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A novel binucleating 24-membered macrocyclic ligand, 6,20-bis(2-hydroxy­ethyl)-3,6,9,17,20,23-hex­aza­tri­cyclo­[23.3.1.111,15]triaconta-1(29),11(30),12,14,25,27-hexaene (L), was synthesized and crystallized as the tetra­hydro­bromide salt, i.e. 6,20-bis(2-hydroxy­ethyl)-6,20-di­aza-3,9,17,23-hexa­azoniatri­cyclo­[23.3.1.111,15]­triaconta-1(29),11(30),­12,14,25,27-hexaene tetrabromide tetrahydrate, C28H50N6O24+·­4Br-·4H2O. A crystallographic inversion center is located in the macrocyclic cavity and the two hydroxy­ethyl pendants are on opposite sides of the macrocyclic plane. The benzene rings of the macrocycle are parallel to each other and a [pi]-[pi]-stacking interaction exists between the benzene rings of adjacent macrocycles, which are separated by 3.791 (9) Å. An infinite intermolecular hydrogen-bond network stabilizes the crystal.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270101016146/ta1341sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270101016146/ta1341Isup2.hkl
Contains datablock I

CCDC reference: 180153

Comment top

The design and synthesis of new macrocyclic polyaza ligands are of great current interest. The cavity, rigidity, and donor type of a macrocycle are all important in governing the host–guest interaction, the selectivity of metal ions and the construction of model compounds of the active site of enzymes (Shangguan et al., 2000; Lu et al., 1995). In particular, the incorporation of functionalized pendant coordinating arms on macrocyclic polyaza compounds can provide additional coordinating functions and hence enhance the complexing stability. A few macrocycles with pendants have been reported previously. However, the synthesis of dinucleating macrocyclic ligands with hydroxyethyl pendants is rare (Kimura et al., 2000; Bazzicalupi et al., 1999). In this article, we report the structure of a novel 24-membered macrocyclic ligand with two hydroxyethyl pendants as its tetrahydrated tetrahydrobromide salt, i.e. 6,20-bis(2-hydroxyethyl)-6,20-diaza-3,9,17,23-hexaazoniatricyclo- [23.3.1.1.11,15]triaconta-1(29),11 (30),12,14,25,27-hexaene tetrabromide tetrahydrate, (H4L)Br4·4H2O, (I).

The macrocycle adopts a chair conformation with a crystallographic inversion center located in the macrocyclic cavity (Fig. 1). The four secondary N atoms are coplanar, while the tertiary N atoms deviate by 0.379 (8) Å from the macrocyclic plane, one up and one down. The benzene rings are tilted at angles of 36.9 (2)° to macrocyclic least-squares plane and are parallel to one another, at a distance of 8.835 (9) Å. The two hydroxyethyl pendants appear on opposite sides of the macrocyclic plane and the distance between the two O atoms is 10.57 (1) Å. The structure of this compound is quite different from that of the hexahydrobromide salt of a similar macrocyclic compound BMXD, which is L without the hydroxyethyl pendants (Nation et al., 1996). In H6BMXDBr6·7H2O, the six N atoms are approximately planar and the three N atoms of each diethylenetriamine unit are in a linear arrangement. The difference is due to the the incorporation of the two hydroxyethyl pendants into the macrocycle. Furthermore, the two tertiary amine N atoms of (H4L)4+ are not protonated and the distance between them is 9.686 (9) Å, which is much longer than the distance of 6.35 (2) Å between the two secondary amines N atoms in H6BMXDBr6·7H2O.

The four secondary amine N atoms in the macrocycle are protonated. The tertiary amine N atoms are not protonated, indicating that they are of weak bascity. The four bromide counter-ions and the four water molecules are bound to the protonated amines and hydroxyethyl O atoms through hydrogen bonds (Table 2). Only two bromide counter-ions and two water molecules are encapsulated in the macrocyclic cavity. Inside each macrocycle, O2W forms hydrogen bonds with N1 and N2, and the hydroxyethyl O1 atom forms a hydrogen bond with N2. The Br1 atom forms hydrogen bonds separately with N1 and N2 of two adjacent macrocyclic rings, and simultaneously forms a hydrogen bond with O2W, which is responsible for the formation of a one-dimensional quasi-chain structure along the b axis, as shown in Fig. 2. The hydrogen bond between Br2 and the hydroxyethyl O1 atom, together with that between Br2 and O1W, links the chains into a two-dimensional network, as shown in Fig. 3. In addition, Fig. 2 also reveals that the two-dimensional structures are connected into an infinite three-dimensional structure (Fig. 3) through ππ-stacking interactions between the adjacent benzene rings of two one-dimensional quasi-chain elements with a nearest distance of 3.791 (9) Å. All the Br···N and Br···O distances in all contacts are typical for hydrogen-bonding interactions and range from 2.756 (7) to 3.358 (5) Å.

Experimental top

A solution of isophthalic aldehyde (0.804 g, 0.006 mol) in CH3CN (100 ml)was added dropwise to a solution of 2-[bis(2-aminoethyl)amino]ethanol (0.882 g, 0.006 mol) in CH3CN (150 ml) under magnetic stirring over 8 h at 273 K and a white suspension appeared. After stirring for another 12 h, a white microcrystalline solid precipitated and was filtered off and washed with ether. The microcrystals were dissolved in EtOH (100 ml) at 318 K and NaBH4 (2.5 g) was added little by little over a period of 3 h under stirring. After removing the solvent under reduced pressure, H2O (5 ml) and CH2Cl2 (100 ml) were added sequentially to extract the product. A colorless viscous oil was obtained after removing CH2Cl2 from the organic phase. Several hours after the addition of 48% HBr (5 ml) to the product at 273 K, white microcrystals appeared in a yield of 1.61 g (60%). A crystal suitable for X-ray analysis was obtained by evaporation of an aqueous solution of the microcrystal. Elemental analysis, calculated for for L·4HBr·4H2O (C28H58Br4N6O6): C 37.6, H 6.48, N 9.39%; found: C 37.5, H 6.36, N 9.28%.

Refinement top

All H atoms on C atoms in the macrocycle were geometrically fixed (C—H = 0.93 and 0.97 Å), and N—H and O—H atoms were located according to a difference electron-density calculation (see Table 2 for N—H and O—H bond lengths).

Computing details top

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: SHELXTL/PC (Sheldrick, 1990); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC; software used to prepare material for publication: SHELXTL/PC.

Figures top
[Figure 1] Fig. 1. The structure of (I) showing 30% probability displacemnt ellipsoids.
[Figure 2] Fig. 2. A view of the one-dimensional quasi-chain structure formed through hydrogen bonds along the b axis.
[Figure 3] Fig. 3. Packing arrangement of L·4HBr·4H2O showing hydrogen bonds and ππ-stacking interactions.
6,20-bis(2-hydroxyethyl)-6,20-diaza-3,9,17,23-hexaazoniatricyclo- [23.3.1.1.11,15]triaconta-1(29),11 (30),12,14,25,27-hexaene tetrabromide tetrahydrate top
Crystal data top
C28H50N6O24+·4Br·4H2OF(000) = 912
Mr = 894.44Dx = 1.552 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 10.179 (4) ÅCell parameters from 32 reflections
b = 7.933 (2) Åθ = 5.0–14.3°
c = 23.776 (6) ŵ = 4.25 mm1
β = 94.244 (19)°T = 293 K
V = 1914.6 (11) Å3Block, colorless
Z = 20.3 × 0.3 × 0.2 mm
Data collection top
Bruker P4
diffractometer
1991 reflections with I > 2σ(I)
Radiation source: sealed tubeRint = 0.087
Graphite monochromatorθmax = 25.0°, θmin = 2.1°
2θ/ω scansh = 112
Absorption correction: empirical (using intensity measurements)
(North et al., 1968)
k = 19
Tmin = 0.292, Tmax = 0.437l = 2828
4531 measured reflections3 standard reflections every 97 reflections
3335 independent reflections intensity decay: 14.6%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0501P)2 + 0.687P]
where P = (Fo2 + 2Fc2)/3
3335 reflections(Δ/σ)max < 0.001
221 parametersΔρmax = 0.66 e Å3
0 restraintsΔρmin = 0.72 e Å3
Crystal data top
C28H50N6O24+·4Br·4H2OV = 1914.6 (11) Å3
Mr = 894.44Z = 2
Monoclinic, P21/nMo Kα radiation
a = 10.179 (4) ŵ = 4.25 mm1
b = 7.933 (2) ÅT = 293 K
c = 23.776 (6) Å0.3 × 0.3 × 0.2 mm
β = 94.244 (19)°
Data collection top
Bruker P4
diffractometer
1991 reflections with I > 2σ(I)
Absorption correction: empirical (using intensity measurements)
(North et al., 1968)
Rint = 0.087
Tmin = 0.292, Tmax = 0.4373 standard reflections every 97 reflections
4531 measured reflections intensity decay: 14.6%
3335 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.66 e Å3
3335 reflectionsΔρmin = 0.72 e Å3
221 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
C10.2343 (5)0.7349 (7)0.4792 (2)0.0370 (13)
H10.32420.74890.48810.044*
C20.1912 (5)0.6634 (7)0.4274 (3)0.0391 (14)
C30.0574 (6)0.6465 (8)0.4130 (3)0.0538 (17)
H30.02760.60380.37790.065*
C40.0310 (6)0.6939 (9)0.4513 (3)0.065 (2)
H40.12070.67870.44240.078*
C50.0119 (6)0.7638 (8)0.5028 (3)0.0492 (16)
H50.04920.79670.52780.059*
C60.1471 (5)0.7853 (7)0.5174 (3)0.0390 (14)
C70.1858 (6)0.8683 (9)0.5724 (3)0.0539 (18)
H7A0.14890.80460.60230.065*
H7B0.14750.98020.57220.065*
C80.3679 (6)0.9843 (8)0.6375 (3)0.0456 (16)
H8A0.33730.92680.67010.055*
H8B0.32501.09350.63440.055*
C90.5145 (6)1.0081 (7)0.6453 (3)0.0473 (16)
H9A0.54601.04560.60990.057*
H9B0.53331.09660.67290.057*
C100.5834 (6)0.8262 (8)0.7255 (3)0.0495 (17)
H10A0.54280.92340.74190.059*
H10B0.67300.81830.74230.059*
C110.5103 (6)0.6724 (8)0.7409 (3)0.0528 (17)
H11A0.50580.66760.78150.063*
H11B0.42110.67630.72350.063*
C120.2922 (6)0.6150 (7)0.3869 (3)0.0431 (15)
H12A0.25950.64710.34910.052*
H12B0.37240.67820.39630.052*
C130.2250 (5)0.3216 (7)0.3563 (3)0.0434 (15)
H13A0.20700.36290.31810.052*
H13B0.14330.32280.37490.052*
C140.2780 (6)0.1445 (8)0.3550 (3)0.0482 (16)
H14A0.27910.09550.39240.058*
H14B0.22100.07620.32970.058*
N10.3316 (5)0.8833 (6)0.5855 (2)0.0395 (12)
H1A0.35730.78050.58950.046 (19)*
H1B0.362 (5)0.935 (7)0.557 (2)0.043 (18)*
N20.3240 (5)0.4324 (6)0.3874 (2)0.0372 (12)
H2A0.404 (6)0.422 (7)0.367 (3)0.056*
H2B0.337 (6)0.400 (8)0.420 (3)0.056*
N30.5881 (4)0.8556 (6)0.66402 (19)0.0381 (11)
O10.5756 (5)0.5272 (6)0.7222 (2)0.0567 (13)
H20.537 (7)0.449 (9)0.735 (3)0.085*
Br10.38869 (6)0.22261 (8)0.50645 (2)0.0436 (2)
Br20.09066 (6)0.26580 (9)0.71653 (3)0.0544 (2)
O1W0.2326 (5)0.6091 (7)0.6741 (2)0.0658 (14)
H1WA0.18700.53310.68740.05 (2)*
H1WB0.28520.65320.69600.10 (4)*
O2W0.3896 (5)0.5394 (5)0.5985 (2)0.0490 (12)
H2WA0.345 (6)0.502 (8)0.624 (3)0.050*
H2WB0.397 (6)0.463 (8)0.577 (3)0.050*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.031 (3)0.044 (3)0.036 (3)0.004 (3)0.002 (2)0.002 (3)
C20.031 (3)0.043 (3)0.043 (4)0.002 (3)0.001 (3)0.007 (3)
C30.041 (4)0.059 (4)0.060 (4)0.002 (3)0.009 (3)0.010 (4)
C40.032 (3)0.068 (5)0.091 (6)0.003 (3)0.009 (4)0.022 (5)
C50.036 (3)0.057 (4)0.055 (4)0.005 (3)0.006 (3)0.004 (3)
C60.030 (3)0.043 (3)0.044 (4)0.001 (3)0.004 (3)0.004 (3)
C70.044 (4)0.065 (4)0.053 (4)0.013 (3)0.008 (3)0.002 (4)
C80.062 (4)0.037 (3)0.038 (4)0.002 (3)0.004 (3)0.002 (3)
C90.064 (4)0.036 (3)0.042 (4)0.006 (3)0.001 (3)0.002 (3)
C100.065 (4)0.049 (4)0.034 (4)0.004 (3)0.004 (3)0.004 (3)
C110.059 (4)0.056 (4)0.044 (4)0.010 (4)0.009 (3)0.005 (3)
C120.047 (4)0.041 (4)0.041 (4)0.003 (3)0.002 (3)0.001 (3)
C130.034 (3)0.053 (4)0.043 (4)0.008 (3)0.001 (3)0.006 (3)
C140.042 (4)0.047 (4)0.056 (4)0.014 (3)0.004 (3)0.008 (3)
N10.045 (3)0.036 (3)0.038 (3)0.003 (2)0.008 (2)0.002 (2)
N20.034 (3)0.045 (3)0.033 (3)0.008 (2)0.001 (2)0.006 (2)
N30.047 (3)0.036 (3)0.031 (3)0.003 (2)0.002 (2)0.002 (2)
O10.064 (3)0.050 (3)0.059 (3)0.003 (2)0.022 (2)0.007 (2)
Br10.0438 (3)0.0480 (4)0.0388 (4)0.0032 (3)0.0025 (3)0.0058 (3)
Br20.0519 (4)0.0598 (4)0.0516 (4)0.0028 (3)0.0050 (3)0.0040 (3)
O1W0.058 (3)0.076 (3)0.063 (3)0.006 (3)0.002 (3)0.005 (3)
O2W0.053 (3)0.041 (3)0.053 (3)0.001 (2)0.005 (2)0.006 (2)
Geometric parameters (Å, º) top
C1—C61.376 (8)C10—H10B0.9700
C1—C21.396 (8)C11—O11.417 (7)
C1—H10.9300C11—H11A0.9700
C2—C31.386 (8)C11—H11B0.9700
C2—C121.509 (8)C12—N21.485 (8)
C3—C41.379 (9)C12—H12A0.9700
C3—H30.9300C12—H12B0.9700
C4—C51.385 (10)C13—N21.491 (7)
C4—H40.9300C13—C141.506 (9)
C5—C61.405 (8)C13—H13A0.9700
C5—H50.9300C13—H13B0.9700
C6—C71.490 (9)C14—N3i1.467 (7)
C7—N11.498 (7)C14—H14A0.9700
C7—H7A0.9700C14—H14B0.9700
C7—H7B0.9700N1—H1A0.8596
C8—N11.496 (7)N1—H1B0.87 (6)
C8—C91.502 (8)N2—H2A0.99 (6)
C8—H8A0.9700N2—H2B0.82 (6)
C8—H8B0.9700N3—C14i1.467 (7)
C9—N31.474 (7)O1—H20.81 (7)
C9—H9A0.9700O1W—H1WA0.8374
C9—H9B0.9700O1W—H1WB0.8001
C10—N31.484 (7)O2W—H2WA0.84 (6)
C10—C111.489 (9)O2W—H2WB0.79 (6)
C10—H10A0.9700
C6—C1—C2121.7 (5)O1—C11—C10109.5 (5)
C6—C1—H1119.2O1—C11—H11A109.8
C2—C1—H1119.2C10—C11—H11A109.8
C3—C2—C1119.8 (6)O1—C11—H11B109.8
C3—C2—C12121.3 (6)C10—C11—H11B109.8
C1—C2—C12118.8 (5)H11A—C11—H11B108.2
C4—C3—C2119.1 (6)N2—C12—C2113.7 (5)
C4—C3—H3120.4N2—C12—H12A108.8
C2—C3—H3120.4C2—C12—H12A108.8
C3—C4—C5121.0 (6)N2—C12—H12B108.8
C3—C4—H4119.5C2—C12—H12B108.8
C5—C4—H4119.5H12A—C12—H12B107.7
C4—C5—C6120.5 (6)N2—C13—C14109.3 (5)
C4—C5—H5119.8N2—C13—H13A109.8
C6—C5—H5119.8C14—C13—H13A109.8
C1—C6—C5117.9 (6)N2—C13—H13B109.8
C1—C6—C7124.5 (5)C14—C13—H13B109.8
C5—C6—C7117.5 (5)H13A—C13—H13B108.3
C6—C7—N1114.3 (5)N3i—C14—C13110.4 (5)
C6—C7—H7A108.7N3i—C14—H14A109.6
N1—C7—H7A108.7C13—C14—H14A109.6
C6—C7—H7B108.7N3i—C14—H14B109.6
N1—C7—H7B108.7C13—C14—H14B109.6
H7A—C7—H7B107.6H14A—C14—H14B108.1
N1—C8—C9110.7 (5)C8—N1—C7113.2 (5)
N1—C8—H8A109.5C8—N1—H1A111.2
C9—C8—H8A109.5C7—N1—H1A103.7
N1—C8—H8B109.5C8—N1—H1B108 (4)
C9—C8—H8B109.5C7—N1—H1B106 (4)
H8A—C8—H8B108.1H1A—N1—H1B114.1
N3—C9—C8114.4 (5)C12—N2—C13115.6 (5)
N3—C9—H9A108.7C12—N2—H2A105 (3)
C8—C9—H9A108.7C13—N2—H2A105 (4)
N3—C9—H9B108.7C12—N2—H2B110 (5)
C8—C9—H9B108.7C13—N2—H2B110 (5)
H9A—C9—H9B107.6H2A—N2—H2B111 (6)
N3—C10—C11115.1 (5)C14i—N3—C9111.8 (5)
N3—C10—H10A108.5C14i—N3—C10113.7 (5)
C11—C10—H10A108.5C9—N3—C10111.9 (5)
N3—C10—H10B108.5C11—O1—H2105 (5)
C11—C10—H10B108.5H1WA—O1W—H1WB115.5
H10A—C10—H10B107.5H2WA—O2W—H2WB106 (7)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···Br20.842.463.277 (6)166
N1—H1A···O2W0.861.952.804 (6)172
N1—H1B···Br1ii0.87 (5)2.60 (5)3.358 (5)146 (5)
O1—H2···Br2iii0.81 (7)2.48 (7)3.279 (5)173 (6)
O1W—H1WB···Br2iv0.802.523.294 (5)165
N2—H2A···O1i0.98 (6)2.18 (7)2.886 (7)127 (5)
N2—H2A···O2Wi0.98 (6)2.22 (6)2.918 (7)127 (5)
N2—H2B···Br10.82 (7)2.51 (7)3.307 (5)164 (6)
O2W—H2WA···O1Wii0.84 (7)1.93 (7)2.756 (7)171 (7)
O2W—H2WB···Br10.80 (6)2.54 (7)3.332 (5)173 (6)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z; (iii) x+1/2, y+1/2, z+3/2; (iv) x+1/2, y1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC28H50N6O24+·4Br·4H2O
Mr894.44
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)10.179 (4), 7.933 (2), 23.776 (6)
β (°) 94.244 (19)
V3)1914.6 (11)
Z2
Radiation typeMo Kα
µ (mm1)4.25
Crystal size (mm)0.3 × 0.3 × 0.2
Data collection
DiffractometerBruker P4
diffractometer
Absorption correctionEmpirical (using intensity measurements)
(North et al., 1968)
Tmin, Tmax0.292, 0.437
No. of measured, independent and
observed [I > 2σ(I)] reflections
4531, 3335, 1991
Rint0.087
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.122, 1.00
No. of reflections3335
No. of parameters221
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.66, 0.72

Computer programs: XSCANS (Siemens, 1994), XSCANS, SHELXTL/PC (Sheldrick, 1990), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL/PC.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···Br20.83712.45733.277 (6)166.42
N1—H1A···O2W0.85961.94982.804 (6)172.01
N1—H1B···Br1i0.87 (5)2.60 (5)3.358 (5)146 (5)
O1—H2···Br2ii0.81 (7)2.48 (7)3.279 (5)173 (6)
O1W—H1WB···Br2iii0.79932.51613.294 (5)164.80
N2—H2A···O1iv0.98 (6)2.18 (7)2.886 (7)127 (5)
N2—H2A···O2Wiv0.98 (6)2.22 (6)2.918 (7)127 (5)
N2—H2B···Br10.82 (7)2.51 (7)3.307 (5)164 (6)
O2W—H2WA···O1Wi0.84 (7)1.93 (7)2.756 (7)171 (7)
O2W—H2WB···Br10.80 (6)2.54 (7)3.332 (5)173 (6)
Symmetry codes: (i) x, y+1, z; (ii) x+1/2, y+1/2, z+3/2; (iii) x+1/2, y1/2, z+3/2; (iv) x+1, y+1, z+1.
 

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