organic compounds
2,3-Bis{[2,3-dimethyl-6-(phenylvinyl)phenyl]imino}butane
aKey Laboratory of Eco-Environment-Related Polymer Materials of the Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: jianchaoyuan@nwnu.edu.cn
In the title compound, C36H36N2, a product of the condensation reaction of 2,3-dimethyl-6-phenylvinylbenzenamine and 2,3-butanedione, the complete molecule is generated by the application of an inversion centre. The central C—C bond in the 1,4-diazabutadiene fragment is trans-configured and situated about the inversion center. The dihedral angle between the ring attached to N and the 1,4-diazabutadiene plane is 78.24 (36)°, while the 1,4-diazabutadiene plane makes an angle of 30.71 (26)° with the phenyl ring.
CCDC reference: 980626
Related literature
The title compound was synthesized as an α-diimine ligand for transtion metals, see: Johnson et al. (1995); Gao et al. (2012); Zhang & Ye (2012); Sun et al. (2012); Popeney et al. (2012); Shi et al. (2012). For related structures, see: Helldörfer, Milius & Alt (2003); Helldörfer, Backhaus & Alt (2003); Popeney & Guan (2005); Kravchenko & Waymouth (1998).
Experimental
Crystal data
|
Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
Supporting information
CCDC reference: 980626
10.1107/S1600536814000440/qm2103sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814000440/qm2103Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536814000440/qm2103Isup3.cml
Formic acid (0.5 ml) was added to a stirred solution of 2,3-butanedione (0.09 g, 1.00 mmol) and 2,3-dimethyl-6-phenylvinylbenzenamine (0.49 g, 2.2 mmol) in ethanol (10 ml) (Fig. 2). The mixture was refluxed for 24 h, and then cooled and the precipitate was separated by filtration. The solid was recrystallized from EtOH/CH2Cl2 (v/v= 10:1), washed and dried under vacuum. Yield: 0.38 g (76%). Crystals suitable for X–raystructure determination were grown from a acyclohexane/dichloromethane (v:v= 1:2) solution. Anal. Calc. for C36H36N2: C, 86.35; H, 8.05; N, 5.59.Found: C,88.39; H, 8.09; N, 5.42.
All hydrogen atoms were placed in calculated positions with C—H distances of 0.93 Å and 0.96 Å for aryl and methyl H atoms. They were included in the
in a riding model approximation, respectively. The H atoms were assigned Uiso = 1.2Ueq(C) for aryl H and Uiso = 1.5Ueq(C) for methyl H.The discovery of Ni(II) and Pd(II) α-olefin polymerization catalysts containing a bulky α-diimine ligand, [MX2(α-diimine)](M=Ni,Pd;X=halide), by Brookhart and co-workers has stimulated renewed interest in the chemistry of 1,4-diazadiene ligands and their complexes (Johnson et al., 1995; Gao et al., 2012; Zhang et al., 2012; Sun et al., 2012; Popeney et al., 2012; Shi et al., 2012). The catalyst activity and properties of the resulting polymers are greatly dependent on the reaction conditions (Helldörfer et al., 2003) and ligand structure (Popeney et al., 2005; Helldörfer et al., 2003; Kravchenko & Waymouth, 1998). In this study, we designed and synthesized the title compound as a abidentate ligand (Fig. 1). The complete molecule is generated by the application of an inversion centre. The central C—C bond in the 1,4-diazabutadiene fragment is trans-configured and situated on an inversion center as shown in Fig. 1. Neither hydrogen bonding nor aromatic stacking are observed in the crystal structure.
The title compound was synthesized as an α-diimine ligand for transtion metals, see: Johnson et al. (1995); Gao et al. (2012); Zhang & Ye (2012); Sun et al. (2012); Popeney et al. (2012); Shi et al. (2012). For related structures, see: Helldörfer, Milius & Alt (2003); Helldörfer, Backhaus & Alt (2003); Popeney & Guan (2005); Kravchenko & Waymouth (1998).
Data collection: APEX2 (Bruker, 2008); cell
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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C36H36N2 | F(000) = 532 |
Mr = 496.67 | Dx = 1.116 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 9.613 (8) Å | Cell parameters from 1803 reflections |
b = 16.285 (14) Å | θ = 2.5–22.5° |
c = 9.639 (8) Å | µ = 0.06 mm−1 |
β = 101.679 (9)° | T = 296 K |
V = 1478 (2) Å3 | Block, yellow |
Z = 2 | 0.26 × 0.24 × 0.18 mm |
Bruker APEXII CCD diffractometer | 2693 independent reflections |
Radiation source: fine-focus sealed tube | 1374 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
φ and ω scans | θmax = 25.3°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | h = −11→11 |
Tmin = 0.984, Tmax = 0.989 | k = −19→19 |
10305 measured reflections | l = −11→10 |
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)] = 0.103 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.327 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.1098P)2 + 2.2955P] where P = (Fo2 + 2Fc2)/3 |
2693 reflections | (Δ/σ)max < 0.001 |
175 parameters | Δρmax = 0.46 e Å−3 |
84 restraints | Δρmin = −0.42 e Å−3 |
C36H36N2 | V = 1478 (2) Å3 |
Mr = 496.67 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.613 (8) Å | µ = 0.06 mm−1 |
b = 16.285 (14) Å | T = 296 K |
c = 9.639 (8) Å | 0.26 × 0.24 × 0.18 mm |
β = 101.679 (9)° |
Bruker APEXII CCD diffractometer | 2693 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | 1374 reflections with I > 2σ(I) |
Tmin = 0.984, Tmax = 0.989 | Rint = 0.041 |
10305 measured reflections |
R[F2 > 2σ(F2)] = 0.103 | 84 restraints |
wR(F2) = 0.327 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.46 e Å−3 |
2693 reflections | Δρmin = −0.42 e Å−3 |
175 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 | ||
C1 | 0.7542 (5) | 0.9715 (4) | 0.3661 (7) | 0.0873 (16) | |
C2 | 0.8434 (5) | 1.0392 (4) | 0.3706 (5) | 0.0738 (15) | |
C3 | 0.9406 (5) | 1.0398 (4) | 0.2810 (6) | 0.0795 (16) | |
C4 | 0.9452 (6) | 0.9752 (5) | 0.1928 (7) | 0.0954 (19) | |
H4 | 1.0072 | 0.9770 | 0.1303 | 0.114* | |
C5 | 0.8604 (7) | 0.9073 (5) | 0.1938 (8) | 0.107 (2) | |
H5 | 0.8682 | 0.8633 | 0.1344 | 0.128* | |
C6 | 0.7627 (6) | 0.9037 (4) | 0.2827 (9) | 0.112 (2) | |
C7 | 0.6752 (7) | 0.8283 (4) | 0.2878 (10) | 0.135 (2) | |
C8 | 0.7248 (9) | 0.7605 (5) | 0.3422 (13) | 0.175 (3) | |
H8A | 0.8211 | 0.7558 | 0.3819 | 0.210* | |
H8B | 0.6649 | 0.7157 | 0.3421 | 0.210* | |
C9 | 0.5196 (6) | 0.8376 (4) | 0.2159 (9) | 0.116 (2) | |
C10 | 0.4124 (7) | 0.8072 (4) | 0.2744 (8) | 0.108 (2) | |
H10 | 0.4340 | 0.7810 | 0.3619 | 0.130* | |
C11 | 0.2722 (7) | 0.8147 (5) | 0.2058 (9) | 0.110 (2) | |
H11 | 0.2004 | 0.7944 | 0.2481 | 0.132* | |
C12 | 0.2387 (7) | 0.8512 (4) | 0.0777 (8) | 0.101 (2) | |
H12 | 0.1442 | 0.8555 | 0.0313 | 0.121* | |
C13 | 0.3433 (7) | 0.8816 (5) | 0.0169 (7) | 0.109 (2) | |
H13 | 0.3207 | 0.9069 | −0.0713 | 0.131* | |
C14 | 0.4836 (7) | 0.8750 (4) | 0.0858 (8) | 0.107 (2) | |
H14 | 0.5547 | 0.8961 | 0.0436 | 0.128* | |
C15 | 0.8381 (7) | 1.1086 (4) | 0.4719 (7) | 0.107 (2) | |
H15A | 0.7756 | 1.1506 | 0.4254 | 0.160* | |
H15B | 0.9317 | 1.1309 | 0.5026 | 0.160* | |
H15C | 0.8038 | 1.0886 | 0.5524 | 0.160* | |
C16 | 1.0396 (6) | 1.1122 (4) | 0.2799 (7) | 0.109 (2) | |
H16A | 1.0944 | 1.1040 | 0.2081 | 0.163* | |
H16B | 1.1023 | 1.1168 | 0.3707 | 0.163* | |
H16C | 0.9848 | 1.1617 | 0.2601 | 0.163* | |
C17 | 0.5439 (5) | 1.0046 (4) | 0.4443 (6) | 0.0981 (17) | |
C18 | 0.4816 (6) | 1.0561 (5) | 0.3171 (7) | 0.114 (2) | |
H18A | 0.5390 | 1.0508 | 0.2468 | 0.171* | |
H18B | 0.4794 | 1.1126 | 0.3450 | 0.171* | |
H18C | 0.3868 | 1.0378 | 0.2783 | 0.171* | |
N1 | 0.6610 (4) | 0.9671 (3) | 0.4649 (5) | 0.0950 (14) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.049 (2) | 0.109 (4) | 0.104 (4) | 0.019 (3) | 0.016 (2) | 0.067 (3) |
C2 | 0.052 (3) | 0.095 (4) | 0.072 (3) | 0.016 (3) | 0.008 (2) | 0.035 (3) |
C3 | 0.051 (3) | 0.109 (4) | 0.077 (4) | 0.006 (3) | 0.010 (3) | 0.040 (3) |
C4 | 0.070 (4) | 0.131 (6) | 0.089 (4) | 0.020 (4) | 0.023 (3) | 0.024 (4) |
C5 | 0.077 (4) | 0.118 (6) | 0.120 (5) | 0.021 (4) | 0.005 (4) | 0.006 (4) |
C6 | 0.058 (3) | 0.089 (4) | 0.177 (5) | 0.011 (3) | −0.004 (3) | 0.057 (4) |
C7 | 0.081 (3) | 0.098 (3) | 0.207 (5) | 0.002 (3) | −0.021 (3) | 0.063 (3) |
C8 | 0.105 (5) | 0.098 (5) | 0.294 (9) | 0.008 (4) | −0.026 (6) | 0.051 (6) |
C9 | 0.070 (3) | 0.085 (4) | 0.180 (5) | −0.001 (3) | −0.007 (4) | 0.047 (4) |
C10 | 0.103 (5) | 0.104 (5) | 0.107 (5) | −0.026 (4) | −0.005 (4) | 0.017 (4) |
C11 | 0.092 (5) | 0.123 (6) | 0.115 (6) | −0.036 (4) | 0.022 (4) | −0.024 (5) |
C12 | 0.081 (4) | 0.129 (6) | 0.089 (5) | 0.007 (4) | 0.007 (4) | −0.030 (4) |
C13 | 0.088 (4) | 0.150 (6) | 0.085 (4) | 0.021 (4) | 0.011 (4) | 0.004 (4) |
C14 | 0.080 (4) | 0.119 (5) | 0.122 (5) | 0.017 (4) | 0.021 (4) | 0.030 (4) |
C15 | 0.100 (5) | 0.119 (5) | 0.103 (5) | 0.017 (4) | 0.023 (4) | 0.025 (4) |
C16 | 0.067 (3) | 0.142 (6) | 0.115 (5) | −0.011 (4) | 0.010 (3) | 0.050 (4) |
C17 | 0.058 (2) | 0.133 (4) | 0.107 (3) | 0.022 (3) | 0.026 (2) | 0.076 (3) |
C18 | 0.081 (4) | 0.159 (5) | 0.108 (4) | 0.036 (4) | 0.030 (3) | 0.082 (4) |
N1 | 0.054 (2) | 0.127 (3) | 0.107 (3) | 0.020 (2) | 0.024 (2) | 0.073 (2) |
C1—C6 | 1.379 (10) | C11—C12 | 1.350 (9) |
C1—C2 | 1.392 (8) | C11—H11 | 0.9300 |
C1—N1 | 1.435 (7) | C12—C13 | 1.356 (9) |
C2—C3 | 1.395 (7) | C12—H12 | 0.9300 |
C2—C15 | 1.500 (8) | C13—C14 | 1.381 (9) |
C3—C4 | 1.359 (9) | C13—H13 | 0.9300 |
C3—C16 | 1.516 (8) | C14—H14 | 0.9300 |
C4—C5 | 1.375 (9) | C15—H15A | 0.9600 |
C4—H4 | 0.9300 | C15—H15B | 0.9600 |
C5—C6 | 1.395 (9) | C15—H15C | 0.9600 |
C5—H5 | 0.9300 | C16—H16A | 0.9600 |
C6—C7 | 1.495 (9) | C16—H16B | 0.9600 |
C7—C8 | 1.273 (9) | C16—H16C | 0.9600 |
C7—C9 | 1.523 (9) | C17—N1 | 1.261 (6) |
C8—H8A | 0.9300 | C17—C17i | 1.502 (10) |
C8—H8B | 0.9300 | C17—C18 | 1.506 (7) |
C9—C10 | 1.364 (9) | C18—H18A | 0.9600 |
C9—C14 | 1.373 (9) | C18—H18B | 0.9600 |
C10—C11 | 1.381 (9) | C18—H18C | 0.9600 |
C10—H10 | 0.9300 | ||
C6—C1—C2 | 123.0 (5) | C10—C11—H11 | 119.8 |
C6—C1—N1 | 117.7 (6) | C11—C12—C13 | 119.7 (6) |
C2—C1—N1 | 118.8 (7) | C11—C12—H12 | 120.1 |
C1—C2—C3 | 118.2 (6) | C13—C12—H12 | 120.1 |
C1—C2—C15 | 121.0 (5) | C12—C13—C14 | 120.0 (7) |
C3—C2—C15 | 120.8 (6) | C12—C13—H13 | 120.0 |
C4—C3—C2 | 119.5 (6) | C14—C13—H13 | 120.0 |
C4—C3—C16 | 119.8 (6) | C9—C14—C13 | 121.0 (6) |
C2—C3—C16 | 120.7 (6) | C9—C14—H14 | 119.5 |
C3—C4—C5 | 121.6 (6) | C13—C14—H14 | 119.5 |
C3—C4—H4 | 119.2 | C2—C15—H15A | 109.5 |
C5—C4—H4 | 119.2 | C2—C15—H15B | 109.5 |
C4—C5—C6 | 120.8 (7) | H15A—C15—H15B | 109.5 |
C4—C5—H5 | 119.6 | C2—C15—H15C | 109.5 |
C6—C5—H5 | 119.6 | H15A—C15—H15C | 109.5 |
C1—C6—C5 | 116.8 (6) | H15B—C15—H15C | 109.5 |
C1—C6—C7 | 122.6 (8) | C3—C16—H16A | 109.5 |
C5—C6—C7 | 120.5 (9) | C3—C16—H16B | 109.5 |
C8—C7—C6 | 124.0 (6) | H16A—C16—H16B | 109.5 |
C8—C7—C9 | 121.7 (7) | C3—C16—H16C | 109.5 |
C6—C7—C9 | 114.3 (5) | H16A—C16—H16C | 109.5 |
C7—C8—H8A | 120.0 | H16B—C16—H16C | 109.5 |
C7—C8—H8B | 120.0 | N1—C17—C17i | 116.8 (5) |
H8A—C8—H8B | 120.0 | N1—C17—C18 | 126.4 (5) |
C10—C9—C14 | 117.8 (6) | C17i—C17—C18 | 116.7 (5) |
C10—C9—C7 | 122.0 (7) | C17—C18—H18A | 109.5 |
C14—C9—C7 | 120.1 (7) | C17—C18—H18B | 109.5 |
C9—C10—C11 | 121.0 (7) | H18A—C18—H18B | 109.5 |
C9—C10—H10 | 119.5 | C17—C18—H18C | 109.5 |
C11—C10—H10 | 119.5 | H18A—C18—H18C | 109.5 |
C12—C11—C10 | 120.4 (7) | H18B—C18—H18C | 109.5 |
C12—C11—H11 | 119.8 | C17—N1—C1 | 121.8 (4) |
C6—C1—C2—C3 | 3.4 (7) | C1—C6—C7—C9 | 74.5 (10) |
N1—C1—C2—C3 | 175.4 (4) | C5—C6—C7—C9 | −106.9 (8) |
C6—C1—C2—C15 | −174.9 (5) | C8—C7—C9—C10 | 44.8 (14) |
N1—C1—C2—C15 | −2.9 (7) | C6—C7—C9—C10 | −137.7 (8) |
C1—C2—C3—C4 | 0.1 (7) | C8—C7—C9—C14 | −132.8 (10) |
C15—C2—C3—C4 | 178.4 (5) | C6—C7—C9—C14 | 44.7 (12) |
C1—C2—C3—C16 | 179.4 (5) | C14—C9—C10—C11 | −0.8 (11) |
C15—C2—C3—C16 | −2.4 (7) | C7—C9—C10—C11 | −178.5 (7) |
C2—C3—C4—C5 | −2.9 (8) | C9—C10—C11—C12 | 1.1 (11) |
C16—C3—C4—C5 | 177.9 (5) | C10—C11—C12—C13 | −0.8 (11) |
C3—C4—C5—C6 | 2.2 (9) | C11—C12—C13—C14 | 0.1 (11) |
C2—C1—C6—C5 | −4.1 (8) | C10—C9—C14—C13 | 0.1 (11) |
N1—C1—C6—C5 | −176.1 (5) | C7—C9—C14—C13 | 177.9 (7) |
C2—C1—C6—C7 | 174.6 (5) | C12—C13—C14—C9 | 0.2 (11) |
N1—C1—C6—C7 | 2.5 (8) | C17i—C17—N1—C1 | −179.8 (7) |
C4—C5—C6—C1 | 1.3 (9) | C18—C17—N1—C1 | 1.9 (12) |
C4—C5—C6—C7 | −177.4 (6) | C6—C1—N1—C17 | −106.0 (7) |
C1—C6—C7—C8 | −108.0 (11) | C2—C1—N1—C17 | 81.6 (8) |
C5—C6—C7—C8 | 70.6 (13) |
Symmetry code: (i) −x+1, −y+2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C36H36N2 |
Mr | 496.67 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 9.613 (8), 16.285 (14), 9.639 (8) |
β (°) | 101.679 (9) |
V (Å3) | 1478 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.06 |
Crystal size (mm) | 0.26 × 0.24 × 0.18 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2008) |
Tmin, Tmax | 0.984, 0.989 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10305, 2693, 1374 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.601 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.103, 0.327, 1.03 |
No. of reflections | 2693 |
No. of parameters | 175 |
No. of restraints | 84 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.46, −0.42 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Acknowledgements
We thank the National Natural Science Foundation of China (20964003) and the National Natural Science Foundation of China (21364011) for funding. We also thank the Key Laboratory of Eco Environment-Related Polymer Materials of the Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province (Northwest Normal University), for financial support.
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The discovery of Ni(II) and Pd(II) α-olefin polymerization catalysts containing a bulky α-diimine ligand, [MX2(α-diimine)](M=Ni,Pd;X=halide), by Brookhart and co-workers has stimulated renewed interest in the chemistry of 1,4-diazadiene ligands and their complexes (Johnson et al., 1995; Gao et al., 2012; Zhang et al., 2012; Sun et al., 2012; Popeney et al., 2012; Shi et al., 2012). The catalyst activity and properties of the resulting polymers are greatly dependent on the reaction conditions (Helldörfer et al., 2003) and ligand structure (Popeney et al., 2005; Helldörfer et al., 2003; Kravchenko & Waymouth, 1998). In this study, we designed and synthesized the title compound as a abidentate ligand (Fig. 1). The complete molecule is generated by the application of an inversion centre. The central C—C bond in the 1,4-diazabutadiene fragment is trans-configured and situated on an inversion center as shown in Fig. 1. Neither hydrogen bonding nor aromatic stacking are observed in the crystal structure.