Urea adducts

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Urea can crystallise with other compounds. These can be called urea adducts or if a solvent is involved, a urea solvate, and the process is called urea extraction crystallization. Urea can also be a neutral ligand if it is coordinated to a central metal atom. Urea can form hydrogen bonds to other oxygen and nitrogen atoms in the substance it crystallises with. This stiffens the solid and raises the melting point. [1] T

List

nameformularatio

urea: solute

crystal systemspace groupunit cellvolumedensitycommentreference
hydrogen peroxide; urea (1:1)HOOH•CH4N2O1:1orthorhombicPncaa 6.732 b 4.8207 c 12.873 Z=4decomposes slowly at room temperature [2]
urea; acetic acid (1:2)2CH3COOH•CH4N2O1:2monoclinicP21/na 7.6549 b 10.1351 c 11.5219 β 99.570° Z=4881.471.358unstable in air [3]
oxalic acid; urea (1:1)C2H2O4•CH4N2O1:1monoclinicC2/ca 13.0625 b 6.6437 c 6.8478 β 92.474° [4]
oxalic acid; urea (1:2)C2H2O4•2CH4N2O2:1monoclinicP2/ca 5.058 b 12.400 c 6.964 β 98.13° [5]
Urea - N,N-dimethylformamide (3:1)3CH4N2O·C3H7NO3:1triclinicP1a = 7.525 b = 9.866 c = 10.821 α = 65.61° β = 79.43° γ = 70.76° Z=2689.71.219colourless @150K [6]
N,N-dimethylacetamide; urea (1:1)C4H9NO·CH4N2O1:1monoclinicC2/ca = 7.2770 b = 17.5394 c = 7.3789 β = 119.450° Z=4820.111.192colourless @120K [7]
Urea malonic acid1:1monoclinicP2/ca 13.091 b 5.455 c 9.933 β 104.39° [8]
Maleic acid; urea (1:1)1:1monoclinicCca 5.144 b 9.999 c 14.80 β 95.1° [9]
Succinic acid bis urea2:1monoclinicP21/ca 5.637 b 8.243 c 12.262 β 96.75° Z=2565.811.41 [10]
Maleic acid; urea (2:1)2:1monoclinicP21/na 5.661 b 11.754 c 19.173 β 91.56° [9]
Fumaric acid; urea (1:2)1:2monoclinicP21/ca 5.540 b 8.227 c 12.426 β 97.22° [11]
D-Tartaric1:1orthorhombicP212121a 17.229 b 9.824 c 5.056 Z=41.63transparent 255 to 1370 nm; SHG 3×KDP [12]
DL-Tartaric1:1monoclinicP21a 7.6973 b 23.3310 c 4.8727 β 100.82°NLO; transparent from 240 to 1950 nm [13]
Gluatric acid bis urea2:1monoclinicC2/ca 11.954 b 10.932 c 9.078 β 97.86° Z=4 [14]
Itaconic acid 1:1monoclinicP21/ca 12.71 b 5.2695 c 13.833β 104.78° [15]
2-bromotetradecane ureahexagonalP6122a=8.2582 c=10.9937298K [16]
2-bromotetradecane ureaorthorhombicC2221207K [16]
2-bromotetradecane ureamonoclinicP21a 16.338(1)Å b 10.9665(8)Å c 16.338(1)Å, α 90° β 60.00° [16]
4-amino benzoic acid; urea (2:1)(C7H7NO2)2(CH4N2O)1:2orthorhombicPnaba=7.4159 b=11.870 c=18.750 [17]
salicylic acid; urea (1:1)1:1monoclinicC2/ca=22.206 b=5.108 c=17.177 β=106.18 Z=8°1.407 [18]
5-nitro salicylic acid; urea (2:1)(C7H5NO5)2(CH4N2O)1:2triclinicP1a=6.9889 b=12.1968 c=12.3622 α=60.923° β=81.169° γ=76.938° [17]
3,5-dinitro salicylic acid; urea (1:1)(C7H4N2O7)(CH4N2O)1:1monoclinicP21/ca=4.942 b=22.337 c=10.389 β=100.92° [17]
o-phthalic acid; urea (1:1)1:1triclinicP1a=7.422 b=7.662 c=10.088 α=85.95° β=82.01° γ=65.14° [17]
urea : 1,4-dioxane (1 : 1)C4H8O2•C3H6O1:1monoclinicP2/ca=6.7949 b=4.5234 c=12.2711 β=95.701° Z=2 [1]
urea : morpholine (1 : 1)C4H8ON•C3H6O1:1orthorhombicPbcma=4.5847 b=19.131 c=8.9047 Z=4 [1]
3,5-dimethylpyridine bis(urea)(CH3)2C5H3N•2C3H6O2:1orthorhombicAbm2a=21.737 b=7.2102 c=15.590 Z=82443.41.236at 173K [19]
3,5-dimethylpyridine bis(urea)(CH3)2C5H3N•2C3H6O2:1monoclinicCca=8.5829 b=21.4843 c=7.2050 β=114.405° Z=41209.871.248at 100K [19]
2,6-dimethylpyridine urea(CH3)2C5H3N•C3H6O1:1triclinicP1a=7.4126 b=7.6720 c=8.1731 α=88.391° β=83.564° γ=80.059° Z=2454.921.221at 100K [19]
urea 2,6-dimethylpyridine(CH3)2C5H3N•C3H6O1:1monoclinicC2/ca=1.426 b=11.1168 c=7.4318 β=101.23° Z=4925.91.200at 200K [19]
2,6-dimethylpyridine bis(urea)(CH3)2C5H3N•2C3H6O2:1orthorhombicPnmaa=8.0772 b=7.2986 c=20.4169 Z=41203.641.254at 100K [19]
2,6-dimethylpyridine bis(urea)(CH3)2C5H3N•2C3H6O2:1monoclinicC2/ca=11.160 b=11.5421 c=10.910 β=116.12° [17]
2-picoline; urea (1:1)C6H7N·CH4N2O1:1orthorhombicPbcaa = 7.471 b = 14.916 c = 15.338 Z = 81709.2 [20]
Urea pyrazine-2,3-dicarboxylic acid1:1monoclinicP21/na=7.725 b=10.2530 c=12.612 β=97.997° [17]
bipyridine ureatriclinicP1a=7.200 b=8.297 c=9.835 α=75.849° β=70.744° γ =73.045° [21]
bipyridine ureatriclinicP1a=7.2862 b=8.3747 c=9.8647 α=76.061° β=72.789° γ=74.121° [21]
1,10-Phenanthroline urea1:1monoclinicC2/ca=14.342 b=12.002 c=7.3724 β 116.743° [21]
2,9-Dimethyl-1,10-phenanthroline urea1:1orthorhombicCmcma=11.370 b=17.351 c=7.3593 [21]
sodium chloride; urea; water (1:1:1)NaCl·CH4N2O·H2O1:1triclinica = 6.44 Å, b = 5.245Å, c = 17.312 Å, and a=90°, β=90.15°, γ=90°588.76SHG 1.53 × KDP, birefringence 0.084@1064 nm UV edge 209 nm [22] [23]
Bis(2-3-isopropyl-7-oxocyclohepta-1,3,5-trien-1-olato)bis[(3-isopropyl-7-oxocyclohepta-1,3,5-trien-1-olato)copper(II)]-urea-acetone (1/6/2)[Cu2(C10H11O2)4]·6CH4N2O·2C3H6O5:1monoclinicP21/ca 17.0125 b 11.0470 c 17.2731 β 110.385° Z=23042.951.371green [24]
aqua(N-salicylidene-rac-alaninato- O,N,O')copper(II)-urea (1/1)1:1triclinicP1a = 7.637, b = 8.509 c = 10.716 α = 93.10° β = 97.97° γ= 106.37° Z= 2,658.5blue [25]
Aqua[9-(1,8-diazafluoren-9-ylidene)amino-1,8-diazafluorenato]hydroxo(urea)zinc(II) urea solvate[Zn(C22H12N5)(OH)(CH4N2O)(H2O)]•C4N2O1:1monoclinicP21/ca 7.8637 b 16.0133 c 17.9513 β 101.358° Z=42216.21.687purple [26]
Pentakis(carbamide)dioxoneptunium(V) nitrate[NpO2{OC(NH2)2}5](NO3)monoclinicP21a = 11.142, b = 7.6379 c = 11.143 β = 108.9° Z = 2897.1 [27]
Bis[(isothiocyanato)tetraureadioxoneptunium(V)] urea{NpO2(NCS)[OC(NH2)2]4}2 · OC(NH2)2tetragonalP43212a=7.851 c=56.84 Z=435042.265light green [28]

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References

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  11. ↑ Videnova-Adrabińska, V. (1996-12-01). "Symmetry constraints, molecular recognition and crystal engineering. Comparative structural studies of urea–butanedioic and urea– E -butanedioic acid (2:1) cocrystals". Acta Crystallographica Section B Structural Science. 52 (6): 1048–1056. Bibcode:1996AcCrB..52.1048V. doi:10.1107/S0108768196005216. ISSN   0108-7681.
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  14. ↑ Videnova-Adrabińska, Veneta; Etter, Margaret C. (December 1995). "Urea-glutaric acid (2:1) structural aggregates as building blocks for crystal engineering". Journal of Chemical Crystallography. 25 (12): 823–829. Bibcode:1995JCCry..25..823V. doi:10.1007/BF01671077. ISSN   1074-1542. S2CID   94295605.
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  20. ↑ Ashurov, Jamshid; Ibragimov, Bakhtiyar; Talipov, Samat (2012-02-15). "2-Methylpyridine–urea (1/1)". Acta Crystallographica Section E: Structure Reports Online. 68 (2): o504. Bibcode:2012AcCrE..68O.504A. doi:10.1107/S1600536812002164. ISSN   1600-5368. PMC   3275249 . PMID   22347105.
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  22. ↑ Huang, Tingting; Wang, Ying; Yang, Daqing; Zhang, Bingbing (2023-08-21). "NaCl·CH 4 N 2 O·H 2 O: An Organic–Inorganic Hybrid Ultraviolet Nonlinear Optical Crystal with Optimized Comprehensive Properties". Inorganic Chemistry. 62 (33): 13626–13631. doi:10.1021/acs.inorgchem.3c02025. ISSN   0020-1669. PMID   37556794. S2CID   260773568.
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  24. ↑ Ho, Douglas M. (2010-10-15). "A urea adduct of bis(hinokitiolato)copper(II)". Acta Crystallographica Section C Crystal Structure Communications. 66 (10): m294–m299. Bibcode:2010AcCrC..66M.294H. doi:10.1107/S0108270110035602. ISSN   0108-2701. PMID   20921607.
  25. ↑ Warda, S. A. (1999-03-01). "Crystal structure of dimeric aqua(N-salicylidene-rac-alaninato- O,N,O')copper(II)-urea (1/1), C11H15CuN3O5". Zeitschrift für Kristallographie - New Crystal Structures. 214 (1): 77–78. doi: 10.1515/ncrs-1999-0141 . ISSN   2197-4578. S2CID   96765755.
  26. ↑ Komen, R. P.; Miskelly, G. M.; Oliver, A.; Rickard, C. E. F. (1999-08-15). "Aqua[9-(1,8-diazafluoren-9-ylidene)amino-1,8-diazafluorenato]hydroxo(urea)zinc(II) urea solvate". Acta Crystallographica Section C Crystal Structure Communications. 55 (8): 1213–1215. Bibcode:1999AcCrC..55.1213K. doi:10.1107/S0108270199005995. ISSN   0108-2701.
  27. ↑ Budantseva, N. A.; Andreev, G. B.; Krot, N. N.; Antipin, M. Yu. (2003). "[No title found]". Russian Journal of Coordination Chemistry. 29 (3): 222–226. doi:10.1023/A:1022892000172. S2CID   91233429.
  28. ↑ Andreev, G. B. (2000). "[No title found]". Doklady Chemistry. 375 (4/6): 285–288. doi:10.1023/A:1026699418221. S2CID   92340176.
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