organic compounds
N,N-Bis(2-pyridylmethyl)-tert-butylamine
aSchool of Chemical and Physical Sciences, University of KwaZulu–Natal, Scottsville 3209, South Africa
*Correspondence e-mail: stewart@ukzn.ac.za
In the title compound, C16H21N3, the dihedral angle between the two pyridine rings is 88.11 (9)°. In the crystal, molecules are linked through intermolecular C—H⋯π interactions, forming a layer expanding parallel to the (10) plane.
Related literature
For related compounds, see: Mambanda et al. (2007); Foxon et al. (2007); Fujihara et al. (2004); Munro & Camp (2003). For metal complexes with the title compound as a ligand, see: Fujii et al. (2003); Lee & Lippard (2002); Mok et al. (1997). For the metal complex with N,N-bis(2-pyridylmethyl)ethylamine as a ligand, see: Pal et al. (1992).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536809001366/is2355sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809001366/is2355Isup2.hkl
The compound was synthesized following a literature method (Pal et al., 1992). Under a high flow of nitrogen, 6 ml of 20% NaOH solution was added to an aqueous solution of 2-picolyl chloridehydrochloride [(3.937 g (24 mmol) in 0.5 ml ultra pure water] to form a pink emulsion solution. 2-Amino-2-methyl propane (12 mmol) was added and the mixture stirred at 60°C. 40 ml of 20% NaOH solution was then added over a period of 1 h and the mixture left to stir for a further 12 h. The crude product was extracted with CHCl3 washed with ultra pure water and dried over Na2SO4. Excess solvent was removed under reduced pressure and the oil residue purified on a short chromatographic column packed with 0.5 g
and 5 g of neutral alumina using CHCl3 as an to afford a light yellow solution. Colourless single crystals suitable for X-ray diffraction were obtained from slow evaporation of the solvent from its solution made from a 5% chloroform in ethanol solution (yield: 1.73 g, 60%).Spectroscopic data: 1H NMR (400 MHz, CDCl3) δ / p.p.m.: 8.40 (d, 2H), 7.60 (t, 2H), 7.45 (d, 2H), 7.05 (t, 2H), 3.95 (s, 4H), 1.18 (s, 9H). 13C NMR (125 MHz, CDCl3) δ / p.p.m.: 27.0, 57.0, 122.0, 123.0,136.0, 148.0, 160. Anal. Calc. for C16H21N3: C 75.26, H 8.29, N 16.46; Found: C 74.89, H 7.97, N 17.37.
All Hydrogen atoms were positioned in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances in the range 0.93–0.97 Å, and with Uiso(H) = 1.2 or 1.5Ueq(C). In the absence of significant
effects, Friedel pairs have been merged.Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell
CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).C16H21N3 | F(000) = 552 |
Mr = 255.36 | Dx = 1.133 Mg m−3 |
Monoclinic, Cc | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: C -2yc | Cell parameters from 4672 reflections |
a = 6.1808 (3) Å | θ = 3.9–32.0° |
b = 17.9502 (8) Å | µ = 0.07 mm−1 |
c = 13.7079 (6) Å | T = 293 K |
β = 100.239 (4)° | Plate, colourless |
V = 1496.62 (12) Å3 | 0.50 × 0.50 × 0.30 mm |
Z = 4 |
Oxford Diffraction Xcalibur2 CCD diffractometer | 2392 independent reflections |
Radiation source: Enhance (Mo)X-Ray Source | 2024 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.012 |
Detector resolution: 8.4190 pixels mm-1 | θmax = 31.9°, θmin = 4.1° |
ω–2θ scans | h = −8→7 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | k = −26→26 |
Tmin = 0.967, Tmax = 0.980 | l = −18→20 |
7475 measured reflections |
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)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0873P)2 + 0.017P] where P = (Fo2 + 2Fc2)/3 |
2392 reflections | (Δ/σ)max = 0.001 |
175 parameters | Δρmax = 0.21 e Å−3 |
2 restraints | Δρmin = −0.22 e Å−3 |
0 constraints |
C16H21N3 | V = 1496.62 (12) Å3 |
Mr = 255.36 | Z = 4 |
Monoclinic, Cc | Mo Kα radiation |
a = 6.1808 (3) Å | µ = 0.07 mm−1 |
b = 17.9502 (8) Å | T = 293 K |
c = 13.7079 (6) Å | 0.50 × 0.50 × 0.30 mm |
β = 100.239 (4)° |
Oxford Diffraction Xcalibur2 CCD diffractometer | 2392 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | 2024 reflections with I > 2σ(I) |
Tmin = 0.967, Tmax = 0.980 | Rint = 0.012 |
7475 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 2 restraints |
wR(F2) = 0.119 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.21 e Å−3 |
2392 reflections | Δρmin = −0.22 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 | ||
C14 | 0.2251 (5) | 0.16330 (11) | 0.59751 (18) | 0.0645 (6) | |
H20 | 0.1452 | 0.1875 | 0.6425 | 0.097* | |
H21 | 0.2314 | 0.1955 | 0.5421 | 0.097* | |
H19 | 0.3716 | 0.1525 | 0.6311 | 0.097* | |
C15 | 0.2342 (5) | 0.05704 (14) | 0.48509 (17) | 0.0679 (6) | |
H18 | 0.3767 | 0.0409 | 0.5180 | 0.102* | |
H16 | 0.2508 | 0.0937 | 0.4359 | 0.102* | |
H17 | 0.1537 | 0.0152 | 0.4537 | 0.102* | |
C16 | −0.1269 (5) | 0.10773 (16) | 0.5103 (2) | 0.0739 (7) | |
H15 | −0.1940 | 0.0630 | 0.4806 | 0.111* | |
H14 | −0.1260 | 0.1449 | 0.4600 | 0.111* | |
H13 | −0.2090 | 0.1258 | 0.5586 | 0.111* | |
N3 | 0.1632 (2) | 0.14031 (8) | 0.88126 (11) | 0.0448 (3) | |
C9 | 0.2329 (2) | 0.09809 (8) | 0.81277 (11) | 0.0365 (3) | |
N1 | 0.1221 (2) | 0.03781 (7) | 0.64559 (9) | 0.0382 (3) | |
C3 | 0.1172 (3) | −0.09657 (8) | 0.68278 (12) | 0.0384 (3) | |
C10 | 0.4530 (3) | 0.08012 (10) | 0.81845 (13) | 0.0434 (3) | |
H8 | 0.4982 | 0.0513 | 0.7694 | 0.052* | |
C1 | 0.1094 (3) | 0.09104 (10) | 0.56073 (13) | 0.0455 (4) | |
C2 | 0.0134 (3) | −0.03384 (10) | 0.61861 (13) | 0.0452 (4) | |
H11 | 0.0200 | −0.0449 | 0.5499 | 0.054* | |
H12 | −0.1403 | −0.0300 | 0.6245 | 0.054* | |
N2 | −0.0196 (2) | −0.14516 (8) | 0.71406 (13) | 0.0476 (3) | |
C8 | 0.0527 (3) | 0.06774 (11) | 0.73393 (12) | 0.0442 (4) | |
H9 | −0.0232 | 0.0287 | 0.7633 | 0.053* | |
H10 | −0.0527 | 0.1073 | 0.7137 | 0.053* | |
C12 | 0.5344 (3) | 0.14791 (10) | 0.96934 (14) | 0.0529 (4) | |
H6 | 0.6329 | 0.1652 | 1.0240 | 0.063* | |
C11 | 0.6047 (3) | 0.10564 (11) | 0.89812 (15) | 0.0501 (4) | |
H7 | 0.7530 | 0.0941 | 0.9031 | 0.060* | |
C4 | 0.3437 (3) | −0.10609 (10) | 0.70322 (14) | 0.0466 (4) | |
H4 | 0.4352 | −0.0713 | 0.6809 | 0.056* | |
C13 | 0.3140 (4) | 0.16421 (10) | 0.95790 (14) | 0.0519 (4) | |
H5 | 0.2664 | 0.1935 | 1.0060 | 0.062* | |
C5 | 0.4322 (3) | −0.16716 (12) | 0.75666 (16) | 0.0553 (5) | |
H3 | 0.5836 | −0.1743 | 0.7708 | 0.066* | |
C6 | 0.2920 (4) | −0.21757 (11) | 0.78883 (17) | 0.0567 (5) | |
H2 | 0.3460 | −0.2594 | 0.8252 | 0.068* | |
C7 | 0.0701 (3) | −0.20409 (10) | 0.76555 (17) | 0.0554 (5) | |
H1 | −0.0242 | −0.2383 | 0.7871 | 0.066* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C14 | 0.0927 (17) | 0.0403 (9) | 0.0584 (12) | −0.0074 (10) | 0.0077 (11) | 0.0060 (8) |
C15 | 0.0990 (18) | 0.0620 (12) | 0.0486 (11) | −0.0019 (12) | 0.0296 (11) | 0.0014 (9) |
C16 | 0.0720 (14) | 0.0773 (16) | 0.0638 (13) | 0.0155 (12) | −0.0114 (11) | 0.0176 (11) |
N3 | 0.0476 (8) | 0.0460 (7) | 0.0408 (7) | 0.0030 (6) | 0.0075 (6) | −0.0021 (5) |
C9 | 0.0370 (7) | 0.0395 (7) | 0.0324 (6) | −0.0014 (5) | 0.0047 (5) | 0.0033 (5) |
N1 | 0.0426 (7) | 0.0397 (6) | 0.0307 (6) | −0.0034 (5) | 0.0021 (5) | 0.0008 (4) |
C3 | 0.0404 (8) | 0.0389 (7) | 0.0347 (7) | −0.0029 (6) | 0.0033 (5) | −0.0005 (5) |
C10 | 0.0369 (7) | 0.0529 (9) | 0.0396 (7) | 0.0002 (6) | 0.0044 (6) | −0.0019 (6) |
C1 | 0.0559 (10) | 0.0416 (8) | 0.0371 (7) | 0.0006 (6) | 0.0034 (7) | 0.0054 (6) |
C2 | 0.0446 (8) | 0.0451 (8) | 0.0409 (8) | −0.0067 (6) | −0.0060 (6) | 0.0039 (6) |
N2 | 0.0412 (7) | 0.0437 (7) | 0.0568 (9) | −0.0058 (6) | 0.0056 (6) | 0.0045 (6) |
C8 | 0.0342 (7) | 0.0603 (10) | 0.0369 (7) | −0.0018 (6) | 0.0031 (6) | −0.0030 (6) |
C12 | 0.0612 (11) | 0.0493 (9) | 0.0427 (9) | −0.0136 (8) | −0.0054 (8) | 0.0022 (7) |
C11 | 0.0403 (8) | 0.0573 (10) | 0.0493 (9) | −0.0036 (7) | −0.0013 (7) | 0.0072 (7) |
C4 | 0.0371 (8) | 0.0526 (9) | 0.0514 (9) | −0.0026 (6) | 0.0114 (7) | 0.0003 (7) |
C13 | 0.0678 (11) | 0.0456 (8) | 0.0413 (9) | −0.0018 (8) | 0.0071 (8) | −0.0066 (7) |
C5 | 0.0433 (9) | 0.0576 (10) | 0.0637 (12) | 0.0114 (8) | 0.0061 (8) | −0.0027 (9) |
C6 | 0.0618 (11) | 0.0419 (8) | 0.0640 (11) | 0.0110 (7) | 0.0043 (9) | 0.0033 (8) |
C7 | 0.0539 (10) | 0.0426 (9) | 0.0702 (12) | −0.0057 (7) | 0.0127 (9) | 0.0088 (8) |
C14—C1 | 1.523 (3) | C3—C2 | 1.501 (2) |
C14—H20 | 0.9600 | C10—C11 | 1.385 (2) |
C14—H21 | 0.9600 | C10—H8 | 0.9300 |
C14—H19 | 0.9600 | C2—H11 | 0.9700 |
C15—C1 | 1.525 (3) | C2—H12 | 0.9700 |
C15—H18 | 0.9600 | N2—C7 | 1.336 (2) |
C15—H16 | 0.9600 | C8—H9 | 0.9700 |
C15—H17 | 0.9600 | C8—H10 | 0.9700 |
C16—C1 | 1.531 (3) | C12—C11 | 1.367 (3) |
C16—H15 | 0.9600 | C12—C13 | 1.375 (3) |
C16—H14 | 0.9600 | C12—H6 | 0.9300 |
C16—H13 | 0.9600 | C11—H7 | 0.9300 |
N3—C9 | 1.336 (2) | C4—C5 | 1.377 (3) |
N3—C13 | 1.345 (2) | C4—H4 | 0.9300 |
C9—C10 | 1.387 (2) | C13—H5 | 0.9300 |
C9—C8 | 1.509 (2) | C5—C6 | 1.378 (3) |
N1—C8 | 1.457 (2) | C5—H3 | 0.9300 |
N1—C2 | 1.468 (2) | C6—C7 | 1.374 (3) |
N1—C1 | 1.497 (2) | C6—H2 | 0.9300 |
C3—N2 | 1.338 (2) | C7—H1 | 0.9300 |
C3—C4 | 1.388 (2) | ||
C1—C14—H20 | 109.5 | C15—C1—C16 | 109.18 (19) |
C1—C14—H21 | 109.5 | N1—C2—C3 | 112.38 (12) |
H20—C14—H21 | 109.5 | N1—C2—H11 | 109.1 |
C1—C14—H19 | 109.5 | C3—C2—H11 | 109.1 |
H20—C14—H19 | 109.5 | N1—C2—H12 | 109.1 |
H21—C14—H19 | 109.5 | C3—C2—H12 | 109.1 |
C1—C15—H18 | 109.5 | H11—C2—H12 | 107.9 |
C1—C15—H16 | 109.5 | C7—N2—C3 | 117.31 (16) |
H18—C15—H16 | 109.5 | N1—C8—C9 | 116.05 (14) |
C1—C15—H17 | 109.5 | N1—C8—H9 | 108.3 |
H18—C15—H17 | 109.5 | C9—C8—H9 | 108.3 |
H16—C15—H17 | 109.5 | N1—C8—H10 | 108.3 |
C1—C16—H15 | 109.5 | C9—C8—H10 | 108.3 |
C1—C16—H14 | 109.5 | H9—C8—H10 | 107.4 |
H15—C16—H14 | 109.5 | C11—C12—C13 | 118.10 (17) |
C1—C16—H13 | 109.5 | C11—C12—H6 | 121.0 |
H15—C16—H13 | 109.5 | C13—C12—H6 | 121.0 |
H14—C16—H13 | 109.5 | C12—C11—C10 | 119.36 (17) |
C9—N3—C13 | 117.70 (16) | C12—C11—H7 | 120.3 |
N3—C9—C10 | 121.88 (15) | C10—C11—H7 | 120.3 |
N3—C9—C8 | 114.75 (14) | C5—C4—C3 | 119.78 (16) |
C10—C9—C8 | 123.24 (14) | C5—C4—H4 | 120.1 |
C8—N1—C2 | 110.06 (14) | C3—C4—H4 | 120.1 |
C8—N1—C1 | 115.35 (14) | N3—C13—C12 | 123.79 (17) |
C2—N1—C1 | 113.90 (12) | N3—C13—H5 | 118.1 |
N2—C3—C4 | 121.83 (15) | C12—C13—H5 | 118.1 |
N2—C3—C2 | 116.63 (15) | C4—C5—C6 | 118.68 (17) |
C4—C3—C2 | 121.42 (15) | C4—C5—H3 | 120.7 |
C11—C10—C9 | 119.16 (17) | C6—C5—H3 | 120.7 |
C11—C10—H8 | 120.4 | C7—C6—C5 | 117.95 (18) |
C9—C10—H8 | 120.4 | C7—C6—H2 | 121.0 |
N1—C1—C14 | 109.25 (14) | C5—C6—H2 | 121.0 |
N1—C1—C15 | 108.06 (15) | N2—C7—C6 | 124.45 (18) |
C14—C1—C15 | 107.53 (19) | N2—C7—H1 | 117.8 |
N1—C1—C16 | 112.96 (17) | C6—C7—H1 | 117.8 |
C14—C1—C16 | 109.70 (18) | ||
C13—N3—C9—C10 | −1.1 (2) | C2—C3—N2—C7 | 175.54 (17) |
C13—N3—C9—C8 | 174.86 (16) | C2—N1—C8—C9 | 134.62 (15) |
N3—C9—C10—C11 | 1.0 (2) | C1—N1—C8—C9 | −94.82 (18) |
C8—C9—C10—C11 | −174.62 (17) | N3—C9—C8—N1 | 165.09 (14) |
C8—N1—C1—C14 | 50.8 (2) | C10—C9—C8—N1 | −19.0 (2) |
C2—N1—C1—C14 | 179.45 (17) | C13—C12—C11—C10 | −0.8 (3) |
C8—N1—C1—C15 | 167.47 (17) | C9—C10—C11—C12 | 0.0 (3) |
C2—N1—C1—C15 | −63.8 (2) | N2—C3—C4—C5 | 0.3 (3) |
C8—N1—C1—C16 | −71.6 (2) | C2—C3—C4—C5 | −175.51 (17) |
C2—N1—C1—C16 | 57.1 (2) | C9—N3—C13—C12 | 0.3 (3) |
C8—N1—C2—C3 | −77.86 (18) | C11—C12—C13—N3 | 0.7 (3) |
C1—N1—C2—C3 | 150.82 (15) | C3—C4—C5—C6 | −0.1 (3) |
N2—C3—C2—N1 | 137.29 (16) | C4—C5—C6—C7 | 0.1 (3) |
C4—C3—C2—N1 | −46.7 (2) | C3—N2—C7—C6 | 0.5 (3) |
C4—C3—N2—C7 | −0.5 (3) | C5—C6—C7—N2 | −0.3 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C7—H1···Cg2i | 0.93 | 2.97 | 3.819 (2) | 153 |
C15—H16···Cg1ii | 0.96 | 2.94 | 3.836 (2) | 156 |
Symmetry codes: (i) x−1/2, y−1/2, z; (ii) x, −y, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C16H21N3 |
Mr | 255.36 |
Crystal system, space group | Monoclinic, Cc |
Temperature (K) | 293 |
a, b, c (Å) | 6.1808 (3), 17.9502 (8), 13.7079 (6) |
β (°) | 100.239 (4) |
V (Å3) | 1496.62 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.50 × 0.50 × 0.30 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur2 CCD diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2008) |
Tmin, Tmax | 0.967, 0.980 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7475, 2392, 2024 |
Rint | 0.012 |
(sin θ/λ)max (Å−1) | 0.743 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.119, 1.02 |
No. of reflections | 2392 |
No. of parameters | 175 |
No. of restraints | 2 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.22 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2008), CrysAlis RED (Oxford Diffraction, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
C7—H1···Cg2i | 0.93 | 2.97 | 3.819 (2) | 153 |
C15—H16···Cg1ii | 0.96 | 2.94 | 3.836 (2) | 156 |
Symmetry codes: (i) x−1/2, y−1/2, z; (ii) x, −y, z−1/2. |
Acknowledgements
The authors gratefully acknowledge financial support from the University of Kwazulu-Natal and the South African National Research Foundation. We thank Mr C. Grimmer for the NMR analysis of the samples. We also thank Professor O. Q Munro and Professor J. Field for their guidance.
References
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Foxon, S., Xu, J., Turba, S., Leibold, M., Hampel, F., Walter, O., Wurtele, C., Holthausen, M. & Schindler, S. (2007). Eur. J. Inorg. Chem. pp. 423–443. Google Scholar
Fujihara, T., Saito, M. & Nagasawa, A. (2004). Acta Cryst. E60, o262–o263. Web of Science CSD CrossRef IUCr Journals Google Scholar
Fujii, T., Naito, A., Yamaguchi, S., Wada, A., Funahashi, Y., Jitsukawa, K., Nagatomo, S., Kitagawa, T. & Masuda, H. (2003). Chem. Commun. pp. 2700–2701. Web of Science CSD CrossRef Google Scholar
Lee, D. & Lippard, S. J. (2002). Inorg. Chim. Acta, 341, 1–11. Web of Science CSD CrossRef CAS Google Scholar
Mambanda, A., Jaganyi, D. & Munro, O. Q. (2007). Acta Cryst. C63, o676–o680. Web of Science CSD CrossRef IUCr Journals Google Scholar
Mok, H. J., Davis, J. A., Pal, S., Mandal, S. K. & Armstrong, W. H. (1997). Inorg. Chim. Acta, 263, 385–394. CSD CrossRef CAS Web of Science Google Scholar
Munro, O. Q. & Camp, G. L. (2003). Acta Cryst. C59, o672–o675. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England. Google Scholar
Pal, S., Chan, M. K. & Armstrong, W. H. (1992). J. Am. Chem. Soc. 114, 6398–6404. CSD CrossRef CAS Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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The title compound is a versatile tridentate N-donor ligand, and it (Fujii et al., 2003; Lee & Lippard, 2002; Mok et al., 1997) and its analogue, N, N-bis(2-pyridylmethyl)ethylamine (Pal et al., 1992) have been used extensively in metal coordination. The related crystal structures of symmetrical bis(tridentate) ligands have been reportd (Mambanda et al., 2007; Foxon et al., 2007; Fujihara et al., 2004).
The crystal structure of the title compound (Fig. 1) shows that the three nitrogen atoms (one sp3 and two pyridine sp2) are not suitability orientated for pincer-like coordination to a metal. Rotation about the C2—C3 and C8—C9 bonds are required for that to occur. The relative orientation of the two pyridine rings is reflected in a dihedral angle between their mean planes of 88.11 (9)°, clearly this angle would have to change were the ligand to bind to a metal centre. The steric influence of the bulky tert-butyl group is reflected in the C1—N1—C2 and C1—N1—C8 angles [113.90 (13) and 115.34 (13)°, respectively], being larger than the C2—N1—C8 angle of 110.08 (13)°. The methylene groups of the structure all adopt the expected staggered (lowest energy) conformation (Munro & Camp, 2003). The pyridyl ring containing atom N2 is orientated at 18 (1)° relative to the mean plane of the N-tert-butyl group (plane through C16—C1—N1), whilst that containing N3 is orientated at 74 (1)°.
There are no short van der Waals contacts less than the sum of the van der Waals radii in this system, reflected in the loose packing, however weak (possibly stabilizing) C—H···π intermolecular interactions do occur. The metrics of such interactions reflect a T-shaped, edge-to-face geometry. Specifically, let us define Cg1 as the centre of gravity of the pyridyl N2/C3–C7 ring and Cg2 the centre of gravity of the pyridyl N3/C9–C13 ring. A C—H···π interaction with a separation of 2.97 (1) Å exists between C7—H1 from the pyridyl ring containing atom N2 and Cg2 of neighbouring symmetry related molecule [symmetry code: (i) x - 1/2, y - 1/2, z] (Table 1). A similar C—H···π interaction with a separation of 2.94 (1) Å exists between C15—H16 from one of the methyl groups of the tert-butyl moiety and Cg1 on the symmetry related neighbouring molecule with symmetry code: (ii) x, -y, z - 1/2. Figure 2 shows the packing within the unit cell for the title compound.