organic compounds
1,3,5-Tris(4-methoxyphenyl)-1,3,5-triazinane-2,4,6-trione
aThe School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, People's Republic of China
*Correspondence e-mail: fangli@sxu.edu.cn
The complete molecule of the title compound, C24H21N3O6, is generated by the application of threefold rotation symmetry about an axis perpendicular to the central ring. The molecule exhibits a propeller-like shape. The dihedral angle between each benzene ring and the heterocyclic ring is 74.0 (1)°. The molecules pack with no specific intermolecular interactions between them. The SQUEEZE procedure in PLATON [Spek (2009). Acta Cryst. D65, 148–155] was used to model disordered solvent molecules, presumed to be acetone; the calculated unit-cell data do not take into account the presence of these.
CCDC reference: 979026
Related literature
For general background to trimerization of aromatic isocyanates, see: Raders & Verkade (2010); Duong et al. (2004); Tang et al. (1994); Zhitinkina et al. (1985); Nawata et al. (1975); Nicholas & Gmitter (1965).
Experimental
Crystal data
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Data collection: SMART (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
CCDC reference: 979026
10.1107/S160053681303482X/tk5284sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681303482X/tk5284Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681303482X/tk5284Isup3.cml
To a stirred solution of lithium dibenzylamide (0.04 g) in diethyl ether was added 4-methoxyphenyl isothiocyanate (29.8 g). After stirring for 2 min, the mixture afforded a white precipitate. The resulting precipitate was collected by suction filtration and recrystallized from acetone to obtain white crystals of 1,3,5-tris-(4-methoxyphenyl)-1,3,5-triazinane-2,4,6-trione (yield: 90%), m.p. 530–531 K.
The H atoms were placed in their idealised positions with C—H = 0.95–0.98 Å, and refined as riding with Uiso(H) = 1.2–1.5Ueq. The structure contains solvent accessible voids of 153 A3. The SQUEEZE procedure in PLATON (Spek, 2009) was used to model the disordered solvent molecules, presumed to be 4–6 acetone molecules per unit cell.
Trimerization of aromatic isocyanates, manufactured by cyclotrimerizing corresponding isocyanates, has been known to enhance the properties of polyurethanes or coating materials (Raders & Verkade, 2010; Duong et al., 2004; Tang et al., 1994; Zhitinkina et al., 1985; Nawata et al., 1975; Nicholas & Gmitter, 1965). Polymers, such as polyurethanes incorporated with isocyanurates, have enhanced
flame retardation, chemical resistance and film-forming characteristics. Isocyanurates are also used in the synthesis of co-polymer resins to improve their water-resistance, transparency and impact resistance. During research on the properties of lithium dibenzylamide, a simple and efficient catalyst for isocyanate cyclotrimerization to isocyanurate, we obtained crystals of 1,3,5-tris-(4-methoxyphenyl)-1,3,5-triazinane-2,4,6-trione.In the title compound, C24H21N3O6, the six-membered heterocyclic ring lies on a threefold rotation axis and adopts a planar conformation. The molecule exhibits a propeller-like shape. The dihedral angle between each benzene ring and the heterocyclic ring is 74.0 (1).
Trimerization of aromatic isocyanates, manufactured by cyclotrimerizing corresponding isocyanates, has been known to enhance the properties of polyurethanes or coating materials (Raders & Verkade, 2010; Duong et al., 2004; Tang et al., 1994; Zhitinkina et al., 1985; Nawata et al., 1975; Nicholas & Gmitter, 1965). Polymers, such as polyurethanes incorporated with isocyanurates, have enhanced
flame retardation, chemical resistance and film-forming characteristics. Isocyanurates are also used in the synthesis of co-polymer resins to improve their water-resistance, transparency and impact resistance. During research on the properties of lithium dibenzylamide, a simple and efficient catalyst for isocyanate cyclotrimerization to isocyanurate, we obtained crystals of 1,3,5-tris-(4-methoxyphenyl)-1,3,5-triazinane-2,4,6-trione.In the title compound, C24H21N3O6, the six-membered heterocyclic ring lies on a threefold rotation axis and adopts a planar conformation. The molecule exhibits a propeller-like shape. The dihedral angle between each benzene ring and the heterocyclic ring is 74.0 (1).
For general background to trimerization of aromatic
see: Raders & Verkade (2010); Duong et al. (2004); Tang et al. (1994); Zhitinkina et al. (1985); Nawata et al. (1975); Nicholas & Gmitter (1965).To a stirred solution of lithium dibenzylamide (0.04 g) in diethyl ether was added 4-methoxyphenyl isothiocyanate (29.8 g). After stirring for 2 min, the mixture afforded a white precipitate. The resulting precipitate was collected by suction filtration and recrystallized from acetone to obtain white crystals of 1,3,5-tris-(4-methoxyphenyl)-1,3,5-triazinane-2,4,6-trione (yield: 90%), m.p. 530–531 K.
detailsThe H atoms were placed in their idealised positions with C—H = 0.95–0.98 Å, and refined as riding with Uiso(H) = 1.2–1.5Ueq. The structure contains solvent accessible voids of 153 A3. The SQUEEZE procedure in PLATON (Spek, 2009) was used to model the disordered solvent molecules, presumed to be 4–6 acetone molecules per unit cell.
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).Fig. 1. Molecular structure of I showing 30% probability displacement ellipsoids. The hydrogen atoms are omitted for clarity. |
C24H21N3O6 | Dx = 1.107 Mg m−3 |
Mr = 447.44 | Mo Kα radiation, λ = 0.71073 Å |
Trigonal, R3c | Cell parameters from 1247 reflections |
Hall symbol: R 3 -2"c | θ = 2.3–20.4° |
a = 13.2008 (14) Å | µ = 0.08 mm−1 |
c = 26.695 (3) Å | T = 200 K |
V = 4028.7 (8) Å3 | Block, colourless |
Z = 6 | 0.51 × 0.49 × 0.04 mm |
F(000) = 1404 |
Bruker SMART CCD area-detector diffractometer | 1577 independent reflections |
Radiation source: fine-focus sealed tube | 1142 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.031 |
phi and ω scans | θmax = 25.0°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→15 |
Tmin = 0.960, Tmax = 0.997 | k = −15→14 |
6995 measured reflections | l = −31→31 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.044 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.122 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0687P)2] where P = (Fo2 + 2Fc2)/3 |
1577 reflections | (Δ/σ)max = 0.001 |
101 parameters | Δρmax = 0.16 e Å−3 |
1 restraint | Δρmin = −0.12 e Å−3 |
C24H21N3O6 | Z = 6 |
Mr = 447.44 | Mo Kα radiation |
Trigonal, R3c | µ = 0.08 mm−1 |
a = 13.2008 (14) Å | T = 200 K |
c = 26.695 (3) Å | 0.51 × 0.49 × 0.04 mm |
V = 4028.7 (8) Å3 |
Bruker SMART CCD area-detector diffractometer | 1577 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1142 reflections with I > 2σ(I) |
Tmin = 0.960, Tmax = 0.997 | Rint = 0.031 |
6995 measured reflections |
R[F2 > 2σ(F2)] = 0.044 | 1 restraint |
wR(F2) = 0.122 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.16 e Å−3 |
1577 reflections | Δρmin = −0.12 e Å−3 |
101 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.24317 (15) | 0.68853 (16) | 0.06336 (8) | 0.0507 (6) | |
O1 | 0.37628 (17) | 0.88360 (16) | 0.06161 (9) | 0.0710 (6) | |
O2 | −0.1275 (2) | 0.7774 (3) | 0.06263 (12) | 0.1146 (9) | |
C1 | 0.1470 (2) | 0.7108 (2) | 0.06541 (11) | 0.0552 (7) | |
C2 | 0.0864 (2) | 0.6942 (2) | 0.10907 (12) | 0.0652 (7) | |
H2 | 0.1090 | 0.6709 | 0.1387 | 0.078* | |
C3 | −0.0104 (3) | 0.7124 (3) | 0.10944 (13) | 0.0768 (9) | |
H3 | −0.0565 | 0.6970 | 0.1388 | 0.092* | |
C4 | −0.0369 (2) | 0.7525 (3) | 0.06691 (14) | 0.0724 (8) | |
C5 | 0.0253 (3) | 0.7708 (3) | 0.02514 (15) | 0.0878 (10) | |
H5 | 0.0050 | 0.7983 | −0.0039 | 0.105* | |
C6 | 0.1168 (3) | 0.7514 (3) | 0.02308 (12) | 0.0729 (8) | |
H6 | 0.1600 | 0.7654 | −0.0071 | 0.088* | |
C7 | 0.3566 (2) | 0.7838 (2) | 0.06225 (11) | 0.0566 (7) | |
C8 | −0.2060 (4) | 0.7446 (5) | 0.1028 (2) | 0.1312 (17) | |
H8A | −0.2414 | 0.6604 | 0.1087 | 0.197* | |
H8B | −0.2674 | 0.7631 | 0.0948 | 0.197* | |
H8C | −0.1641 | 0.7874 | 0.1329 | 0.197* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0390 (12) | 0.0406 (12) | 0.0734 (15) | 0.0206 (10) | 0.0029 (11) | 0.0033 (11) |
O1 | 0.0571 (12) | 0.0488 (12) | 0.1124 (15) | 0.0306 (10) | −0.0006 (11) | −0.0036 (10) |
O2 | 0.0943 (19) | 0.158 (3) | 0.127 (2) | 0.0896 (19) | 0.0056 (17) | 0.0234 (18) |
C1 | 0.0452 (16) | 0.0456 (15) | 0.0770 (18) | 0.0242 (14) | 0.0011 (15) | −0.0026 (14) |
C2 | 0.0608 (17) | 0.0636 (18) | 0.0762 (19) | 0.0350 (14) | 0.0076 (14) | 0.0051 (15) |
C3 | 0.0591 (18) | 0.080 (2) | 0.089 (2) | 0.0331 (16) | 0.0207 (15) | 0.0075 (17) |
C4 | 0.0538 (16) | 0.078 (2) | 0.098 (2) | 0.0429 (16) | −0.0027 (18) | 0.0036 (17) |
C5 | 0.071 (2) | 0.111 (3) | 0.093 (3) | 0.054 (2) | −0.008 (2) | 0.0187 (19) |
C6 | 0.0654 (19) | 0.079 (2) | 0.081 (2) | 0.0410 (16) | 0.0038 (16) | 0.0179 (16) |
C7 | 0.0465 (16) | 0.0472 (16) | 0.0751 (19) | 0.0227 (11) | 0.0012 (14) | −0.0021 (14) |
C8 | 0.085 (3) | 0.174 (4) | 0.166 (4) | 0.088 (3) | 0.016 (3) | −0.011 (4) |
N1—C7i | 1.384 (3) | C3—C4 | 1.370 (5) |
N1—C7 | 1.393 (3) | C3—H3 | 0.9500 |
N1—C1 | 1.440 (3) | C4—C5 | 1.333 (4) |
O1—C7 | 1.209 (3) | C5—C6 | 1.356 (4) |
O2—C4 | 1.395 (4) | C5—H5 | 0.9500 |
O2—C8 | 1.400 (5) | C6—H6 | 0.9500 |
C1—C2 | 1.368 (4) | C7—N1ii | 1.384 (3) |
C1—C6 | 1.392 (4) | C8—H8A | 0.9800 |
C2—C3 | 1.413 (4) | C8—H8B | 0.9800 |
C2—H2 | 0.9500 | C8—H8C | 0.9800 |
C7i—N1—C7 | 124.2 (3) | C4—C5—C6 | 121.7 (3) |
C7i—N1—C1 | 117.35 (19) | C4—C5—H5 | 119.2 |
C7—N1—C1 | 118.43 (19) | C6—C5—H5 | 119.2 |
C4—O2—C8 | 117.0 (3) | C5—C6—C1 | 119.6 (3) |
C2—C1—C6 | 119.7 (2) | C5—C6—H6 | 120.2 |
C2—C1—N1 | 120.3 (3) | C1—C6—H6 | 120.2 |
C6—C1—N1 | 120.0 (2) | O1—C7—N1ii | 122.2 (2) |
C1—C2—C3 | 119.1 (3) | O1—C7—N1 | 122.1 (2) |
C1—C2—H2 | 120.5 | N1ii—C7—N1 | 115.7 (3) |
C3—C2—H2 | 120.5 | O2—C8—H8A | 109.5 |
C4—C3—C2 | 119.1 (3) | O2—C8—H8B | 109.5 |
C4—C3—H3 | 120.4 | H8A—C8—H8B | 109.5 |
C2—C3—H3 | 120.4 | O2—C8—H8C | 109.5 |
C5—C4—C3 | 120.7 (3) | H8A—C8—H8C | 109.5 |
C5—C4—O2 | 114.3 (3) | H8B—C8—H8C | 109.5 |
C3—C4—O2 | 125.0 (3) |
Symmetry codes: (i) −y+1, x−y+1, z; (ii) −x+y, −x+1, z. |
Experimental details
Crystal data | |
Chemical formula | C24H21N3O6 |
Mr | 447.44 |
Crystal system, space group | Trigonal, R3c |
Temperature (K) | 200 |
a, c (Å) | 13.2008 (14), 26.695 (3) |
V (Å3) | 4028.7 (8) |
Z | 6 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.51 × 0.49 × 0.04 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.960, 0.997 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6995, 1577, 1142 |
Rint | 0.031 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.122, 1.05 |
No. of reflections | 1577 |
No. of parameters | 101 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.16, −0.12 |
Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
Acknowledgements
We thank the SXNSFC (2011021011–1) for financial support.
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