Acta Cryst. (2008). E64, o1715 [ doi:10.1107/S1600536808024719 ]
The structure of the title compound, C18H18N4O·CH2Cl2, was solved using data collected from a multiple crystal (note high R factors). The crystal structure is dominated by two bifurcated attractive C-H
N(cyano) interactions.
To a solution of 5.8 mmole of {4-(4-Acetanilido-trans-1,3-butadienyl) -3-cyano-5,5-dimethyl-2(5H)-furanylidene}propanedinitrile (Compound 11b, Kay et al., 2004) in 30 ml of ethanol was added an equimolar quantity of pyrrolidine. The solution was refluxed 1 h, cooled and the product collected by filtration and washed with ethanol. λmax 530 nm (pyridine); 530 nm (DMF) log10ε 5.22. Final crystallization was from a 1:1 dichloromethane/ ethyl acetate mixture.
Diffraction data was extracted from the major of multiple intersecting lattices using RLATT (Bruker, 2004). The structure was solved by direct methods but refinement halted at R 0.20 for 3731 data with I>2σ(I). Inspection of data showed a large number with Fo>>Fc indicating coincidental contributions from the other contributing lattice(s). A total of 943 reflections which met the two criteria (1) I(obs)/I(calc) > 1.50 and (2) (I(obs)-I(calc)) > 2σ(I(obs)) were then excluded from the dataset. The conventional R for these rejected data was 0.47. The ratio criteria (1) was varied down to values of 1.05: although the agreement factors converged at around a ratio of 1.2 (R 0.078, for 2252 I>2σ(I) data) no signifcant changes occurred in final su values or parameters compared with the larger dataset. On the basis that another analysis of the data would be possible if the larger dataset was presented, the refinement was continued with the (ratio 1.5) 4280 independent remaining data within the limit of 29° theta. All methyl and tertiary H atoms were refined with Uiso 1.5 & 1.2 times respectively that of the Ueq of their parent atom.
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: RLATT (Bruker, 2004), SAINT (Bruker, 2005) and SADABS (Sheldrick, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).
![[Figure 1]](./lh2664fig1thm.gif)
| Fig. 1. Molecular structure of the asymmetic unit (Farrugia, 1997); displacement ellipsoids are shown at the 50% probability level. |
| C18H18N4O·CH2Cl2 | F000 = 816 |
| Mr = 391.29 | Dx = 1.345 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 5595 reflections |
| a = 6.8755 (8) Å | θ = 2.4–29.2º |
| b = 16.8913 (17) Å | µ = 0.35 mm−1 |
| c = 16.6677 (18) Å | T = 120 (2) K |
| β = 93.482 (8)º | Block, red |
| V = 1932.1 (4) Å3 | 0.30 × 0.15 × 0.13 mm |
| Z = 4 |
| Bruker–Nonius APEXII CCD area-detector diffractometer | 4280 independent reflections |
| Radiation source: fine-focus sealed tube | 2517 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.099 |
| Detector resolution: 8.192 pixels mm-1 | θmax = 29.0º |
| T = 120(2) K | θmin = 2.7º |
| φ and ω scans | h = −9→9 |
| Absorption correction: multi-scan (Blessing, 1995) | k = 0→23 |
| Tmin = 0.570, Tmax = 0.955 | l = 0→22 |
| 4280 measured reflections |
| Refinement on F2 | Secondary atom site location: difference Fourier map |
| Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
| R[F2 > 2σ(F2)] = 0.095 | H-atom parameters constrained |
| wR(F2) = 0.270 | w = 1/[σ2(Fo2) + (0.1824P)2] where P = (Fo2 + 2Fc2)/3 |
| S = 0.99 | (Δ/σ)max < 0.001 |
| 4280 reflections | Δρmax = 1.36 e Å−3 |
| 237 parameters | Δρmin = −0.47 e Å−3 |
| Primary atom site location: structure-invariant direct methods | Extinction correction: none |
| C18H18N4O·CH2Cl2 | V = 1932.1 (4) Å3 |
| Mr = 391.29 | Z = 4 |
| Monoclinic, P21/c | Mo Kα |
| a = 6.8755 (8) Å | µ = 0.35 mm−1 |
| b = 16.8913 (17) Å | T = 120 (2) K |
| c = 16.6677 (18) Å | 0.30 × 0.15 × 0.13 mm |
| β = 93.482 (8)º |
| Bruker–Nonius APEXII CCD area-detector diffractometer | 4280 independent reflections |
| Absorption correction: multi-scan (Blessing, 1995) | 2517 reflections with I > 2σ(I) |
| Tmin = 0.570, Tmax = 0.955 | Rint = 0.099 |
| 4280 measured reflections |
| R[F2 > 2σ(F2)] = 0.095 | 237 parameters |
| wR(F2) = 0.270 | H-atom parameters constrained |
| S = 0.99 | Δρmax = 1.36 e Å−3 |
| 4280 reflections | Δρmin = −0.47 e Å−3 |
Experimental. There were 36108 reflections measured in the data collection (43242 of which 7061 were rejected to 2theta 58 degrees & 73 were systematic absence violations) |
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. Four low theta angle reflections affected by the backstop were omitted. 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 | ||
| Cl1 | 0.2744 (2) | 0.45770 (7) | 0.31788 (7) | 0.0405 (4) | |
| Cl2 | 0.2711 (3) | 0.62862 (7) | 0.30173 (9) | 0.0578 (5) | |
| O1 | 0.7615 (4) | 0.90197 (14) | 0.42000 (15) | 0.0176 (6) | |
| N1 | 0.7450 (8) | 1.0058 (2) | 0.6850 (2) | 0.0461 (13) | |
| N2 | 0.7371 (6) | 1.1047 (2) | 0.4400 (2) | 0.0308 (9) | |
| N3 | 0.8028 (7) | 0.8020 (2) | 0.6872 (2) | 0.0382 (10) | |
| N4 | 0.7736 (5) | 0.41968 (17) | 0.40006 (18) | 0.0175 (7) | |
| C1 | 0.7496 (7) | 0.9959 (2) | 0.6163 (3) | 0.0250 (9) | |
| C2 | 0.7542 (6) | 0.9836 (2) | 0.5329 (2) | 0.0187 (8) | |
| C3 | 0.7462 (6) | 1.0505 (2) | 0.4810 (2) | 0.0218 (8) | |
| C4 | 0.7730 (5) | 0.7750 (2) | 0.4757 (2) | 0.0149 (7) | |
| C5 | 0.7705 (6) | 0.8175 (2) | 0.3964 (2) | 0.0160 (7) | |
| C6 | 0.7637 (5) | 0.9082 (2) | 0.5002 (2) | 0.0148 (7) | |
| C7 | 0.7736 (6) | 0.8325 (2) | 0.5364 (2) | 0.0156 (7) | |
| C8 | 0.9567 (6) | 0.8083 (2) | 0.3533 (2) | 0.0234 (8) | |
| H8A | 0.9604 | 0.8482 | 0.3107 | 0.035* | |
| H8B | 0.9611 | 0.7553 | 0.3295 | 0.035* | |
| H8C | 1.0691 | 0.8154 | 0.3916 | 0.035* | |
| C9 | 0.5876 (7) | 0.8032 (2) | 0.3437 (2) | 0.0248 (9) | |
| H9A | 0.4733 | 0.8102 | 0.3754 | 0.037* | |
| H9B | 0.5891 | 0.7492 | 0.3224 | 0.037* | |
| H9C | 0.5815 | 0.8410 | 0.2990 | 0.037* | |
| C10 | 0.7885 (6) | 0.8171 (2) | 0.6203 (2) | 0.0226 (8) | |
| C11 | 0.7752 (6) | 0.6928 (2) | 0.4885 (2) | 0.0186 (8) | |
| H11 | 0.7724 | 0.6756 | 0.5427 | 0.022* | |
| C12 | 0.7811 (6) | 0.6338 (2) | 0.4301 (2) | 0.0194 (8) | |
| H12 | 0.7896 | 0.6492 | 0.3756 | 0.023* | |
| C13 | 0.7752 (6) | 0.5539 (2) | 0.4481 (2) | 0.0189 (8) | |
| H13 | 0.7644 | 0.5377 | 0.5022 | 0.023* | |
| C14 | 0.7848 (6) | 0.4965 (2) | 0.3880 (2) | 0.0174 (7) | |
| H14 | 0.8006 | 0.5143 | 0.3347 | 0.021* | |
| C15 | 0.7243 (6) | 0.3835 (2) | 0.4769 (2) | 0.0187 (8) | |
| H15A | 0.5982 | 0.4037 | 0.4940 | 0.022* | |
| H15B | 0.8268 | 0.3944 | 0.5198 | 0.022* | |
| C16 | 0.7121 (6) | 0.2948 (2) | 0.4578 (2) | 0.0179 (8) | |
| H16A | 0.8381 | 0.2682 | 0.4716 | 0.021* | |
| H16B | 0.6091 | 0.2690 | 0.4874 | 0.021* | |
| C17 | 0.6631 (7) | 0.2927 (2) | 0.3685 (3) | 0.0273 (10) | |
| H17A | 0.5222 | 0.3017 | 0.3562 | 0.033* | |
| H17B | 0.7003 | 0.2413 | 0.3454 | 0.033* | |
| C18 | 0.7825 (7) | 0.3595 (2) | 0.3367 (2) | 0.0243 (9) | |
| H18A | 0.9184 | 0.3426 | 0.3298 | 0.029* | |
| H18B | 0.7245 | 0.3793 | 0.2847 | 0.029* | |
| C19 | 0.2652 (9) | 0.5381 (3) | 0.2501 (3) | 0.0406 (12) | |
| H19A | 0.3774 | 0.5352 | 0.2157 | 0.049* | |
| H19B | 0.1442 | 0.5349 | 0.2149 | 0.049* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Cl1 | 0.0591 (9) | 0.0256 (6) | 0.0371 (7) | 0.0013 (5) | 0.0050 (5) | 0.0016 (5) |
| Cl2 | 0.1031 (14) | 0.0237 (6) | 0.0465 (8) | −0.0009 (7) | 0.0047 (8) | 0.0022 (5) |
| O1 | 0.0335 (16) | 0.0064 (11) | 0.0131 (12) | 0.0004 (10) | 0.0044 (10) | 0.0004 (9) |
| N1 | 0.091 (4) | 0.024 (2) | 0.023 (2) | −0.006 (2) | 0.009 (2) | −0.0102 (16) |
| N2 | 0.047 (2) | 0.0151 (16) | 0.030 (2) | −0.0001 (16) | 0.0008 (16) | 0.0014 (15) |
| N3 | 0.063 (3) | 0.028 (2) | 0.023 (2) | −0.005 (2) | −0.0010 (18) | 0.0067 (16) |
| N4 | 0.0282 (18) | 0.0089 (14) | 0.0157 (15) | −0.0017 (12) | 0.0042 (12) | 0.0002 (11) |
| C1 | 0.041 (3) | 0.0099 (17) | 0.024 (2) | −0.0014 (16) | 0.0028 (18) | −0.0020 (14) |
| C2 | 0.028 (2) | 0.0070 (15) | 0.0210 (19) | −0.0003 (14) | 0.0015 (15) | −0.0024 (13) |
| C3 | 0.030 (2) | 0.0104 (17) | 0.025 (2) | −0.0013 (14) | 0.0018 (16) | −0.0033 (14) |
| C4 | 0.0151 (18) | 0.0083 (15) | 0.0213 (18) | −0.0007 (12) | 0.0004 (13) | −0.0016 (13) |
| C5 | 0.024 (2) | 0.0063 (15) | 0.0175 (17) | −0.0030 (13) | 0.0010 (14) | −0.0038 (12) |
| C6 | 0.0200 (18) | 0.0115 (16) | 0.0129 (16) | 0.0021 (13) | −0.0007 (12) | −0.0012 (12) |
| C7 | 0.0216 (19) | 0.0112 (15) | 0.0141 (16) | −0.0020 (13) | 0.0009 (13) | 0.0010 (13) |
| C8 | 0.033 (2) | 0.0152 (17) | 0.0230 (19) | −0.0004 (16) | 0.0060 (16) | 0.0006 (15) |
| C9 | 0.042 (3) | 0.0128 (17) | 0.0189 (19) | −0.0034 (16) | −0.0066 (16) | −0.0003 (14) |
| C10 | 0.031 (2) | 0.0120 (17) | 0.024 (2) | −0.0043 (15) | −0.0023 (16) | −0.0018 (14) |
| C11 | 0.023 (2) | 0.0105 (16) | 0.0226 (18) | −0.0010 (14) | 0.0026 (14) | 0.0036 (14) |
| C12 | 0.024 (2) | 0.0100 (16) | 0.0238 (19) | −0.0005 (14) | 0.0004 (15) | −0.0002 (14) |
| C13 | 0.028 (2) | 0.0072 (15) | 0.0219 (19) | −0.0015 (13) | 0.0034 (15) | −0.0007 (13) |
| C14 | 0.0207 (19) | 0.0081 (16) | 0.0233 (19) | 0.0021 (13) | 0.0020 (14) | 0.0019 (13) |
| C15 | 0.026 (2) | 0.0129 (17) | 0.0173 (18) | −0.0016 (14) | 0.0023 (14) | 0.0008 (13) |
| C16 | 0.0220 (19) | 0.0093 (16) | 0.0221 (18) | 0.0018 (13) | −0.0011 (14) | 0.0022 (13) |
| C17 | 0.040 (3) | 0.0142 (18) | 0.027 (2) | −0.0056 (17) | −0.0036 (18) | −0.0025 (15) |
| C18 | 0.045 (3) | 0.0084 (16) | 0.0198 (19) | 0.0029 (16) | 0.0033 (16) | −0.0041 (14) |
| C19 | 0.064 (4) | 0.036 (3) | 0.022 (2) | −0.001 (2) | 0.003 (2) | 0.0043 (18) |
| Cl1—C19 | 1.766 (5) | C9—H9A | 0.9800 |
| Cl2—C19 | 1.753 (5) | C9—H9B | 0.9800 |
| O1—C6 | 1.341 (4) | C9—H9C | 0.9800 |
| O1—C5 | 1.482 (4) | C11—C12 | 1.397 (5) |
| N1—C1 | 1.160 (6) | C11—H11 | 0.9500 |
| N2—C3 | 1.141 (5) | C12—C13 | 1.384 (5) |
| N3—C10 | 1.142 (5) | C12—H12 | 0.9500 |
| N4—C14 | 1.317 (4) | C13—C14 | 1.397 (5) |
| N4—C18 | 1.471 (5) | C13—H13 | 0.9500 |
| N4—C15 | 1.477 (5) | C14—H14 | 0.9500 |
| C1—C2 | 1.408 (5) | C15—C16 | 1.533 (5) |
| C2—C6 | 1.388 (5) | C15—H15A | 0.9900 |
| C2—C3 | 1.423 (5) | C15—H15B | 0.9900 |
| C4—C7 | 1.402 (5) | C16—C17 | 1.505 (5) |
| C4—C11 | 1.405 (5) | C16—H16A | 0.9900 |
| C4—C5 | 1.503 (5) | C16—H16B | 0.9900 |
| C5—C9 | 1.510 (5) | C17—C18 | 1.510 (6) |
| C5—C8 | 1.514 (6) | C17—H17A | 0.9900 |
| C6—C7 | 1.412 (5) | C17—H17B | 0.9900 |
| C7—C10 | 1.421 (5) | C18—H18A | 0.9900 |
| C8—H8A | 0.9800 | C18—H18B | 0.9900 |
| C8—H8B | 0.9800 | C19—H19A | 0.9900 |
| C8—H8C | 0.9800 | C19—H19B | 0.9900 |
| C6—O1—C5 | 110.0 (3) | C13—C12—C11 | 122.9 (4) |
| C14—N4—C18 | 124.5 (3) | C13—C12—H12 | 118.6 |
| C14—N4—C15 | 124.0 (3) | C11—C12—H12 | 118.6 |
| C18—N4—C15 | 111.0 (3) | C12—C13—C14 | 121.2 (4) |
| N1—C1—C2 | 179.6 (5) | C12—C13—H13 | 119.4 |
| C6—C2—C1 | 121.8 (3) | C14—C13—H13 | 119.4 |
| C6—C2—C3 | 119.5 (3) | N4—C14—C13 | 124.7 (4) |
| C1—C2—C3 | 118.7 (3) | N4—C14—H14 | 117.7 |
| N2—C3—C2 | 178.8 (5) | C13—C14—H14 | 117.7 |
| C7—C4—C11 | 125.2 (3) | N4—C15—C16 | 103.7 (3) |
| C7—C4—C5 | 107.6 (3) | N4—C15—H15A | 111.0 |
| C11—C4—C5 | 127.2 (3) | C16—C15—H15A | 111.0 |
| O1—C5—C4 | 103.0 (3) | N4—C15—H15B | 111.0 |
| O1—C5—C9 | 105.2 (3) | C16—C15—H15B | 111.0 |
| C4—C5—C9 | 113.6 (3) | H15A—C15—H15B | 109.0 |
| O1—C5—C8 | 106.0 (3) | C17—C16—C15 | 103.6 (3) |
| C4—C5—C8 | 113.8 (3) | C17—C16—H16A | 111.0 |
| C9—C5—C8 | 113.9 (3) | C15—C16—H16A | 111.0 |
| O1—C6—C2 | 117.7 (3) | C17—C16—H16B | 111.0 |
| O1—C6—C7 | 110.6 (3) | C15—C16—H16B | 111.0 |
| C2—C6—C7 | 131.7 (3) | H16A—C16—H16B | 109.0 |
| C4—C7—C6 | 108.7 (3) | C16—C17—C18 | 103.7 (3) |
| C4—C7—C10 | 125.4 (3) | C16—C17—H17A | 111.0 |
| C6—C7—C10 | 125.8 (3) | C18—C17—H17A | 111.0 |
| C5—C8—H8A | 109.5 | C16—C17—H17B | 111.0 |
| C5—C8—H8B | 109.5 | C18—C17—H17B | 111.0 |
| H8A—C8—H8B | 109.5 | H17A—C17—H17B | 109.0 |
| C5—C8—H8C | 109.5 | N4—C18—C17 | 102.5 (3) |
| H8A—C8—H8C | 109.5 | N4—C18—H18A | 111.3 |
| H8B—C8—H8C | 109.5 | C17—C18—H18A | 111.3 |
| C5—C9—H9A | 109.5 | N4—C18—H18B | 111.3 |
| C5—C9—H9B | 109.5 | C17—C18—H18B | 111.3 |
| H9A—C9—H9B | 109.5 | H18A—C18—H18B | 109.2 |
| C5—C9—H9C | 109.5 | Cl2—C19—Cl1 | 111.0 (3) |
| H9A—C9—H9C | 109.5 | Cl2—C19—H19A | 109.4 |
| H9B—C9—H9C | 109.5 | Cl1—C19—H19A | 109.4 |
| N3—C10—C7 | 177.6 (4) | Cl2—C19—H19B | 109.4 |
| C12—C11—C4 | 126.9 (4) | Cl1—C19—H19B | 109.4 |
| C12—C11—H11 | 116.6 | H19A—C19—H19B | 108.0 |
| C4—C11—H11 | 116.6 | ||
| C6—O1—C5—C4 | 1.4 (4) | O1—C6—C7—C4 | −1.5 (4) |
| C6—O1—C5—C9 | 120.7 (3) | C2—C6—C7—C4 | 177.8 (4) |
| C6—O1—C5—C8 | −118.4 (3) | O1—C6—C7—C10 | 176.5 (4) |
| C7—C4—C5—O1 | −2.3 (4) | C2—C6—C7—C10 | −4.2 (7) |
| C11—C4—C5—O1 | 178.0 (4) | C7—C4—C11—C12 | −177.7 (4) |
| C7—C4—C5—C9 | −115.5 (3) | C5—C4—C11—C12 | 2.0 (6) |
| C11—C4—C5—C9 | 64.8 (5) | C4—C11—C12—C13 | −177.4 (4) |
| C7—C4—C5—C8 | 112.0 (3) | C11—C12—C13—C14 | −178.9 (4) |
| C11—C4—C5—C8 | −67.8 (5) | C18—N4—C14—C13 | 179.6 (4) |
| C5—O1—C6—C2 | −179.4 (3) | C15—N4—C14—C13 | 8.1 (6) |
| C5—O1—C6—C7 | 0.0 (4) | C12—C13—C14—N4 | −177.6 (4) |
| C1—C2—C6—O1 | 178.0 (4) | C14—N4—C15—C16 | 175.1 (4) |
| C3—C2—C6—O1 | −1.1 (6) | C18—N4—C15—C16 | 2.5 (4) |
| C1—C2—C6—C7 | −1.2 (7) | N4—C15—C16—C17 | −25.4 (4) |
| C3—C2—C6—C7 | 179.7 (4) | C15—C16—C17—C18 | 38.8 (4) |
| C11—C4—C7—C6 | −177.9 (4) | C14—N4—C18—C17 | −151.3 (4) |
| C5—C4—C7—C6 | 2.3 (4) | C15—N4—C18—C17 | 21.1 (4) |
| C11—C4—C7—C10 | 4.1 (6) | C16—C17—C18—N4 | −36.7 (4) |
| C5—C4—C7—C10 | −175.7 (4) |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C14—H14···N1i | 0.95 | 2.52 | 3.378 (5) | 150 |
| C18—H18B···N1i | 0.99 | 2.56 | 3.400 (5) | 142 |
| Symmetry codes: (i) x, −y+3/2, z−1/2. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C14—H14···N1i | 0.95 | 2.52 | 3.378 (5) | 150 |
| C18—H18B···N1i | 0.99 | 2.56 | 3.400 (5) | 142 |
| Symmetry codes: (i) x, −y+3/2, z−1/2. |
We thank Dr J. Wikaira of the University of Canterbury for her assistance in the data collection.
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We have previously reported on the synthesis of a number of high figure of merit chromophores for nonlinear optics (Kay et al., 2004), and the X-ray crystallographic and structural properties of crucial dye precursors used (Gainsford et al., 2007, 2008a,b). A closely related compound 2-[3-Cyano-5,5-dimethyl-4-(6-pyrrolidin-1-yl-hexa -1,3,5-trienyl)-5H-furan-2-ylidene]-malononitrile will be reported shortly (Gainsford et al., 2008c).
In the crystal structure, the molecules (Fig. 1) are bound into planar dimer units via a polyene C–H and pyrollidine C–H bifurcated interaction with one cyano nitrogen atom (N1, Table 1). Other very weak intermolecular interactions providing inter-plane or solvent links, such as the one between the dichloromethane H19A and N1 (2.70 Å), are consistent with the difficulty found in obtaining a good single-crystal of this compound.