 (9)
C60.0378 (13)0.0424 (13)0.0353 (12)0.0025 (11)0.0014 (10)0.0053 (10)
C70.0529 (16)0.0536 (16)0.0484 (14)0.0071 (13)0.0012 (12)0.0074 (12)
C80.0508 (14)0.0360 (13)0.0372 (12)0.0029 (11)0.0045 (10)0.0006 (10)
C90.0363 (12)0.0306 (11)0.0314 (11)0.0030 (9)0.0030 (9)0.0007 (9)
C100.0506 (14)0.0385 (13)0.0362 (12)0.0009 (11)0.0043 (11)0.0079 (10)
C110.0430 (14)0.0335 (12)0.0493 (14)0.0031 (11)0.0012 (11)0.0057 (11)
C120.0315 (11)0.0365 (12)0.0461 (13)0.0038 (10)0.0016 (10)0.0065 (10)
C130.0429 (13)0.0452 (14)0.0334 (12)0.0002 (11)0.0040 (10)0.0040 (10)
C140.0470 (14)0.0355 (12)0.0343 (12)0.0029 (11)0.0064 (10)0.0017 (10)
C150.0376 (12)0.0306 (11)0.0322 (11)0.0006 (10)0.0030 (9)0.0020 (9)
C160.0398 (13)0.0362 (12)0.0368 (12)0.0040 (10)0.0008 (10)0.0029 (10)
C170.0384 (13)0.0463 (14)0.0477 (14)0.0033 (11)0.0069 (11)0.0093 (12)
C180.0561 (16)0.0392 (13)0.0440 (13)0.0040 (12)0.0170 (12)0.0032 (11)
C190.0605 (16)0.0382 (13)0.0314 (12)0.0032 (12)0.0073 (11)0.0018 (10)
C200.0436 (13)0.0390 (12)0.0335 (12)0.0068 (11)0.0007 (10)0.0010 (10)
Geometric parameters (Å, º) top
O1—C51.375 (3)C8—H8B0.9900
O1—C61.432 (3)C9—C141.384 (3)
O2—C91.372 (3)C9—C101.387 (3)
O2—C81.416 (3)C10—C111.386 (3)
O3—C151.376 (3)C10—H100.9500
O3—C121.401 (3)C11—C121.374 (3)
N1—C51.302 (3)C11—H110.9500
N1—C41.335 (3)C12—C131.368 (3)
C1—C21.380 (3)C13—C141.391 (3)
C1—C51.404 (3)C13—H130.9500
C1—H10.9500C14—H140.9500
C2—C31.380 (4)C15—C201.385 (3)
C2—H20.9500C15—C161.387 (3)
C3—C41.354 (4)C16—C171.395 (3)
C3—H30.9500C16—H160.9500
C4—H40.9500C17—C181.373 (4)
C6—C81.490 (3)C17—H170.9500
C6—C71.511 (3)C18—C191.382 (4)
C6—H61.0000C18—H180.9500
C7—H7A0.9800C19—C201.377 (3)
C7—H7B0.9800C19—H190.9500
C7—H7C0.9800C20—H200.9500
C8—H8A0.9900
C5—O1—C6117.96 (18)O2—C9—C14124.4 (2)
C9—O2—C8116.94 (16)O2—C9—C10115.65 (19)
C15—O3—C12118.77 (17)C14—C9—C10120.0 (2)
C5—N1—C4116.5 (2)C11—C10—C9120.1 (2)
C2—C1—C5116.3 (2)C11—C10—H10119.9
C2—C1—H1121.9C9—C10—H10119.9
C5—C1—H1121.9C12—C11—C10119.4 (2)
C1—C2—C3119.1 (2)C12—C11—H11120.3
C1—C2—H2120.4C10—C11—H11120.3
C3—C2—H2120.4C13—C12—C11121.0 (2)
C4—C3—C2118.9 (2)C13—C12—O3119.9 (2)
C4—C3—H3120.6C11—C12—O3118.9 (2)
C2—C3—H3120.6C12—C13—C14120.1 (2)
N1—C4—C3124.0 (2)C12—C13—H13119.9
N1—C4—H4118.0C14—C13—H13119.9
C3—C4—H4118.0C9—C14—C13119.4 (2)
N1—C5—O1119.5 (2)C9—C14—H14120.3
N1—C5—C1125.1 (2)C13—C14—H14120.3
O1—C5—C1115.4 (2)O3—C15—C20115.1 (2)
O1—C6—C8106.72 (19)O3—C15—C16124.4 (2)
O1—C6—C7110.2 (2)C20—C15—C16120.5 (2)
C8—C6—C7112.2 (2)C15—C16—C17118.6 (2)
O1—C6—H6109.2C15—C16—H16120.7
C8—C6—H6109.2C17—C16—H16120.7
C7—C6—H6109.2C18—C17—C16121.0 (2)
C6—C7—H7A109.5C18—C17—H17119.5
C6—C7—H7B109.5C16—C17—H17119.5
H7A—C7—H7B109.5C17—C18—C19119.6 (2)
C6—C7—H7C109.5C17—C18—H18120.2
H7A—C7—H7C109.5C19—C18—H18120.2
H7B—C7—H7C109.5C20—C19—C18120.4 (2)
O2—C8—C6108.52 (18)C20—C19—H19119.8
O2—C8—H8A110.0C18—C19—H19119.8
C6—C8—H8A110.0C19—C20—C15119.9 (2)
O2—C8—H8B110.0C19—C20—H20120.1
C6—C8—H8B110.0C15—C20—H20120.1
H8A—C8—H8B108.4
C5—C1—C2—C31.1 (3)C10—C11—C12—C130.3 (4)
C1—C2—C3—C41.2 (4)C10—C11—C12—O3176.2 (2)
C5—N1—C4—C30.5 (4)C15—O3—C12—C1386.0 (3)
C2—C3—C4—N10.4 (4)C15—O3—C12—C1198.0 (3)
C4—N1—C5—O1177.7 (2)C11—C12—C13—C140.4 (4)
C4—N1—C5—C10.7 (3)O3—C12—C13—C14176.3 (2)
C6—O1—C5—N117.0 (3)O2—C9—C14—C13179.0 (2)
C6—O1—C5—C1164.4 (2)C10—C9—C14—C130.2 (3)
C2—C1—C5—N10.1 (3)C12—C13—C14—C90.4 (4)
C2—C1—C5—O1178.6 (2)C12—O3—C15—C20178.8 (2)
C5—O1—C6—C8157.85 (19)C12—O3—C15—C161.8 (3)
C5—O1—C6—C780.0 (2)O3—C15—C16—C17178.6 (2)
C9—O2—C8—C6177.21 (19)C20—C15—C16—C170.7 (3)
O1—C6—C8—O275.0 (2)C15—C16—C17—C180.1 (3)
C7—C6—C8—O2164.1 (2)C16—C17—C18—C191.0 (4)
C8—O2—C9—C144.7 (3)C17—C18—C19—C201.1 (3)
C8—O2—C9—C10176.0 (2)C18—C19—C20—C150.2 (3)
O2—C9—C10—C11179.2 (2)O3—C15—C20—C19178.7 (2)
C14—C9—C10—C110.1 (4)C16—C15—C20—C190.7 (3)
C9—C10—C11—C120.1 (4)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the N1/C4/C3/C2/C1/C5 and C15–C20 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C2—H2···Cg1i0.952.853.667 (3)145
C14—H14···Cg2ii0.952.863.733 (2)152
C19—H19···Cg2iii0.952.973.857 (2)156
Symmetry codes: (i) x+3/2, y1/2, z; (ii) x, y1, z; (iii) x+2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the N1/C4/C3/C2/C1/C5 and C15–C20 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C2—H2···Cg1i0.952.853.667 (3)145
C14—H14···Cg2ii0.952.863.733 (2)152
C19—H19···Cg2iii0.952.973.857 (2)156
Symmetry codes: (i) x+3/2, y1/2, z; (ii) x, y1, z; (iii) x+2, y+1/2, z+1/2.
 

Acknowledgements

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2015R1D1A4A01020317).

References

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