organic compounds
1,4,8,11-Tetrakis(carboxymethyl)-5,5,7,12,12,14-hexamethyl-4,11-diaza-1,8-diazoniacyclotetradecane dichloride dihydrate
aKey Laboratory of Tropical Biological Resources of the Ministry of Education, Hainan University, Haikou 570228, People's Republic of China, and Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, School of Ocean, Hainan University, Haikou 570228, People's Republic of China, and bDepartment of Pharmaceutical Engineering, School of Ocean, Hainan University, Haikou 570228, People's Republic of China
*Correspondence e-mail: wangsf777@gmail.com
The title compound, C24H46N4O82+·2Cl−·2H2O, was synthesized by the hydrolysis of tetraethyl 2,2′,2′′,2′′′-(5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrayl) tetraacetate in hydrochloric acid solution. The of the title compound consists of a 14-membered C10N4 centrosymmetric cationic macrocycle which interacts with the chloride ions and water molecules of crystallization to give a three-dimensional hydrogen-bonded network.
Related literature
For related literature, see: Marinelli et al. (2002); Wang (2001); Xu et al. (1988).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.
Supporting information
10.1107/S1600536808010532/wn2251sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808010532/wn2251Isup2.hkl
Tetraethyl 2,2',2'',2'''-(5,5,7,12,12,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrayl)tetraacetate (0.625 g, 1 mmol) was dissolved in 200 ml of hydrochloric acid solution (v:v, 1:1) and allowed to stand in air at room temperature over a period of three weeks. Colourless block crystals suitable for X-ray
were formed at the bottom of the vessel (yield 87%).The water hydrogen atoms were refined freely, resulting in O—H bond lengths of 0.76 (3) and 0.88 (5) Å. Other H atoms were positioned geometrically, with N—H = 0.91 Å, O—H = 0.82 Å, C—H = 0.96 Å for methyl, 0.97 Å for methylene and 0.98 Å for methine. Uiso(H) = xUeq(carrier atom), where x = 1.5 for O and methyl, x = 1.2 for all other carrier atoms. The value of Rint (0.14) is high because of the quality of the diffraction data.
Data collection: SMART (Bruker, 2001); cell
SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local programs.C24H46N4O82+·2Cl−·2H2O | F(000) = 672 |
Mr = 625.58 | Dx = 1.378 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 17651 reflections |
a = 9.977 (5) Å | θ = 2.4–24.9° |
b = 13.475 (7) Å | µ = 0.27 mm−1 |
c = 11.572 (6) Å | T = 293 K |
β = 104.220 (9)° | BLOCK, colorless |
V = 1508.1 (13) Å3 | 0.10 × 0.10 × 0.08 mm |
Z = 2 |
Bruker SMART CCD area-detector diffractometer | 2036 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.143 |
Graphite monochromator | θmax = 26.0°, θmin = 2.4° |
ϕ and ω scans | h = −12→12 |
15242 measured reflections | k = −16→16 |
2946 independent reflections | l = −14→14 |
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)] = 0.056 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.141 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.99 | w = 1/[σ2(Fo2) + (0.0715P)2] where P = (Fo2 + 2Fc2)/3 |
2946 reflections | (Δ/σ)max = 0.032 |
194 parameters | Δρmax = 0.63 e Å−3 |
0 restraints | Δρmin = −0.37 e Å−3 |
C24H46N4O82+·2Cl−·2H2O | V = 1508.1 (13) Å3 |
Mr = 625.58 | Z = 2 |
Monoclinic, P21/n | Mo Kα radiation |
a = 9.977 (5) Å | µ = 0.27 mm−1 |
b = 13.475 (7) Å | T = 293 K |
c = 11.572 (6) Å | 0.10 × 0.10 × 0.08 mm |
β = 104.220 (9)° |
Bruker SMART CCD area-detector diffractometer | 2036 reflections with I > 2σ(I) |
15242 measured reflections | Rint = 0.143 |
2946 independent reflections |
R[F2 > 2σ(F2)] = 0.056 | 0 restraints |
wR(F2) = 0.141 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.99 | Δρmax = 0.63 e Å−3 |
2946 reflections | Δρmin = −0.37 e Å−3 |
194 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 | ||
C1 | 0.5351 (3) | 0.98193 (17) | −0.1532 (2) | 0.0292 (6) | |
H1A | 0.4667 | 0.9400 | −0.1306 | 0.035* | |
H1B | 0.5360 | 0.9664 | −0.2348 | 0.035* | |
C2 | 0.7189 (3) | 0.85672 (17) | −0.0818 (2) | 0.0335 (6) | |
H2 | 0.8150 | 0.8530 | −0.0349 | 0.040* | |
C3 | 0.6370 (3) | 0.78525 (17) | −0.0239 (2) | 0.0323 (6) | |
H3A | 0.6485 | 0.7189 | −0.0525 | 0.039* | |
H3B | 0.5398 | 0.8021 | −0.0511 | 0.039* | |
C4 | 0.6741 (3) | 0.78252 (17) | 0.1120 (2) | 0.0319 (6) | |
C5 | 0.5034 (2) | 0.90943 (16) | 0.1443 (2) | 0.0285 (6) | |
H5A | 0.4752 | 0.8726 | 0.2064 | 0.034* | |
H5B | 0.4516 | 0.8836 | 0.0682 | 0.034* | |
C6 | 0.7192 (4) | 0.8235 (2) | −0.2076 (3) | 0.0495 (8) | |
H6A | 0.6257 | 0.8156 | −0.2537 | 0.074* | |
H6B | 0.7673 | 0.7614 | −0.2041 | 0.074* | |
H6C | 0.7649 | 0.8726 | −0.2444 | 0.074* | |
C7 | 0.8226 (3) | 0.7482 (2) | 0.1616 (3) | 0.0422 (7) | |
H7A | 0.8371 | 0.6866 | 0.1248 | 0.063* | |
H7B | 0.8394 | 0.7391 | 0.2462 | 0.063* | |
H7C | 0.8850 | 0.7974 | 0.1450 | 0.063* | |
C8 | 0.5799 (3) | 0.70891 (19) | 0.1556 (3) | 0.0442 (7) | |
H8A | 0.6022 | 0.6425 | 0.1369 | 0.066* | |
H8B | 0.4851 | 0.7228 | 0.1169 | 0.066* | |
H8C | 0.5933 | 0.7154 | 0.2403 | 0.066* | |
C9 | 0.7378 (2) | 0.91341 (19) | 0.2780 (2) | 0.0328 (6) | |
H9A | 0.7422 | 0.8550 | 0.3278 | 0.039* | |
H9B | 0.6935 | 0.9660 | 0.3121 | 0.039* | |
C10 | 0.8828 (3) | 0.94509 (17) | 0.2765 (2) | 0.0303 (6) | |
C11 | 0.7806 (3) | 1.03008 (17) | −0.0922 (2) | 0.0338 (6) | |
H11A | 0.7562 | 1.0512 | −0.1749 | 0.041* | |
H11B | 0.8669 | 0.9937 | −0.0793 | 0.041* | |
C12 | 0.8052 (3) | 1.12186 (18) | −0.0142 (2) | 0.0319 (6) | |
Cl1 | 0.27157 (7) | 0.97170 (5) | 0.43440 (7) | 0.0480 (3) | |
N1 | 0.6734 (2) | 0.96203 (13) | −0.07355 (18) | 0.0270 (5) | |
H1N | 0.6660 | 0.9714 | 0.0025 | 0.032* | |
N2 | 0.6540 (2) | 0.89074 (14) | 0.15548 (17) | 0.0275 (5) | |
O1 | 0.74179 (19) | 1.14840 (14) | 0.05549 (17) | 0.0405 (5) | |
O2 | 0.9133 (2) | 1.17039 (15) | −0.0337 (2) | 0.0572 (6) | |
H2A | 0.9260 | 1.2212 | 0.0065 | 0.086* | |
O3 | 0.9143 (2) | 0.97572 (14) | 0.19069 (18) | 0.0449 (5) | |
O4 | 0.96439 (19) | 0.93712 (15) | 0.38441 (16) | 0.0434 (5) | |
H4 | 1.0409 | 0.9596 | 0.3849 | 0.065* | |
O1W | 0.5390 (3) | 0.84981 (16) | 0.4486 (2) | 0.0519 (6) | |
H2W | 0.594 (4) | 0.887 (2) | 0.479 (3) | 0.042 (10)* | |
H1W | 0.457 (5) | 0.877 (3) | 0.443 (4) | 0.092 (14)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0262 (13) | 0.0260 (12) | 0.0318 (13) | 0.0029 (10) | 0.0005 (11) | 0.0006 (10) |
C2 | 0.0304 (14) | 0.0251 (12) | 0.0417 (15) | 0.0084 (11) | 0.0026 (12) | −0.0014 (11) |
C3 | 0.0336 (14) | 0.0220 (12) | 0.0357 (14) | 0.0030 (11) | −0.0019 (11) | −0.0050 (10) |
C4 | 0.0332 (14) | 0.0217 (12) | 0.0356 (14) | 0.0055 (10) | −0.0012 (11) | −0.0029 (10) |
C5 | 0.0218 (12) | 0.0263 (12) | 0.0340 (14) | −0.0011 (10) | 0.0002 (11) | 0.0031 (10) |
C6 | 0.070 (2) | 0.0378 (15) | 0.0471 (18) | 0.0086 (15) | 0.0258 (16) | −0.0046 (13) |
C7 | 0.0435 (17) | 0.0368 (14) | 0.0398 (15) | 0.0101 (13) | −0.0021 (13) | −0.0001 (12) |
C8 | 0.0569 (19) | 0.0261 (13) | 0.0446 (16) | −0.0013 (13) | 0.0031 (14) | 0.0076 (12) |
C9 | 0.0271 (13) | 0.0387 (14) | 0.0279 (13) | 0.0018 (11) | −0.0022 (11) | −0.0041 (11) |
C10 | 0.0298 (14) | 0.0239 (12) | 0.0324 (14) | 0.0020 (10) | −0.0017 (11) | −0.0037 (10) |
C11 | 0.0292 (13) | 0.0320 (13) | 0.0405 (15) | −0.0007 (11) | 0.0094 (12) | −0.0045 (11) |
C12 | 0.0279 (14) | 0.0287 (13) | 0.0365 (14) | −0.0008 (11) | 0.0029 (12) | 0.0030 (11) |
Cl1 | 0.0331 (4) | 0.0426 (4) | 0.0634 (5) | −0.0038 (3) | 0.0023 (3) | 0.0034 (3) |
N1 | 0.0249 (11) | 0.0246 (10) | 0.0298 (11) | 0.0013 (8) | 0.0036 (9) | −0.0025 (8) |
N2 | 0.0248 (11) | 0.0229 (10) | 0.0298 (11) | 0.0027 (8) | −0.0025 (9) | −0.0029 (8) |
O1 | 0.0330 (10) | 0.0486 (11) | 0.0384 (11) | −0.0090 (9) | 0.0060 (9) | −0.0126 (9) |
O2 | 0.0537 (14) | 0.0430 (12) | 0.0839 (17) | −0.0206 (10) | 0.0339 (13) | −0.0177 (11) |
O3 | 0.0393 (12) | 0.0501 (12) | 0.0415 (12) | −0.0057 (9) | 0.0023 (9) | 0.0060 (9) |
O4 | 0.0286 (10) | 0.0547 (12) | 0.0392 (11) | −0.0042 (9) | −0.0065 (9) | −0.0003 (9) |
O1W | 0.0484 (15) | 0.0327 (11) | 0.0759 (17) | 0.0025 (11) | 0.0176 (13) | 0.0018 (11) |
C1—N1 | 1.483 (3) | C7—H7B | 0.9600 |
C1—C5i | 1.523 (3) | C7—H7C | 0.9600 |
C1—H1A | 0.9700 | C8—H8A | 0.9600 |
C1—H1B | 0.9700 | C8—H8B | 0.9600 |
C2—N1 | 1.500 (3) | C8—H8C | 0.9600 |
C2—C3 | 1.521 (4) | C9—N2 | 1.490 (3) |
C2—C6 | 1.524 (4) | C9—C10 | 1.513 (4) |
C2—H2 | 0.9800 | C9—H9A | 0.9700 |
C3—C4 | 1.525 (4) | C9—H9B | 0.9700 |
C3—H3A | 0.9700 | C10—O3 | 1.186 (3) |
C3—H3B | 0.9700 | C10—O4 | 1.317 (3) |
C4—C7 | 1.523 (4) | C11—N1 | 1.465 (3) |
C4—C8 | 1.535 (4) | C11—C12 | 1.515 (4) |
C4—N2 | 1.571 (3) | C11—H11A | 0.9700 |
C5—N2 | 1.497 (3) | C11—H11B | 0.9700 |
C5—C1i | 1.523 (3) | C12—O1 | 1.196 (3) |
C5—H5A | 0.9700 | C12—O2 | 1.327 (3) |
C5—H5B | 0.9700 | N1—H1N | 0.9100 |
C6—H6A | 0.9600 | O2—H2A | 0.8200 |
C6—H6B | 0.9600 | O4—H4 | 0.8200 |
C6—H6C | 0.9600 | O1W—H2W | 0.76 (3) |
C7—H7A | 0.9600 | O1W—H1W | 0.88 (5) |
N1—C1—C5i | 110.10 (18) | C4—C7—H7C | 109.5 |
N1—C1—H1A | 109.6 | H7A—C7—H7C | 109.5 |
C5i—C1—H1A | 109.6 | H7B—C7—H7C | 109.5 |
N1—C1—H1B | 109.6 | C4—C8—H8A | 109.5 |
C5i—C1—H1B | 109.6 | C4—C8—H8B | 109.5 |
H1A—C1—H1B | 108.2 | H8A—C8—H8B | 109.5 |
N1—C2—C3 | 111.5 (2) | C4—C8—H8C | 109.5 |
N1—C2—C6 | 114.2 (2) | H8A—C8—H8C | 109.5 |
C3—C2—C6 | 111.3 (2) | H8B—C8—H8C | 109.5 |
N1—C2—H2 | 106.4 | N2—C9—C10 | 111.2 (2) |
C3—C2—H2 | 106.4 | N2—C9—H9A | 109.4 |
C6—C2—H2 | 106.4 | C10—C9—H9A | 109.4 |
C2—C3—C4 | 116.7 (2) | N2—C9—H9B | 109.4 |
C2—C3—H3A | 108.1 | C10—C9—H9B | 109.4 |
C4—C3—H3A | 108.1 | H9A—C9—H9B | 108.0 |
C2—C3—H3B | 108.1 | O3—C10—O4 | 126.4 (3) |
C4—C3—H3B | 108.1 | O3—C10—C9 | 123.9 (2) |
H3A—C3—H3B | 107.3 | O4—C10—C9 | 109.6 (2) |
C7—C4—C3 | 111.3 (2) | N1—C11—C12 | 116.1 (2) |
C7—C4—C8 | 107.3 (2) | N1—C11—H11A | 108.3 |
C3—C4—C8 | 110.0 (2) | C12—C11—H11A | 108.3 |
C7—C4—N2 | 110.47 (19) | N1—C11—H11B | 108.3 |
C3—C4—N2 | 106.86 (18) | C12—C11—H11B | 108.3 |
C8—C4—N2 | 111.0 (2) | H11A—C11—H11B | 107.4 |
N2—C5—C1i | 114.86 (19) | O1—C12—O2 | 123.7 (2) |
N2—C5—H5A | 108.6 | O1—C12—C11 | 127.7 (2) |
C1i—C5—H5A | 108.6 | O2—C12—C11 | 108.7 (2) |
N2—C5—H5B | 108.6 | C11—N1—C1 | 113.39 (19) |
C1i—C5—H5B | 108.6 | C11—N1—C2 | 109.8 (2) |
H5A—C5—H5B | 107.5 | C1—N1—C2 | 112.43 (18) |
C2—C6—H6A | 109.5 | C11—N1—H1N | 106.9 |
C2—C6—H6B | 109.5 | C1—N1—H1N | 106.9 |
H6A—C6—H6B | 109.5 | C2—N1—H1N | 106.9 |
C2—C6—H6C | 109.5 | C9—N2—C5 | 111.37 (19) |
H6A—C6—H6C | 109.5 | C9—N2—C4 | 114.14 (17) |
H6B—C6—H6C | 109.5 | C5—N2—C4 | 109.45 (17) |
C4—C7—H7A | 109.5 | C12—O2—H2A | 109.5 |
C4—C7—H7B | 109.5 | C10—O4—H4 | 109.5 |
H7A—C7—H7B | 109.5 | H2W—O1W—H1W | 107 (3) |
N1—C2—C3—C4 | −75.6 (3) | C6—C2—N1—C11 | −71.7 (3) |
C6—C2—C3—C4 | 155.6 (2) | C3—C2—N1—C1 | −71.7 (3) |
C2—C3—C4—C7 | −62.6 (3) | C6—C2—N1—C1 | 55.5 (3) |
C2—C3—C4—C8 | 178.6 (2) | C10—C9—N2—C5 | −151.36 (19) |
C2—C3—C4—N2 | 58.1 (3) | C10—C9—N2—C4 | 84.1 (2) |
N2—C9—C10—O3 | 20.5 (3) | C1i—C5—N2—C9 | 67.6 (3) |
N2—C9—C10—O4 | −162.1 (2) | C1i—C5—N2—C4 | −165.3 (2) |
N1—C11—C12—O1 | −5.1 (4) | C7—C4—N2—C9 | −34.3 (3) |
N1—C11—C12—O2 | 174.1 (2) | C3—C4—N2—C9 | −155.5 (2) |
C12—C11—N1—C1 | 92.6 (3) | C8—C4—N2—C9 | 84.6 (2) |
C12—C11—N1—C2 | −140.7 (2) | C7—C4—N2—C5 | −159.9 (2) |
C5i—C1—N1—C11 | −52.7 (3) | C3—C4—N2—C5 | 78.9 (2) |
C5i—C1—N1—C2 | −178.0 (2) | C8—C4—N2—C5 | −41.0 (2) |
C3—C2—N1—C11 | 161.1 (2) |
Symmetry code: (i) −x+1, −y+2, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4···Cl1ii | 0.82 | 2.24 | 3.012 (3) | 158 |
O2—H2A···O1Wiii | 0.82 | 1.82 | 2.610 (3) | 162 |
O1W—H2W···Cl1iv | 0.76 (3) | 2.40 (3) | 3.152 (3) | 169 (3) |
Symmetry codes: (ii) x+1, y, z; (iii) −x+3/2, y+1/2, −z+1/2; (iv) −x+1, −y+2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C24H46N4O82+·2Cl−·2H2O |
Mr | 625.58 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 9.977 (5), 13.475 (7), 11.572 (6) |
β (°) | 104.220 (9) |
V (Å3) | 1508.1 (13) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.27 |
Crystal size (mm) | 0.10 × 0.10 × 0.08 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15242, 2946, 2036 |
Rint | 0.143 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.056, 0.141, 0.99 |
No. of reflections | 2946 |
No. of parameters | 194 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.63, −0.37 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL (Sheldrick, 2008) and local programs.
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4···Cl1i | 0.82 | 2.24 | 3.012 (3) | 158 |
O2—H2A···O1Wii | 0.82 | 1.82 | 2.610 (3) | 162 |
O1W—H2W···Cl1iii | 0.76 (3) | 2.40 (3) | 3.152 (3) | 169 (3) |
Symmetry codes: (i) x+1, y, z; (ii) −x+3/2, y+1/2, −z+1/2; (iii) −x+1, −y+2, −z+1. |
Acknowledgements
The work was supported by a Key Grant (No. 206118) from the Ministry of Education and the Natural Science Foundation of Hainan Province (No. 80619).
References
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N-functionalized macrocyclic acids are an important class of compounds for their utility as MRI contrast agents (Marinelli et al., 2002) and their strong chelating ability (Xu et al., 1988). For this reason, we have synthesized the title compound by the hydrolysis of tetraethyl 2,2',2'',2'''-(5,5,7,12,12,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrayl) tetraacetate (Wang et al., 2001) in hydrochloric acid solution.
The bond lengths and angles in the title compound are within normal ranges. The structural data confirm that the 14-membered macrocycle lies on a center of inversion and each N atom is linked to a carboxymethyl group. The macrocycle carries two positive charges arising from the protonation of N atoms. The net charge is balanced by two chloride ions. The cations and anions interact with each other and with the water molecules of crystallization to furnish a hydrogen-bonded network structure (Table 1). The structure of the title compound, showing 50% probability displacement ellipsoids is shown in Fig. 1 and a view of the hydrogen bonding in Fig. 2.