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

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ISSN: 2056-9890

1,3-Bis[(5-amino­furan-2-yl)meth­yl]-3,4,5,6-tetra­hydro­pyrimidin-1-ium hexa­fluoro­phosphate

aDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, bDepartment of Chemistry, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, cDepartment of Chemistry, Faculty of Arts and Sciences, Inönü University, 44280, Malatya, Turkey, and dDepartment of Physics, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 18 July 2013; accepted 22 July 2013; online 27 July 2013)

The asymmetric unit of the title salt, C16H21N2O2+·PF6, contains half of the whole ion pair, which has crystallographic mirror symmetry. Two F atoms related by the mirror plane are disordered over two sites of equal occupancy. The dihedral angle between the central ring and the furan ring is 59.3 ()°. In the crystal, the anions and cations are linked through C—H⋯F inter­actions, forming a three-dimensional network.

Related literature

N-heterocyclic carbene (NHC)-metal complexes have attracted much attention, particularly for their functions in catalytic reactions, see: Akkoç & Gök (2013[Akkoç, S. & Gök, Y. (2013). J. Coord. Chem. 66, 1396-1404.]); Arduengo et al. (1992[Arduengo, A. J., Rasika, H. V., Harlow, R. L. & Kline, M. J. (1992). J. Am. Chem. Soc. 114, 5530-5534.]); Bagherzadeh et al. (2012[Bagherzadeh, M., Amini, M., Ellero, A. & Woo, L. K. (2012). Inorg. Chim. Acta, 383, 46-51.]); Hermann (2002[Hermann, W. A. (2002). Angew. Chem. Int. Ed. 41, 1290-1309.]); Lee et al. (2013[Lee, C. S., Lai, Y. B., Lin, W. J., Zhuang, R. R. & Hwang, W. S. (2013). J. Organomet. Chem. 724, 235-243.]); Saba et al. (1991[Saba, S., Brescia, A. & Kaloustian, M. K. (1991). Tetrahedron Lett. 32, 5031-5034.]); Yiğit et al. (2007[Yiğit, M., Özdemir, İ., Çetinkaya, E. & Çetinkaya, B. (2007). Transition Met. Chem. 32, 536-540.]); Özdemir et al. (2001[Özdemir, İ., Yiğit, B., Çetinkaya, B., Ülkü, D., Tahir, M. N. & Arıcı, C. (2001). J. Organomet. Chem. 633, 27-32.]); Çetinkaya et al. (1997[Çetinkaya, B., Özdemir, İ., Bruneau, C. & Dixneuf, P. H. (1997). J. Mol. Catal. A Chem. 118, L1-L4.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C16H21N2O2+·PF6

  • Mr = 418.32

  • Monoclinic, P 21 /m

  • a = 6.0793 (6) Å

  • b = 18.879 (2) Å

  • c = 8.5750 (9) Å

  • β = 100.747 (5)°

  • V = 966.90 (17) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.21 mm−1

  • T = 296 K

  • 0.35 × 0.28 × 0.23 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: part of the refinement model (ΔF) (XABS2; Parkin et al., 1995[Parkin, S., Moezzi, B. & Hope, H. (1995). J. Appl. Cryst. 28, 53-56.]) Tmin = 0.932, Tmax = 0.953

  • 1677 measured reflections

  • 1677 independent reflections

  • 1089 reflections with I > 2σ(I)

  • Rint = 0.000

Refinement
  • R[F2 > 2σ(F2)] = 0.077

  • wR(F2) = 0.247

  • S = 1.08

  • 1677 reflections

  • 144 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.55 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯F2i 0.93 2.40 3.312 (8) 167
C1—H1⋯F4ii 0.93 2.52 3.044 (8) 116
Symmetry codes: (i) x, y, z-1; (ii) x-1, y, z-1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). 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.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON.

Supporting information


Comment top

1,3-Di(5-methylfurfuryl)pyrimidinium hexafluorophosphate salt is conventional N-heterocyclic carbene (NHC) precursors. N-heterocyclic carbenes (NHCs) are generally considered as analogues of phosphine ligands because of their good s-donating but very weak p-accepting ability (Arduengo et al., 1992). Normally, NHC-metal complexes have higher stability toward heat, moisture, and oxygen than phosphine metal based complexes, which makes them quite attractive as phosphine substitute. In recent years, NHCs are fully used as organocatalysts and ancillary ligands in transition metal catalyzed reactions (Hermann, 2002). They have attracted many attention, particularly for its functions in catalytic reactions (Akkoç & Gök, 2013; Lee et al., 2013; Bagherzadeh et al., 2012; Çetinkaya et al., 1997; Özdemir et al., 2001; Saba et al., 1991; Yiğit et al., 2007).

Fig. 1 shows the whole molecule (I) whose anions and cations form two parts with a crystallographic mirror symmetry. The C1–N1–C2–C3, C1–N1–C4–C5, C2–N1–C4–C5, N1–C4–C5–O1 and N1–C4–C5–C6 torsion angles are -25.1 (6), -121.5 (4), 60.4 (5), -85.1 (4) and 96.4 (6) °, respectively. All bond lengths of (I) are within normal values (Allen et al., 1987).

The crystal structure is stabilized by C—H···F interactions between the anions and cations of (I), forming a three dimensional network (Table 1, Figures 2 and 3).

Related literature top

N-heterocyclic carbene (NHC)-metal complexes have attracted much attention, particularly for their functions in catalytic reactions, see: Akkoç & Gök (2013); Arduengo et al. (1992); Bagherzadeh et al. (2012); Hermann (2002); Lee et al. (2013); Saba et al. (1991); Yiğit et al. (2007); Özdemir et al. (2001); Çetinkaya et al. (1997). For bond-length data, see: Allen et al. (1987).

Experimental top

The reaction for the preparation of heterocyclic salt containing furan moiety was carried out under argon in flame dried glassware using standard Schlenk type flasks. The synthesis of salt containing furan moiety was achieved by the reaction of N,N'-dialkylpropane-1,3-diamine (1.0 mmol) with ammonium hexafluorophosphate (1.0 mmol) in triethyl orthoformate (5 ml) (Scheme 1). The reaction mixture was heated for 12 h at 353 K. A white solid was precipitated. The precipitation was then crystallized from Et2O/EtOH (2:1) at room temperature. The resulting 1,3-di(5-methylfurfuryl)pyrimidinium hexafluorophosphate salt was obtained in good yield.

Refinement top

All H atoms were positioned geometrically and refined by using a riding model, with C—H = 0.93 - 0.97 Å and Uiso(H) = 1.2 or 1.5Ueq(C). The one fluoride atom of the hexafluorophosphate group are disordered over two sites as F5 and F6 in Fig. 1, with equal occupancies of 0.5. Mirror symmetry transformation generates the other equivalent disordered atoms (F5a and F6a in Fig. 1).

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: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with a crystallographic mirror symmetry. Displacement ellipsoids are shown at the 20% probability levels. The disordered F5, F6 and F5a, F5b atoms are related to each other with a mirror symmetry operation. Symmetry codes: (a) x, 1/2 - y, z; (b) x, 1/2 - y, z.
[Figure 2] Fig. 2. View of the crystal packing and the hydrogen bonding of (I) along a axis. H atoms not involved in hydrogen bonding are omitted for clarity.
[Figure 3] Fig. 3. View of the crystal packing and the hydrogen bonding of (I) along c axis. H atoms not involved in hydrogen bonding are omitted for clarity.
1,3-Bis[(5-aminofuran-2-yl)methyl]-3,4,5,6-tetrahydropyrimidin-1-ium hexafluorophosphate top
Crystal data top
C16H21N2O2+·PF6F(000) = 432
Mr = 418.32Dx = 1.437 Mg m3
Monoclinic, P21/mMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybCell parameters from 1100 reflections
a = 6.0793 (6) Åθ = 2.5–25°
b = 18.879 (2) ŵ = 0.21 mm1
c = 8.5750 (9) ÅT = 296 K
β = 100.747 (5)°Prism, colourless
V = 966.90 (17) Å30.35 × 0.28 × 0.23 mm
Z = 2
Data collection top
Bruker Kappa APEXII CCD
diffractometer
1677 independent reflections
Radiation source: fine-focus sealed tube1089 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.000
ω scansθmax = 24.7°, θmin = 2.2°
Absorption correction: part of the refinement model (ΔF)
(XABS2; Parkin et al., 1995)
h = 77
Tmin = 0.932, Tmax = 0.953k = 022
1677 measured reflectionsl = 010
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)] = 0.077Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.247H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.1389P)2 + 0.421P]
where P = (Fo2 + 2Fc2)/3
1677 reflections(Δ/σ)max < 0.001
144 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.55 e Å3
Crystal data top
C16H21N2O2+·PF6V = 966.90 (17) Å3
Mr = 418.32Z = 2
Monoclinic, P21/mMo Kα radiation
a = 6.0793 (6) ŵ = 0.21 mm1
b = 18.879 (2) ÅT = 296 K
c = 8.5750 (9) Å0.35 × 0.28 × 0.23 mm
β = 100.747 (5)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
1677 independent reflections
Absorption correction: part of the refinement model (ΔF)
(XABS2; Parkin et al., 1995)
1089 reflections with I > 2σ(I)
Tmin = 0.932, Tmax = 0.953Rint = 0.000
1677 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0770 restraints
wR(F2) = 0.247H-atom parameters constrained
S = 1.08Δρmax = 0.36 e Å3
1677 reflectionsΔρmin = 0.55 e Å3
144 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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*/UeqOcc. (<1)
O10.0509 (5)0.46898 (16)0.2298 (3)0.0808 (11)
N10.1021 (5)0.31127 (19)0.1262 (4)0.0706 (11)
C10.0850 (8)0.250000.0606 (6)0.069 (2)
C20.1511 (9)0.3154 (3)0.2862 (5)0.0872 (17)
C30.2709 (14)0.250000.3206 (9)0.106 (3)
C40.0792 (7)0.3771 (2)0.0383 (5)0.0817 (16)
C50.1016 (7)0.4235 (2)0.1168 (5)0.0725 (16)
C60.3108 (8)0.4325 (3)0.1001 (6)0.091 (2)
C70.4019 (9)0.4871 (3)0.2040 (6)0.094 (2)
C80.2431 (9)0.5075 (3)0.2828 (5)0.0852 (17)
C90.2247 (12)0.5625 (3)0.4039 (7)0.120 (3)
P10.3506 (2)0.250000.73427 (19)0.0793 (7)
F10.3265 (10)0.250000.5584 (6)0.247 (6)
F20.0993 (9)0.250000.7207 (8)0.236 (6)
F30.3704 (10)0.250000.9155 (7)0.218 (5)
F40.6000 (9)0.250000.7399 (8)0.260 (7)
F50.449 (3)0.3183 (5)0.7947 (15)0.204 (7)0.500
F60.258 (3)0.3213 (5)0.699 (2)0.260 (8)0.500
H10.058100.250000.042600.0820*
H2A0.243300.356600.295000.1050*
H2B0.012700.320200.362700.1050*
H3A0.284900.250000.431500.1280*
H3B0.420500.250000.256800.1280*
H4A0.051800.364900.066300.0980*
H4B0.219400.402900.024400.0980*
H60.384700.407300.032200.1090*
H70.546000.505500.215600.1130*
H9A0.360100.589900.424800.1800*
H9B0.201900.540100.500100.1800*
H9C0.100400.593100.364900.1800*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0858 (19)0.098 (2)0.0648 (18)0.0177 (16)0.0303 (14)0.0102 (15)
N10.070 (2)0.094 (2)0.0496 (19)0.0089 (16)0.0162 (14)0.0031 (17)
C10.050 (3)0.108 (5)0.048 (3)0.00000.008 (2)0.0000
C20.104 (3)0.107 (3)0.057 (3)0.013 (3)0.032 (2)0.000 (2)
C30.113 (5)0.148 (7)0.071 (4)0.00000.052 (4)0.0000
C40.085 (3)0.102 (3)0.058 (2)0.027 (2)0.013 (2)0.014 (2)
C50.085 (3)0.080 (3)0.057 (2)0.025 (2)0.025 (2)0.0179 (19)
C60.088 (3)0.101 (4)0.094 (4)0.021 (2)0.042 (3)0.017 (3)
C70.087 (3)0.102 (4)0.098 (4)0.003 (3)0.031 (3)0.018 (3)
C80.105 (3)0.086 (3)0.067 (3)0.005 (3)0.022 (2)0.020 (2)
C90.170 (6)0.112 (4)0.083 (4)0.004 (4)0.039 (4)0.000 (3)
P10.0552 (9)0.1200 (15)0.0645 (11)0.00000.0157 (7)0.0000
F10.104 (4)0.578 (18)0.065 (3)0.00000.030 (3)0.0000
F20.077 (3)0.516 (17)0.121 (5)0.00000.036 (3)0.0000
F30.111 (4)0.449 (14)0.094 (4)0.00000.023 (3)0.0000
F40.071 (3)0.59 (2)0.116 (5)0.00000.012 (3)0.0000
F50.291 (15)0.108 (6)0.199 (11)0.077 (8)0.013 (10)0.036 (6)
F60.242 (13)0.114 (7)0.36 (2)0.065 (7)0.111 (14)0.018 (9)
Geometric parameters (Å, º) top
P1—F6i1.469 (11)C5—C61.317 (7)
P1—F11.488 (5)C6—C71.407 (8)
P1—F21.510 (6)C7—C81.334 (8)
P1—F31.536 (6)C8—C91.487 (8)
P1—F41.508 (6)C1—H10.9300
P1—F51.474 (11)C2—H2B0.9700
P1—F61.469 (11)C2—H2A0.9700
P1—F5i1.474 (11)C3—H3A0.9700
F5—F61.29 (2)C3—H3B0.9700
O1—C51.372 (5)C4—H4A0.9700
O1—C81.379 (6)C4—H4B0.9700
N1—C21.459 (6)C6—H60.9300
N1—C41.474 (5)C7—H70.9300
N1—C11.299 (4)C9—H9C0.9600
C2—C31.491 (7)C9—H9A0.9600
C4—C51.467 (6)C9—H9B0.9600
F4—P1—F5i69.5 (7)N1—C4—C5113.8 (3)
F4—P1—F6i110.6 (7)O1—C5—C6110.2 (4)
F5—P1—F652.1 (9)C4—C5—C6133.1 (4)
F5—P1—F5i122.0 (8)O1—C5—C4116.7 (4)
F5—P1—F6i171.5 (8)C5—C6—C7107.4 (5)
F5i—P1—F6171.5 (8)C6—C7—C8107.2 (5)
F6—P1—F6i132.9 (9)O1—C8—C9115.4 (5)
F5i—P1—F6i52.1 (9)O1—C8—C7109.2 (4)
F2—P1—F5i111.4 (7)C7—C8—C9135.3 (6)
F2—P1—F6i69.0 (7)N1i—C1—H1117.00
F3—P1—F494.5 (4)N1—C1—H1117.00
F3—P1—F572.2 (5)N1—C2—H2A110.00
F1—P1—F290.9 (4)C3—C2—H2B110.00
F1—P1—F3178.9 (3)N1—C2—H2B110.00
F1—P1—F486.6 (4)C3—C2—H2A110.00
F1—P1—F5108.3 (5)H2A—C2—H2B108.00
F1—P1—F680.2 (7)C2i—C3—H3A109.00
F1—P1—F5i108.3 (5)C2—C3—H3A109.00
F1—P1—F6i80.2 (7)C2—C3—H3B109.00
F2—P1—F388.0 (4)H3A—C3—H3B108.00
F2—P1—F4177.5 (4)C2i—C3—H3B109.00
F2—P1—F5111.4 (7)N1—C4—H4B109.00
F2—P1—F669.0 (7)N1—C4—H4A109.00
F4—P1—F569.5 (7)H4A—C4—H4B108.00
F4—P1—F6110.6 (7)C5—C4—H4A109.00
F3—P1—F5i72.2 (5)C5—C4—H4B109.00
F3—P1—F6i99.4 (7)C5—C6—H6126.00
F3—P1—F699.4 (7)C7—C6—H6126.00
P1—F5—F663.7 (8)C8—C7—H7126.00
P1—F6—F564.2 (8)C6—C7—H7126.00
C5—O1—C8105.9 (3)H9B—C9—H9C110.00
C1—N1—C2120.1 (4)C8—C9—H9A109.00
C2—N1—C4119.4 (4)C8—C9—H9B110.00
C1—N1—C4120.5 (4)C8—C9—H9C109.00
N1—C1—N1i125.9 (4)H9A—C9—H9B109.00
N1—C2—C3109.6 (4)H9A—C9—H9C109.00
C2—C3—C2i111.9 (6)
F5i—P1—F5—F6172.5 (11)C2—N1—C1—N1i1.9 (7)
F1—P1—F6—F5122.5 (10)C1—N1—C4—C5121.5 (4)
F2—P1—F6—F5142.8 (11)C4—N1—C1—N1i180.0 (4)
F1—P1—F5—F661.1 (11)C2—N1—C4—C560.4 (5)
F2—P1—F5—F637.4 (11)C1—N1—C2—C325.1 (6)
F3—P1—F5—F6117.9 (11)C4—N1—C2—C3153.1 (5)
F4—P1—F5—F6140.1 (11)N1—C2—C3—C2i51.2 (7)
F3—P1—F6—F558.6 (10)N1—C4—C5—C696.4 (6)
F4—P1—F6—F539.9 (11)N1—C4—C5—O185.1 (4)
F6i—P1—F6—F5170.8 (12)C4—C5—C6—C7177.5 (5)
C5—O1—C8—C70.9 (5)O1—C5—C6—C71.1 (6)
C5—O1—C8—C9178.1 (4)C5—C6—C7—C81.7 (6)
C8—O1—C5—C4178.7 (4)C6—C7—C8—C9178.0 (6)
C8—O1—C5—C60.2 (5)C6—C7—C8—O11.6 (6)
Symmetry code: (i) x, y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···F2ii0.932.403.312 (8)167
C1—H1···F4iii0.932.523.044 (8)116
Symmetry codes: (ii) x, y, z1; (iii) x1, y, z1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···F2i0.932.403.312 (8)167
C1—H1···F4ii0.932.523.044 (8)116
Symmetry codes: (i) x, y, z1; (ii) x1, y, z1.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of a diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.

References

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