A host–guest 1:2 inclusion compound of 1,1,6,6-tetra­phenyl­hexa-2,4-diyne-1,6-diol and 4-methoxy­benz­aldehyde

The inclusion method was used to isolate a single component from a volatile oil mixture (extracted from the natural medicine, fructus foeniculi) with 1,1,6,6-tetra­phenyl­hexa-2,4-diyne-1,6-diol as the host mol­ecule and 4-methoxy­benz­aldehyde as the guest (an oil mixture component). Crystals of the host–guest inclusion complex were obtained as C₃₀H₂₂O₂·2C₈H₈O₂, with the host mol­ecule residing on a crystallographic inversion centre and connected to the guest mol­ecule by an intermolecular hydrogen bond [O...O = 2.846 (5) Å]. The host–guest mol­ecules form a layer-type structure, which extends along the a axis and periodically arranges along the b axis.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.058
• wR factor = 0.124
• Data-to-parameter ratio = 13.2

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level A:



DIFF_019  Alert A _diffrn_standards_number is missing
          Number of standards used in measurement.

Author response: Our diffractometer collect data with the area-detector. Diffraction standards are not needed.

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 Alert Level C:



PLAT_373  Alert C Long   C(sp)-C(sp)   Bond  C(15)  -   C(15)a =       1.39 Ang.


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S1. Comment

An important direction for pharmaceutical research is to achieve bioactive leading compounds from natural products. Volatile oils exist in many natural products and they have important implications in pharmacodynamics research. Most of these oils belong to monoterpenoids, sesquiterpenoids and aromatic compounds, and they have functional groups such as alcohol, aldehyde, ketone and lactone. The similarity in chemical structure and volatility makes it more difficult to extract and isolate components from the mother oil.

The inclusion method used by us depends on two essential factors: (i) the similar geometric topology and (ii) intermolecular hydrogen bond/van der Waals forces between the host–guest molecules (Lehn, 1988). We chose 4-methoxybenzaldehyde (anisaldehyde) in the volatile oil mixture as the guest molecule, which has bioactivity such as antifungal (Sun & Sheng, 1998), and selected 1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol as the host molecule, which can include many guest molecules, such as alcohol, aldehyde, ketone and lactone (Takumi et al., 1996). We obtained a crystal of the 1:2 host–guest 1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol–4-methoxybenzaldehyde (1/2), (I).

In (I), the inversion centre of the host molecule matches with the crystallographic inversion centre (1/2,0,0) (Fig. 1). An asymmetric unit includes half of the host molecule and one guest molecule, viz. in a 1:2 ratio. With van der Waals forces, the host–guest molecules form a level-like tunnel structure, which extends along the a and c axes and periodically arranges along the b axis (Fig. 2). The guest molecule is planar, as expected. The hydroxyl group of the host molecule is associated with the aldehyde group of the guest molecule (details in Table 1).

S2. Experimental

Fructus foeniculi (100 g) was ground and distilled with water vapor. The volatile oil was dehydrated with anhydrous Na₂SO₄ and 2 g of material was obtained. 1,1,6,6-Tetraphenylhexa-2,4-diyne-1,6-diol (0.2 g) was added to a 10 ml conical flask and dissolved in ethyl ether (0.6 ml). The volatile oil (0.3 g) and petroleum ether (1 ml) were added to the host solution and the resulting solution stored at 298 K. After the crystals were found, recrystallization was under the same conditions and the title host–guest inclusion complex was obtained.

Computing details

Data collection: DENZO (MacScience, 1996); cell refinement: SCALE (MacScience, 1996); data reduction: SCALE; program(s) used to solve structure: SHELXS90 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976) and PLUTON (Spek, 1990).

Figures

	Fig. 1. The molecular structure of inclusion complex (I), showing 50% probability displacement ellipsoids [symmetry code: (i) 1 − x, −y, −z]. H atoms have been omitted for clarity.
	Fig. 2. The packing viewed down the c axis. The black atoms are O atoms which form hydrogen bonds.

1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol–4-methoxybenzaldehyde (1/2)

Crystal data

C30H22O2·2C8H8O2	F(000) = 724
Mr = 686.80	Dx = 1.244 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3223 reflections
a = 8.593 (1) Å	θ = 2–25°
b = 18.181 (1) Å	µ = 0.08 mm^−1
c = 12.649 (1) Å	T = 296 K
β = 111.38 (1)°	Block, pale yellow
V = 1840.2 (3) Å^3	0.40 × 0.30 × 0.22 mm
Z = 2

Data collection

MAC DIP 2030K diffractometer	3101 reflections with F^2 ≥ 2σ(F^2)
Radiation source: rotate anode	Rint = 0.032
Graphite monochromator	θmax = 25.0°, θmin = 0.0°
ω scans	h = 0→11
5896 measured reflections	k = −21→20
3223 independent reflections	l = −16→15

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	H-atom parameters not refined
R[F^2 > 2σ(F^2)] = 0.058	w = 1/[σ^2(Fo^2) + (0.1082P)^2 + 0.627P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.124	(Δ/σ)max = 0.007
S = 1.46	Δρmax = 0.12 e Å^−3
3101 reflections	Δρmin = −0.28 e Å^−3
235 parameters

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

	x	y	z	Uiso*/Ueq
O1	0.7685 (2)	0.1736 (1)	0.1652 (1)	0.042 (1)
C1	0.9789 (3)	0.0771 (1)	0.2107 (2)	0.034 (1)
C2	1.0160 (3)	0.0206 (1)	0.1511 (2)	0.042 (1)
C3	1.1818 (4)	0.0069 (2)	0.1631 (3)	0.053 (2)
C4	1.3084 (4)	0.0496 (2)	0.2351 (3)	0.056 (2)
C5	1.2721 (4)	0.1055 (2)	0.2960 (3)	0.053 (2)
C6	1.1088 (3)	0.1196 (1)	0.2842 (2)	0.042 (1)
C7	0.7995 (3)	0.0978 (1)	0.1979 (2)	0.034 (1)
C8	0.7758 (3)	0.0874 (1)	0.3114 (2)	0.034 (1)
C9	0.7848 (4)	0.0169 (1)	0.3552 (3)	0.047 (2)
C10	0.7641 (4)	0.0054 (2)	0.4572 (3)	0.058 (2)
C11	0.7351 (4)	0.0639 (2)	0.5165 (3)	0.061 (2)
C12	0.7264 (4)	0.1340 (2)	0.4738 (3)	0.057 (2)
C13	0.7481 (4)	0.1461 (2)	0.3712 (2)	0.046 (2)
C14	0.6725 (3)	0.0523 (2)	0.1101 (2)	0.036 (1)
C15	0.5635 (3)	0.0193 (1)	0.0406 (2)	0.037 (1)
O2	0.3304 (3)	0.1737 (1)	0.6777 (2)	0.069 (2)
O3	−0.1216 (3)	0.1844 (1)	0.9791 (2)	0.069 (2)
C16	0.2685 (4)	0.1764 (2)	0.7627 (3)	0.051 (2)
C17	0.0950 (4)	0.1753 (2)	0.7255 (3)	0.049 (2)
C18	0.0170 (4)	0.1781 (1)	0.8024 (3)	0.048 (1)
C19	0.1100 (4)	0.1817 (1)	0.9185 (3)	0.049 (2)
C20	0.2831 (5)	0.1821 (2)	0.9535 (3)	0.063 (2)
C21	0.3631 (4)	0.1796 (2)	0.8769 (3)	0.062 (2)
C22	0.5064 (5)	0.1680 (3)	0.7063 (4)	0.075 (4)
C23	0.0290 (5)	0.1844 (2)	1.0012 (3)	0.063 (2)
H1	0.798	0.182	0.110	0.049
H2	0.925	−0.011	0.102	0.050
H3	1.207	−0.033	0.119	0.061
H4	1.424	0.040	0.243	0.063
H5	1.363	0.136	0.348	0.060
H6	1.083	0.159	0.328	0.049
H9	0.807	−0.025	0.313	0.056
H10	0.770	−0.045	0.488	0.064
H11	0.722	0.057	0.589	0.068
H12	0.704	0.175	0.516	0.066
H13	0.744	0.197	0.341	0.054
H17	0.029	0.172	0.643	0.058
H18	−0.106	0.178	0.776	0.058
H20	0.349	0.184	1.035	0.067
H21	0.486	0.180	0.904	0.066
H22	0.558	0.215	0.731	0.085
H23	0.530	0.151	0.642	0.085
H24	0.540	0.133	0.766	0.085
H25	0.103	0.186	1.082	0.071

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.056 (1)	0.048 (1)	0.052 (1)	0.004 (1)	0.019 (1)	0.005 (1)
C1	0.036 (1)	0.049 (2)	0.040 (2)	−0.004 (1)	0.009 (1)	0.004 (1)
C2	0.046 (2)	0.059 (2)	0.050 (2)	0.001 (1)	0.013 (1)	−0.002 (2)
C3	0.057 (2)	0.082 (3)	0.066 (2)	0.018 (2)	0.025 (2)	0.004 (2)
C4	0.039 (2)	0.099 (3)	0.075 (2)	0.009 (2)	0.020 (2)	0.021 (2)
C5	0.039 (2)	0.083 (3)	0.069 (2)	−0.012 (2)	0.007 (2)	0.008 (2)
C6	0.043 (2)	0.058 (2)	0.051 (2)	−0.004 (1)	0.008 (1)	0.001 (2)
C7	0.036 (2)	0.042 (2)	0.044 (2)	−0.003 (1)	0.008 (1)	−0.002 (1)
C8	0.032 (1)	0.057 (2)	0.036 (1)	−0.005 (1)	0.007 (1)	−0.004 (1)
C9	0.063 (2)	0.063 (2)	0.051 (2)	0.001 (2)	0.020 (1)	0.004 (2)
C10	0.076 (2)	0.084 (3)	0.057 (2)	−0.004 (2)	0.021 (2)	0.018 (2)
C11	0.071 (2)	0.116 (3)	0.047 (2)	−0.016 (2)	0.022 (2)	−0.001 (2)
C12	0.069 (2)	0.098 (3)	0.051 (2)	−0.011 (2)	0.025 (2)	−0.021 (2)
C13	0.057 (2)	0.065 (2)	0.051 (2)	−0.007 (2)	0.018 (2)	−0.009 (2)
C14	0.036 (2)	0.055 (2)	0.043 (2)	0.001 (1)	0.012 (1)	0.001 (1)
C15	0.036 (1)	0.058 (2)	0.042 (2)	−0.002 (1)	0.009 (1)	−0.001 (1)
O2	0.068 (2)	0.099 (2)	0.103 (2)	−0.001 (1)	0.043 (2)	−0.003 (2)
O3	0.117 (2)	0.082 (2)	0.079 (2)	0.018 (2)	0.052 (2)	0.021 (1)
C16	0.064 (2)	0.051 (2)	0.077 (2)	0.003 (2)	0.025 (2)	0.002 (2)
C17	0.055 (2)	0.066 (2)	0.058 (2)	0.001 (2)	0.013 (2)	0.002 (2)
C18	0.058 (2)	0.058 (2)	0.065 (2)	0.004 (2)	0.020 (2)	0.009 (2)
C19	0.081 (2)	0.048 (2)	0.054 (2)	0.005 (2)	0.019 (2)	0.009 (2)
C20	0.085 (3)	0.073 (3)	0.058 (2)	0.001 (2)	0.001 (2)	0.006 (2)
C21	0.058 (2)	0.078 (3)	0.084 (3)	0.003 (2)	0.008 (2)	0.006 (2)
C22	0.074 (2)	0.100 (2)	0.118 (2)	−0.003 (2)	0.046 (2)	−0.009 (2)
C23	0.119 (3)	0.059 (2)	0.060 (2)	0.004 (2)	0.031 (2)	0.013 (2)

Geometric parameters (Å, º)

O1—C7	1.436 (3)	C11—H11	0.978
O1—H1	0.841	C12—C13	1.394 (4)
C1—C2	1.379 (4)	C12—H12	0.980
C1—C6	1.397 (4)	C13—H13	0.990
C1—C7	1.537 (4)	C14—C15	1.187 (4)
C2—C3	1.398 (4)	O2—C16	1.364 (4)
C2—H2	0.982	O2—C22	1.424 (5)
C3—C4	1.376 (5)	O3—C23	1.220 (5)
C3—H3	0.988	C16—C17	1.390 (4)
C4—C5	1.378 (5)	C16—C21	1.376 (5)
C4—H4	0.980	C17—C18	1.369 (5)
C5—C6	1.380 (4)	C17—H17	0.987
C5—H5	0.981	C18—C19	1.395 (4)
C6—H6	0.982	C18—H18	0.984
C7—C8	1.534 (4)	C19—C20	1.389 (5)
C7—C14	1.491 (4)	C19—C23	1.453 (5)
C8—C9	1.388 (4)	C20—C21	1.379 (6)
C8—C13	1.379 (4)	C20—H20	0.980
C9—C10	1.382 (4)	C21—H21	0.984
C9—H9	0.991	C22—H22	0.957
C10—C11	1.376 (6)	C22—H23	0.958
C10—H10	0.991	C22—H24	0.957
C11—C12	1.375 (6)	C23—H25	0.987
C7—O1—H1	108.9	C12—C11—H11	119.3
C2—C1—C6	119.2 (3)	C11—C12—C13	120.3 (3)
C2—C1—C7	123.2 (2)	C11—C12—H12	119.5
C6—C1—C7	117.5 (3)	C13—C12—H12	120.1
C1—C2—C3	120.2 (3)	C8—C13—C12	119.8 (3)
C1—C2—H2	119.1	C8—C13—H13	119.6
C3—C2—H2	120.7	C12—C13—H13	120.6
C2—C3—C4	120.0 (3)	C7—C14—C15	175.6 (3)
C2—C3—H3	119.5	C16—O2—C22	119.0 (3)
C4—C3—H3	120.4	O2—C16—C17	114.2 (3)
C3—C4—C5	120.0 (3)	O2—C16—C21	125.3 (3)
C3—C4—H4	119.7	C17—C16—C21	120.4 (3)
C5—C4—H4	120.3	C16—C17—C18	120.1 (3)
C4—C5—C6	120.4 (3)	C16—C17—H17	119.6
C4—C5—H5	119.7	C18—C17—H17	120.3
C6—C5—H5	119.9	C17—C18—C19	120.6 (3)
C1—C6—C5	120.2 (3)	C17—C18—H18	120.1
C1—C6—H6	119.3	C19—C18—H18	119.3
C5—C6—H6	120.5	C18—C19—C20	118.2 (3)
O1—C7—C1	109.8 (2)	C18—C19—C23	121.2 (3)
O1—C7—C8	108.3 (2)	C20—C19—C23	120.6 (3)
O1—C7—C14	108.1 (2)	C19—C20—C21	121.8 (3)
C1—C7—C8	110.0 (2)	C19—C20—H20	118.3
C1—C7—C14	112.1 (2)	C21—C20—H20	120.0
C8—C7—C14	108.5 (2)	C16—C21—C20	118.9 (4)
C7—C8—C9	118.7 (3)	C16—C21—H21	120.6
C7—C8—C13	121.8 (3)	C20—C21—H21	120.5
C9—C8—C13	119.4 (3)	O2—C22—H22	110.1
C8—C9—C10	120.3 (3)	O2—C22—H23	110.0
C8—C9—H9	119.2	O2—C22—H24	103.7
C10—C9—H9	120.5	H22—C22—H23	109.9
C9—C10—C11	120.2 (3)	H22—C22—H24	111.5
C9—C10—H10	120.2	H23—C22—H24	111.5
C11—C10—H10	119.6	O3—C23—C19	125.5 (3)
C10—C11—C12	119.8 (3)	O3—C23—H25	117.7
C10—C11—H11	120.9	C19—C23—H25	116.8

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O3^i	0.84	2.01	2.846 (5)	171

Symmetry code: (i) x+1, y, z−1.