3,5-Bis{3-[4-(dimethyl­amino)phen­yl]­prop-2-enyl­idene}-1-methyl-4-piperidone and 3,5-bis[3-(4-meth­oxy­phen­yl)prop-2-enyl­idene]-1-methyl-4-piperidone: potential biophotonic materials

The structures of the title compounds, C₂₈H₃₃N₃O, (I), and C₂₆H₂₇NO₃, (II), together with their two-photon absorption properties and fluorescence activities are reported. Mol­ecules of (II) reside on crystallographic mirror planes containing the piperidone C=O group and N-methyl H atoms. Because of the conjugation between the donor and acceptor parts, the central heterocycle in both (I) and (II) exhibits a flattened boat conformation, with deviations of the N atom and the opposite C atom from the planar fragment. The dihedral angles between the coplanar heterocyclic atoms and terminal C₆ rings are less than 20° in both (I) and (II). In (I), the N-methyl group of the ring occupies an equatorial position, but in (II) it is positioned in an axial site. In the crystal structure of (I), weak inter­molecular C—H...π(arene) and C—H...O steric contacts link the mol­ecules along the a axis. In the crystal structure of (II), mol­ecules form stacks along the b axis.

S1. Comment

There is on-going interest in organic compounds that exhibit two-photon absorption (TPA) and two-photon excited fluorescence (TPEF). Such compounds can produce visible light when excited with IR radiation and allow penetration deep into biological tissue without absorption or causing damage. Such compounds find application as fluorescent molecular probes/markers and visualization agents in high-resolution two-photon microscopy in biomedical research and diagnostics (So et al., 2003).

Continuing our investigations of these organic compounds (Nesterov, 2004; Nesterov & Nesterov, 2004; Nesterov et al., 2003, 2007a,b; Sarkisov et al., 2005), two compounds, (I) and (II), with the general structure D–π–A–π–D were synthesized and their structures, TPA properties and fluorescence activities have been characterized (D = donor and A = acceptor). Comparison of the two structures with 3,5-diarylidene-4-piperidone systems has shown that (I) and (II) are similar to piperidones used as anticancer agents (Jia et al., 1988; Dimmock et al., 2001). Combination of two such properties opens the possibility of their application as agents for localization of the cancer cells with two-photon exited fluorescence and as potential agents for photodynamic treatment of cancer (PDT).

Compounds (I) and (II) (Figs. 1 and 2) contain two dimethylaminophenyl or methoxyphenyl donor groups connected with the central acceptor 1-methyl-4-piperidone ring via a conjugated bridge. In both molecules the central heterocycle adopts a flattened boat conformation; atoms N1 and C4 lie 0.714 (1) and 0.055 (1) Å, respectively, out of the C2/C3/C5/C6 plane in (I) and 0.659 (1) and 0.039 (1) Å from the C2/C3/C3A/C2A plane in (II) [the suffix A denotes the symmetry-related positions; the maximum deviations of one of the four atoms that make up the plane from that plane are 0.023 (1) Å for (I) and 0.0 Å for (II)].

Both molecules can be formally divided into three almost planar fragments, viz. the planar part of the heterocycle (A), and the planar fragments that consist of a Ph ring and the bridging atoms (B and C) (see scheme). In (I), the dihedral angles between A/B and A/C are 5.8 (1) and 10.2 (1)°, respectively, with similar angles in (II) of 20.0 (1)° (A/B). In (I), the Me₂N– groups form different dihedral angles with the phenyl rings [that between N2/C16/C17 and C10–C15 is 6.0 (1)°, and that between N3/C27/C28 and C21–C26 is 16.7 (1)°]. In (II), the MeO– group lies in the plane of the aromatic ring [C10—C11—O2—C14 = 178.8 (3)°] and its geometric parameters are in good agreement with literature data (Gallagher et al., 2001). The nonplanarity of both compounds is caused by short intramolecular contacts [H2B···H8A = 2.16 Å, H8A···H15A = 2.21 Å, H6A···H19A = 2.21 Å and H19A···H26A = 2.32 Å in (I), and H2A···H6A = 2.28 Å and H6A···H13A = 2.34 Å in (II)] that are comparable to the sum of the van der Waals radii of the H atoms (Rowland & Taylor, 1996).

In both structures, atom N1 (in the piperidone ring) has pyramidal coordination, the sum of bond angles being 331.0 (2)° in (I) and 334.3 (2)° in (II). In (I), the methyl group on atom N1 occupies an equatorial position, while in (II) it is positioned axially. Such an unfavorable orientation of atom C1 in (II) is a reason for the presence of an intramolecular steric contact [C1···C4 = 3.282 (3) Å] equal to the sum of the van der Waals radii of both atoms (Rowland & Taylor, 1996). The bond-length distributions in the π-conjugated bridges definitely show an alternation of single and double C—C bond lengths [especially in (I) with strong N(CH₃)₂ donor groups]. with values close to the standard conjugated values (Allen et al., 1987).

In (I), intermolecular C11—H11A···π(arene) interactions [H11A···C24ⁱ = 2.85 Å and H11A···C25ⁱ = 2.87 Å; symmetry code [please check]: (i) x - 1/2, -y + 1/2, 1/2 + z + 1/2; Fig. 3] and weak intermolecular steric contacts [C27—H27A···O1ⁱⁱ; H27A···O1ⁱⁱ= 2.57 Å; symmetry code: (ii) - x + 1, -y, -z + 1] link molecules along the a axis. In (II), molecules form stacks along the b axis. Such packing is a reason for the existence of intermolecular steric contacts [N1···C4ⁱⁱⁱ = 2.967 (3) Å; symmetry code: (iii) please provide] that are shorter than the sum of the van der Waals radii of the two atoms (Rowland & Taylor, 1996).

The strong TPEF observed in (I), as opposed to a lack of TPEF in (II), is associated with the electron donor properties of the pendant group. Thus, the –N(CH₃)₂ group in (I) is a much stronger electron donor than the –OCH₃ group in (II). In general, strong TPEF can be expected in compounds with strong electron acceptor properties of the core, strong electron donor properties of the pendant groups, and long π-conjugated electron bridges between the core and the pendant groups. A detailed discussion of the connection between the molecular structure and TPEF was presented by Sarkisov et al. (2005). These results indicate that (I) can potentially be used as a two-photon fluorescent marker/molecular probe in two-photon fluorescent microscopy for biomedical research.

Related literature

For related literature, see: Allen et al. (1987); Dimmock et al. (2001); Gallagher et al. (2001); Jia et al. (1988); Nesterov et al. (2003, 2007a, 2007b); Nesterov, 2004; Nesterov & Nesterov, 2004; Rowland & Taylor (1996); Sarkisov et al. (2005)

S2. Experimental

The title compounds were synthesized from literature procedures (Jia et al., 1988; Nesterov et al., 2003). The precipitates were isolated and recrystallized from tetrahydrofuran [m.p. 471 K, yield 83% for (I), and m.p. 454 K, yield 87% for (II)]. Crystals were obtained by isothermic evaporation of ethanol solutions of (I) and (II).

Compounds (I) and (II) were investigated in terms of their possible fluorescence and use as TPA materials. Compound (I) demonstrated single-photon excited fluorescence (SPEF) of a red color while pumped with a UV lamp and pulsed green (532 nm) and UV (337 nm) lasers. In the case of 532 nm pumping, the SPEF was approximately 60% of that produced by reference dye Rhodamine 6 G (Sarkisov et al., 2005). Compound (I) also produced relatively strong red TPEF, while being pumped with pulsed IR radiation at 876 nm. The TPA coefficient and molecular cross section for (I) are 7.0 cm GW^-1 and 2650 cm⁴ s photon^-1 molecule^-1, and is twice that of [is this refering to one or both of the preceding values?] the benchmark reference dye Rhodamine B (Sarkisov et al., 2005). The intensity of TPEF was 37% of that produced by Rhodamine B. Compound (II) produced a weak orange SPEF (0.2% of that produced by Rhodamine 6 G) while pumped only with a UV lamp or pulsed UV laser. There was no SPEF in the case of green pumping. This can be partially explained by the fact that the energy of green photons (2.2 eV) is way below the optical absorption band of the compound (between 2.7 and 3.4 eV). No TPEF was produced during pumping with a pulsed IR laser at 876 nm, despite the fact that the double energy of the IR photon (2.85 eV) is well inside the absorption band.

S3. Refinement

The absolute structure for (II) was not determined reliably; thus, for (II), Friedel pairs were merged before refinement. In (II), the two H atoms of the N-methyl group were located from difference Fourier maps and were refined with isotropic parameters [the molecule occupies a special position in the crystal (the plane passes through atoms O1, N1, C4 and H1B); C1—H1A = 0.99 (3) Å and C1—H1B = 0.98 (5) Å]. All H atoms in (I) and the remaining H atoms in (II) were placed in calculated positions (C—H = 0.95–0.99 Å) and refined in a rigid-group model [U_iso(H) = 1.2U_eq(C) and 1.5U_eq(C) for aromatic and methyl (AFIX 137) H atoms, respectively].

Computing details

For both compounds, data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXTL (Bruker, 2005); program(s) used to refine structure: SHELXTL (Bruker, 2005); molecular graphics: SHELXTL (Bruker, 2005); software used to prepare material for publication: SHELXTL (Bruker, 2005).

Figures

	Fig. 1. : A view of (I), with the atom-numbering scheme. The non-H atoms are shown with displacement ellipsoids drawn at the 50% probability level. H atoms are drawn as circles of arbitrary small radius for clarity.
	Fig. 2. : A view of (II), with the atom-numbering scheme. The non-H atoms are shown with displacement ellipsoids drawn at the 50% probability level. H atoms are drawn as circles of arbitrary small radius for clarity.
	Fig. 3. : A projection of the crystal packing of (I) along the b axis. Dashed lines represent the intermolecular C—H···π(arene, C21–C26) and C—H···O contacts. H atoms not involved in these interactions have been omitted for clarity. [Symmetry codes: (C) -x + 1, -y, -z + 1; (E) -x + 1/2, y + 1/2, -z + 1/2; (G) -x + 3/2, y + 1/2, -z + 1/2; (H) x - 1/2, -y + 1/2, z + 1/2; (J) x + 1/2, -y + 1/2, z - 1/2]

(I) 3,5-Bis{3-[4-(dimethylamino)phenyl]prop-2-enylidene}-1-methyl-4-piperidone

Crystal data

C28H33N3O	F(000) = 920
Mr = 427.57	Dx = 1.210 Mg m^−3
Monoclinic, P21/n	Melting point: 471 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 15.5459 (16) Å	Cell parameters from 2979 reflections
b = 6.1017 (6) Å	θ = 3–23°
c = 25.163 (3) Å	µ = 0.07 mm^−1
β = 100.539 (2)°	T = 173 K
V = 2346.6 (4) Å^3	Plate, red
Z = 4	0.34 × 0.14 × 0.06 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer	4641 independent reflections
Radiation source: fine-focus sealed tube	3393 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
ϕ and ω scans	θmax = 26.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1995)	h = −19→19
Tmin = 0.905, Tmax = 0.996	k = −7→7
23500 measured reflections	l = −31→31

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.122	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0504P)^2 + 0.77P] where P = (Fo^2 + 2Fc^2)/3
4641 reflections	(Δ/σ)max = 0.001
294 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.17 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.47448 (8)	0.10738 (19)	0.71223 (5)	0.0383 (3)
N1	0.63284 (9)	0.6230 (2)	0.75048 (5)	0.0314 (3)
N2	0.34341 (12)	0.7444 (3)	1.08654 (7)	0.0596 (5)
N3	0.67719 (11)	0.4831 (2)	0.33889 (6)	0.0401 (4)
C1	0.68723 (12)	0.8177 (3)	0.76319 (8)	0.0407 (5)
H1A	0.7120	0.8195	0.8019	0.061*
H1B	0.6515	0.9492	0.7538	0.061*
H1C	0.7347	0.8153	0.7424	0.061*
C2	0.55952 (11)	0.6251 (3)	0.77920 (7)	0.0313 (4)
H2A	0.5208	0.7507	0.7666	0.038*
H2B	0.5817	0.6440	0.8184	0.038*
C3	0.50783 (10)	0.4149 (3)	0.76986 (6)	0.0282 (4)
C4	0.51027 (11)	0.2885 (3)	0.71974 (7)	0.0291 (4)
C5	0.55556 (11)	0.3896 (3)	0.67918 (6)	0.0295 (4)
C6	0.59930 (12)	0.6078 (3)	0.69252 (7)	0.0356 (4)
H6A	0.6480	0.6249	0.6725	0.043*
H6B	0.5567	0.7272	0.6813	0.043*
C7	0.45826 (11)	0.3426 (3)	0.80506 (6)	0.0320 (4)
H7A	0.4283	0.2076	0.7969	0.038*
C8	0.44699 (11)	0.4524 (3)	0.85370 (6)	0.0331 (4)
H8A	0.4758	0.5889	0.8618	0.040*
C9	0.39848 (11)	0.3752 (3)	0.88863 (7)	0.0340 (4)
H9A	0.3701	0.2388	0.8796	0.041*
C10	0.38433 (11)	0.4761 (3)	0.93852 (7)	0.0323 (4)
C11	0.33181 (11)	0.3736 (3)	0.97027 (7)	0.0366 (4)
H11A	0.3055	0.2372	0.9586	0.044*
C12	0.31641 (12)	0.4623 (3)	1.01810 (7)	0.0409 (5)
H12A	0.2789	0.3880	1.0380	0.049*
C13	0.35509 (12)	0.6590 (3)	1.03753 (7)	0.0393 (5)
C14	0.40751 (13)	0.7663 (3)	1.00571 (8)	0.0437 (5)
H14A	0.4338	0.9027	1.0174	0.052*
C15	0.42130 (12)	0.6768 (3)	0.95786 (7)	0.0400 (5)
H15A	0.4571	0.7534	0.9372	0.048*
C16	0.28310 (15)	0.6442 (4)	1.11632 (8)	0.0652 (7)
H16A	0.2946	0.4864	1.1195	0.098*
H16B	0.2230	0.6687	1.0973	0.098*
H16C	0.2906	0.7092	1.1525	0.098*
C17	0.3813 (2)	0.9533 (4)	1.10508 (9)	0.0765 (8)
H17A	0.4441	0.9514	1.1045	0.115*
H17B	0.3722	0.9802	1.1420	0.115*
H17C	0.3532	1.0699	1.0813	0.115*
C18	0.55512 (11)	0.2867 (3)	0.63163 (7)	0.0316 (4)
H18A	0.5303	0.1440	0.6281	0.038*
C19	0.58822 (11)	0.3697 (3)	0.58584 (7)	0.0338 (4)
H19A	0.6128	0.5127	0.5879	0.041*
C20	0.58586 (11)	0.2540 (3)	0.54022 (7)	0.0337 (4)
H20A	0.5652	0.1077	0.5412	0.040*
C21	0.61039 (11)	0.3205 (3)	0.48959 (7)	0.0309 (4)
C22	0.59848 (11)	0.1750 (3)	0.44612 (7)	0.0323 (4)
H22A	0.5750	0.0341	0.4509	0.039*
C23	0.61921 (11)	0.2259 (3)	0.39665 (7)	0.0317 (4)
H23A	0.6088	0.1217	0.3681	0.038*
C24	0.65555 (11)	0.4306 (3)	0.38801 (7)	0.0310 (4)
C25	0.66843 (12)	0.5794 (3)	0.43171 (7)	0.0342 (4)
H25A	0.6929	0.7194	0.4273	0.041*
C26	0.64614 (11)	0.5257 (3)	0.48061 (7)	0.0340 (4)
H26A	0.6552	0.6302	0.5091	0.041*
C27	0.67946 (13)	0.3158 (3)	0.29825 (7)	0.0383 (4)
H27A	0.6254	0.2296	0.2935	0.057*
H27B	0.7298	0.2193	0.3099	0.057*
H27C	0.6847	0.3855	0.2639	0.057*
C28	0.72492 (15)	0.6832 (3)	0.33276 (8)	0.0511 (6)
H28A	0.6933	0.8087	0.3441	0.077*
H28B	0.7304	0.7009	0.2948	0.077*
H28C	0.7833	0.6750	0.3553	0.077*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0542 (8)	0.0292 (7)	0.0333 (7)	−0.0080 (6)	0.0132 (6)	−0.0043 (5)
N1	0.0335 (8)	0.0329 (8)	0.0296 (8)	−0.0046 (6)	0.0110 (6)	−0.0077 (6)
N2	0.0671 (12)	0.0772 (14)	0.0406 (10)	0.0047 (11)	0.0263 (9)	−0.0147 (10)
N3	0.0636 (11)	0.0309 (8)	0.0308 (8)	−0.0020 (8)	0.0219 (8)	0.0006 (7)
C1	0.0399 (10)	0.0411 (11)	0.0433 (11)	−0.0104 (9)	0.0134 (9)	−0.0121 (9)
C2	0.0342 (9)	0.0339 (10)	0.0276 (9)	−0.0017 (8)	0.0106 (7)	−0.0063 (7)
C3	0.0304 (9)	0.0281 (9)	0.0258 (9)	0.0016 (7)	0.0048 (7)	−0.0012 (7)
C4	0.0338 (9)	0.0266 (9)	0.0273 (9)	0.0016 (7)	0.0061 (7)	−0.0005 (7)
C5	0.0334 (9)	0.0301 (9)	0.0255 (9)	0.0019 (7)	0.0066 (7)	−0.0007 (7)
C6	0.0449 (11)	0.0348 (10)	0.0299 (9)	−0.0045 (8)	0.0138 (8)	−0.0021 (8)
C7	0.0356 (10)	0.0330 (10)	0.0276 (9)	−0.0020 (8)	0.0060 (7)	−0.0012 (7)
C8	0.0374 (10)	0.0366 (10)	0.0267 (9)	−0.0022 (8)	0.0094 (8)	−0.0023 (8)
C9	0.0356 (10)	0.0373 (10)	0.0291 (9)	−0.0047 (8)	0.0062 (7)	−0.0033 (8)
C10	0.0306 (9)	0.0404 (10)	0.0273 (9)	−0.0001 (8)	0.0086 (7)	−0.0009 (8)
C11	0.0339 (10)	0.0448 (11)	0.0319 (10)	−0.0059 (8)	0.0078 (8)	0.0015 (8)
C12	0.0357 (10)	0.0576 (13)	0.0321 (10)	0.0001 (9)	0.0130 (8)	0.0071 (9)
C13	0.0379 (10)	0.0525 (12)	0.0288 (10)	0.0085 (9)	0.0095 (8)	−0.0036 (9)
C14	0.0514 (12)	0.0434 (11)	0.0390 (11)	−0.0040 (10)	0.0154 (9)	−0.0097 (9)
C15	0.0454 (11)	0.0442 (11)	0.0336 (10)	−0.0078 (9)	0.0156 (9)	−0.0036 (9)
C16	0.0681 (15)	0.098 (2)	0.0346 (11)	0.0301 (14)	0.0241 (11)	0.0078 (12)
C17	0.135 (2)	0.0547 (15)	0.0432 (13)	0.0216 (16)	0.0260 (15)	−0.0123 (12)
C18	0.0362 (10)	0.0311 (10)	0.0283 (9)	−0.0007 (8)	0.0080 (7)	−0.0016 (7)
C19	0.0404 (10)	0.0355 (10)	0.0266 (9)	−0.0032 (8)	0.0091 (8)	−0.0027 (8)
C20	0.0372 (10)	0.0350 (10)	0.0299 (9)	−0.0044 (8)	0.0090 (8)	−0.0041 (8)
C21	0.0339 (9)	0.0335 (10)	0.0260 (9)	0.0006 (8)	0.0076 (7)	−0.0026 (7)
C22	0.0377 (10)	0.0304 (10)	0.0299 (9)	−0.0063 (8)	0.0094 (8)	−0.0032 (7)
C23	0.0393 (10)	0.0306 (9)	0.0264 (9)	−0.0006 (8)	0.0091 (7)	−0.0059 (7)
C24	0.0363 (9)	0.0299 (9)	0.0280 (9)	0.0043 (8)	0.0094 (7)	0.0007 (7)
C25	0.0439 (10)	0.0262 (9)	0.0342 (10)	−0.0002 (8)	0.0116 (8)	−0.0015 (8)
C26	0.0419 (10)	0.0311 (10)	0.0300 (9)	−0.0003 (8)	0.0094 (8)	−0.0078 (8)
C27	0.0481 (11)	0.0409 (11)	0.0277 (9)	0.0042 (9)	0.0117 (8)	−0.0008 (8)
C28	0.0776 (15)	0.0396 (12)	0.0417 (12)	−0.0087 (11)	0.0254 (11)	0.0019 (9)

Geometric parameters (Å, º)

O1—C4	1.236 (2)	C12—H12A	0.9500
N1—C2	1.457 (2)	C13—C14	1.404 (3)
N1—C6	1.459 (2)	C14—C15	1.374 (2)
N1—C1	1.460 (2)	C14—H14A	0.9500
N2—C13	1.381 (2)	C15—H15A	0.9500
N2—C16	1.439 (3)	C16—H16A	0.9800
N2—C17	1.445 (3)	C16—H16B	0.9800
N3—C24	1.377 (2)	C16—H16C	0.9800
N3—C27	1.450 (2)	C17—H17A	0.9800
N3—C28	1.451 (2)	C17—H17B	0.9800
C1—H1A	0.9800	C17—H17C	0.9800
C1—H1B	0.9800	C18—C19	1.437 (2)
C1—H1C	0.9800	C18—H18A	0.9500
C2—C3	1.509 (2)	C19—C20	1.343 (2)
C2—H2A	0.9900	C19—H19A	0.9500
C2—H2B	0.9900	C20—C21	1.453 (2)
C3—C7	1.350 (2)	C20—H20A	0.9500
C3—C4	1.484 (2)	C21—C22	1.395 (2)
C4—C5	1.477 (2)	C21—C26	1.404 (2)
C5—C18	1.350 (2)	C22—C23	1.377 (2)
C5—C6	1.505 (2)	C22—H22A	0.9500
C6—H6A	0.9900	C23—C24	1.404 (2)
C6—H6B	0.9900	C23—H23A	0.9500
C7—C8	1.434 (2)	C24—C25	1.412 (2)
C7—H7A	0.9500	C25—C26	1.378 (2)
C8—C9	1.344 (2)	C25—H25A	0.9500
C8—H8A	0.9500	C26—H26A	0.9500
C9—C10	1.451 (2)	C27—H27A	0.9800
C9—H9A	0.9500	C27—H27B	0.9800
C10—C11	1.391 (2)	C27—H27C	0.9800
C10—C15	1.402 (3)	C28—H28A	0.9800
C11—C12	1.380 (2)	C28—H28B	0.9800
C11—H11A	0.9500	C28—H28C	0.9800
C12—C13	1.391 (3)
C2—N1—C6	109.10 (13)	C15—C14—C13	120.93 (19)
C2—N1—C1	111.01 (13)	C15—C14—H14A	119.5
C6—N1—C1	110.94 (14)	C13—C14—H14A	119.5
C13—N2—C16	120.6 (2)	C14—C15—C10	122.12 (18)
C13—N2—C17	120.59 (19)	C14—C15—H15A	118.9
C16—N2—C17	118.19 (18)	C10—C15—H15A	118.9
C24—N3—C27	120.70 (15)	N2—C16—H16A	109.5
C24—N3—C28	120.32 (15)	N2—C16—H16B	109.5
C27—N3—C28	116.01 (14)	H16A—C16—H16B	109.5
N1—C1—H1A	109.5	N2—C16—H16C	109.5
N1—C1—H1B	109.5	H16A—C16—H16C	109.5
H1A—C1—H1B	109.5	H16B—C16—H16C	109.5
N1—C1—H1C	109.5	N2—C17—H17A	109.5
H1A—C1—H1C	109.5	N2—C17—H17B	109.5
H1B—C1—H1C	109.5	H17A—C17—H17B	109.5
N1—C2—C3	110.97 (13)	N2—C17—H17C	109.5
N1—C2—H2A	109.4	H17A—C17—H17C	109.5
C3—C2—H2A	109.4	H17B—C17—H17C	109.5
N1—C2—H2B	109.4	C5—C18—C19	127.00 (17)
C3—C2—H2B	109.4	C5—C18—H18A	116.5
H2A—C2—H2B	108.0	C19—C18—H18A	116.5
C7—C3—C4	119.61 (15)	C20—C19—C18	122.82 (17)
C7—C3—C2	121.81 (15)	C20—C19—H19A	118.6
C4—C3—C2	118.56 (14)	C18—C19—H19A	118.6
O1—C4—C5	121.73 (15)	C19—C20—C21	129.20 (17)
O1—C4—C3	120.89 (15)	C19—C20—H20A	115.4
C5—C4—C3	117.37 (15)	C21—C20—H20A	115.4
C18—C5—C4	119.50 (16)	C22—C21—C26	116.18 (15)
C18—C5—C6	122.55 (15)	C22—C21—C20	119.41 (16)
C4—C5—C6	117.94 (14)	C26—C21—C20	124.42 (15)
N1—C6—C5	110.08 (14)	C23—C22—C21	123.07 (16)
N1—C6—H6A	109.6	C23—C22—H22A	118.5
C5—C6—H6A	109.6	C21—C22—H22A	118.5
N1—C6—H6B	109.6	C22—C23—C24	120.53 (16)
C5—C6—H6B	109.6	C22—C23—H23A	119.7
H6A—C6—H6B	108.2	C24—C23—H23A	119.7
C3—C7—C8	125.53 (16)	N3—C24—C23	121.17 (15)
C3—C7—H7A	117.2	N3—C24—C25	121.75 (16)
C8—C7—H7A	117.2	C23—C24—C25	117.09 (15)
C9—C8—C7	124.45 (17)	C26—C25—C24	121.29 (16)
C9—C8—H8A	117.8	C26—C25—H25A	119.4
C7—C8—H8A	117.8	C24—C25—H25A	119.4
C8—C9—C10	127.57 (17)	C25—C26—C21	121.83 (16)
C8—C9—H9A	116.2	C25—C26—H26A	119.1
C10—C9—H9A	116.2	C21—C26—H26A	119.1
C11—C10—C15	116.11 (16)	N3—C27—H27A	109.5
C11—C10—C9	120.27 (17)	N3—C27—H27B	109.5
C15—C10—C9	123.61 (16)	H27A—C27—H27B	109.5
C12—C11—C10	122.56 (18)	N3—C27—H27C	109.5
C12—C11—H11A	118.7	H27A—C27—H27C	109.5
C10—C11—H11A	118.7	H27B—C27—H27C	109.5
C11—C12—C13	120.82 (17)	N3—C28—H28A	109.5
C11—C12—H12A	119.6	N3—C28—H28B	109.5
C13—C12—H12A	119.6	H28A—C28—H28B	109.5
N2—C13—C12	121.37 (18)	N3—C28—H28C	109.5
N2—C13—C14	121.19 (19)	H28A—C28—H28C	109.5
C12—C13—C14	117.43 (16)	H28B—C28—H28C	109.5
C6—N1—C2—C3	62.35 (18)	C17—N2—C13—C14	3.3 (3)
C1—N1—C2—C3	−175.09 (14)	C11—C12—C13—N2	−177.01 (18)
N1—C2—C3—C7	156.21 (16)	C11—C12—C13—C14	2.2 (3)
N1—C2—C3—C4	−25.4 (2)	N2—C13—C14—C15	177.76 (19)
C7—C3—C4—O1	−7.1 (2)	C12—C13—C14—C15	−1.4 (3)
C2—C3—C4—O1	174.47 (15)	C13—C14—C15—C10	0.0 (3)
C7—C3—C4—C5	171.84 (15)	C11—C10—C15—C14	0.8 (3)
C2—C3—C4—C5	−6.6 (2)	C9—C10—C15—C14	−179.09 (18)
O1—C4—C5—C18	2.8 (3)	C4—C5—C18—C19	173.60 (16)
C3—C4—C5—C18	−176.18 (15)	C6—C5—C18—C19	−5.2 (3)
O1—C4—C5—C6	−178.38 (16)	C5—C18—C19—C20	179.20 (18)
C3—C4—C5—C6	2.7 (2)	C18—C19—C20—C21	174.93 (17)
C2—N1—C6—C5	−66.31 (18)	C19—C20—C21—C22	−176.90 (18)
C1—N1—C6—C5	171.08 (14)	C19—C20—C21—C26	3.1 (3)
C18—C5—C6—N1	−148.28 (16)	C26—C21—C22—C23	−0.6 (3)
C4—C5—C6—N1	32.9 (2)	C20—C21—C22—C23	179.36 (16)
C4—C3—C7—C8	−177.30 (15)	C21—C22—C23—C24	1.1 (3)
C2—C3—C7—C8	1.1 (3)	C27—N3—C24—C23	−12.3 (3)
C3—C7—C8—C9	−178.77 (18)	C28—N3—C24—C23	−171.99 (18)
C7—C8—C9—C10	179.75 (17)	C27—N3—C24—C25	168.01 (17)
C8—C9—C10—C11	−179.98 (18)	C28—N3—C24—C25	8.3 (3)
C8—C9—C10—C15	−0.1 (3)	C22—C23—C24—N3	179.52 (16)
C15—C10—C11—C12	0.0 (3)	C22—C23—C24—C25	−0.8 (3)
C9—C10—C11—C12	179.86 (17)	N3—C24—C25—C26	179.66 (16)
C10—C11—C12—C13	−1.5 (3)	C23—C24—C25—C26	−0.1 (3)
C16—N2—C13—C12	−6.7 (3)	C24—C25—C26—C21	0.6 (3)
C17—N2—C13—C12	−177.5 (2)	C22—C21—C26—C25	−0.2 (3)
C16—N2—C13—C14	174.09 (19)	C20—C21—C26—C25	179.80 (17)

(II) 3,5-bis[3-(4-methoxyphenyl)prop-2-enylidene]-1-methyl-4-piperidone

Crystal data

C26H27NO3	Dx = 1.245 Mg m^−3
Mr = 401.49	Melting point: 454 K
Orthorhombic, Cmc21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2c -2	Cell parameters from 1276 reflections
a = 25.786 (2) Å	θ = 4–27°
b = 10.0852 (8) Å	µ = 0.08 mm^−1
c = 8.2389 (7) Å	T = 173 K
V = 2142.6 (3) Å^3	Plate, yellow
Z = 4	0.28 × 0.08 × 0.02 mm
F(000) = 856

Data collection

Bruker SMART APEX CCD area-detector diffractometer	1632 independent reflections
Radiation source: fine-focus sealed tube	1315 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.042
ϕ and ω scans	θmax = 29.6°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1995)	h = −35→35
Tmin = 0.908, Tmax = 0.998	k = −14→14
15636 measured reflections	l = −11→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.097	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.043P)^2 + 0.52P] where P = (Fo^2 + 2Fc^2)/3
1632 reflections	(Δ/σ)max < 0.001
151 parameters	Δρmax = 0.15 e Å^−3
1 restraint	Δρmin = −0.16 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.5000	0.2539 (3)	0.1129 (3)	0.0692 (8)
O2	0.10040 (5)	0.11630 (17)	0.3567 (2)	0.0630 (5)
N1	0.5000	0.0768 (3)	0.5560 (3)	0.0459 (6)
C1	0.5000	0.2090 (4)	0.6277 (5)	0.0616 (9)
C2	0.45385 (7)	0.0515 (2)	0.4582 (3)	0.0479 (5)
H2A	0.4228	0.0686	0.5256	0.057*
H2B	0.4534	−0.0433	0.4272	0.057*
C3	0.45038 (7)	0.1347 (2)	0.3059 (3)	0.0430 (5)
C4	0.5000	0.1803 (3)	0.2309 (4)	0.0479 (7)
C5	0.40577 (7)	0.1682 (2)	0.2331 (3)	0.0439 (5)
H5A	0.4085	0.2223	0.1391	0.053*
C6	0.35380 (7)	0.1309 (2)	0.2821 (3)	0.0449 (5)
H6A	0.3495	0.0717	0.3708	0.054*
C7	0.31173 (7)	0.1771 (2)	0.2063 (3)	0.0459 (5)
H7A	0.3179	0.2330	0.1155	0.055*
C8	0.25727 (7)	0.1523 (2)	0.2461 (3)	0.0407 (4)
C9	0.21971 (7)	0.2388 (2)	0.1855 (3)	0.0478 (5)
H9A	0.2299	0.3093	0.1159	0.057*
C10	0.16795 (8)	0.2240 (2)	0.2249 (3)	0.0523 (5)
H10A	0.1431	0.2848	0.1838	0.063*
C11	0.15230 (7)	0.1210 (2)	0.3240 (3)	0.0447 (5)
C12	0.18862 (7)	0.0318 (2)	0.3823 (3)	0.0465 (5)
H12A	0.1780	−0.0405	0.4482	0.056*
C13	0.24049 (8)	0.04859 (19)	0.3441 (3)	0.0450 (5)
H13A	0.2652	−0.0123	0.3860	0.054*
C14	0.08131 (9)	0.0116 (4)	0.4551 (5)	0.0780 (9)
H14A	0.0440	0.0237	0.4730	0.117*
H14B	0.0994	0.0122	0.5597	0.117*
H14C	0.0873	−0.0733	0.4005	0.117*
H1A	0.4677 (9)	0.218 (2)	0.691 (4)	0.069 (8)*
H1B	0.5000	0.286 (4)	0.556 (6)	0.073 (12)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0409 (12)	0.0873 (19)	0.0795 (19)	0.000	0.000	0.0403 (16)
O2	0.0359 (7)	0.0801 (11)	0.0730 (12)	0.0018 (7)	0.0051 (8)	0.0083 (11)
N1	0.0350 (11)	0.0578 (14)	0.0449 (14)	0.000	0.000	0.0008 (12)
C1	0.059 (2)	0.067 (2)	0.059 (2)	0.000	0.000	−0.0083 (19)
C2	0.0324 (9)	0.0606 (13)	0.0505 (12)	−0.0020 (9)	0.0001 (9)	0.0063 (11)
C3	0.0342 (9)	0.0478 (11)	0.0469 (12)	0.0008 (8)	0.0016 (9)	0.0004 (9)
C4	0.0347 (14)	0.0553 (17)	0.0539 (18)	0.000	0.000	0.0064 (17)
C5	0.0349 (9)	0.0496 (11)	0.0472 (11)	0.0019 (8)	0.0012 (9)	0.0013 (10)
C6	0.0346 (9)	0.0538 (11)	0.0463 (12)	0.0007 (8)	−0.0011 (9)	−0.0002 (10)
C7	0.0370 (10)	0.0553 (12)	0.0454 (12)	−0.0012 (9)	0.0005 (9)	0.0036 (10)
C8	0.0331 (9)	0.0493 (11)	0.0397 (10)	−0.0007 (8)	−0.0028 (8)	−0.0015 (9)
C9	0.0409 (10)	0.0545 (12)	0.0480 (12)	0.0000 (9)	−0.0041 (10)	0.0115 (10)
C10	0.0376 (10)	0.0620 (12)	0.0574 (13)	0.0080 (9)	−0.0070 (10)	0.0121 (12)
C11	0.0326 (9)	0.0551 (11)	0.0463 (12)	−0.0015 (8)	−0.0008 (9)	−0.0028 (10)
C12	0.0441 (10)	0.0459 (11)	0.0495 (12)	−0.0029 (8)	0.0005 (10)	0.0025 (10)
C13	0.0393 (10)	0.0465 (11)	0.0493 (12)	0.0044 (8)	−0.0051 (9)	0.0026 (10)
C14	0.0511 (12)	0.0774 (17)	0.106 (2)	−0.0058 (15)	0.0254 (16)	0.0077 (18)

Geometric parameters (Å, º)

O1—C4	1.223 (4)	C6—H6A	0.9500
O2—C11	1.366 (2)	C7—C8	1.464 (3)
O2—C14	1.419 (4)	C7—H7A	0.9500
N1—C2	1.459 (3)	C8—C13	1.391 (3)
N1—C2^i	1.459 (3)	C8—C9	1.396 (3)
N1—C1	1.458 (5)	C9—C10	1.382 (3)
C1—H1A	0.99 (3)	C9—H9A	0.9500
C1—H1B	0.98 (5)	C10—C11	1.381 (3)
C2—C3	1.512 (3)	C10—H10A	0.9500
C2—H2A	0.9900	C11—C12	1.384 (3)
C2—H2B	0.9900	C12—C13	1.384 (3)
C3—C5	1.340 (3)	C12—H12A	0.9500
C3—C4	1.493 (3)	C13—H13A	0.9500
C4—C3^i	1.494 (3)	C14—H14A	0.9800
C5—C6	1.449 (3)	C14—H14B	0.9800
C5—H5A	0.9500	C14—H14C	0.9800
C6—C7	1.336 (3)
C11—O2—C14	118.56 (18)	C6—C7—H7A	116.0
C2—N1—C2^i	109.3 (3)	C8—C7—H7A	116.0
C2—N1—C1	112.53 (17)	C13—C8—C9	117.52 (17)
C2^i—N1—C1	112.53 (17)	C13—C8—C7	123.86 (18)
N1—C1—H1A	107.5 (15)	C9—C8—C7	118.60 (19)
N1—C1—H1B	119 (3)	C10—C9—C8	121.2 (2)
H1A—C1—H1B	104 (2)	C10—C9—H9A	119.4
N1—C2—C3	114.17 (19)	C8—C9—H9A	119.4
N1—C2—H2A	108.7	C11—C10—C9	120.15 (19)
C3—C2—H2A	108.7	C11—C10—H10A	119.9
N1—C2—H2B	108.7	C9—C10—H10A	119.9
C3—C2—H2B	108.7	O2—C11—C10	115.37 (18)
H2A—C2—H2B	107.6	O2—C11—C12	124.89 (19)
C5—C3—C4	118.2 (2)	C10—C11—C12	119.74 (18)
C5—C3—C2	124.18 (19)	C11—C12—C13	119.70 (19)
C4—C3—C2	117.61 (18)	C11—C12—H12A	120.1
O1—C4—C3	121.05 (14)	C13—C12—H12A	120.1
O1—C4—C3^i	121.05 (14)	C12—C13—C8	121.62 (18)
C3—C4—C3^i	117.9 (3)	C12—C13—H13A	119.2
C3—C5—C6	127.1 (2)	C8—C13—H13A	119.2
C3—C5—H5A	116.4	O2—C14—H14A	109.5
C6—C5—H5A	116.4	O2—C14—H14B	109.5
C7—C6—C5	122.0 (2)	H14A—C14—H14B	109.5
C7—C6—H6A	119.0	O2—C14—H14C	109.5
C5—C6—H6A	119.0	H14A—C14—H14C	109.5
C6—C7—C8	127.9 (2)	H14B—C14—H14C	109.5
C2^i—N1—C2—C3	−58.7 (3)	C6—C7—C8—C9	161.0 (2)
C1—N1—C2—C3	67.1 (3)	C13—C8—C9—C10	1.6 (3)
N1—C2—C3—C5	−153.0 (2)	C7—C8—C9—C10	−177.1 (2)
N1—C2—C3—C4	28.0 (3)	C8—C9—C10—C11	−1.0 (4)
C5—C3—C4—O1	5.1 (4)	C14—O2—C11—C10	178.8 (3)
C2—C3—C4—O1	−175.9 (3)	C14—O2—C11—C12	−1.2 (4)
C5—C3—C4—C3^i	−175.76 (18)	C9—C10—C11—O2	179.3 (2)
C2—C3—C4—C3^i	3.3 (4)	C9—C10—C11—C12	−0.7 (3)
C4—C3—C5—C6	177.8 (2)	O2—C11—C12—C13	−178.4 (2)
C2—C3—C5—C6	−1.2 (4)	C10—C11—C12—C13	1.6 (3)
C3—C5—C6—C7	175.6 (2)	C11—C12—C13—C8	−0.9 (3)
C5—C6—C7—C8	−177.4 (2)	C9—C8—C13—C12	−0.7 (3)
C6—C7—C8—C13	−17.6 (4)	C7—C8—C13—C12	177.9 (2)

Symmetry code: (i) −x+1, y, z.