Cyclic Imide and Open-Chain Amide Carboxylic Acid Derivatives from the Facile Reaction of cis-Cyclohexane-1,2-dicarboxylic Anhydride with Three Substituted Anilines

The structures of the compounds from the reaction of cis-cyclohexane-1,2-dicarboxylic anhydride with 4-chloroaniline [rac-N-(4-chlorophenyl)-2-carboxycycloclohexane-1-carboxamide] (1), 4-bromoaniline [2-(4-bromophenyl)-perhydroisoindolyl-1,3-dione] (2) and 3-hydroxy-4-carboxyaniline (5-aminosalicylic acid) [2-(3-hydroxy-4-carboxyphenyl)-perhydroisoindolyl-1,3-dione] (3) have been determined at 200 K. Crystals of the open-chain amide carboxylic acid 1 are orthorhombic, space group Pbcn, with unit cell dimensions a = 20.1753(10), b = 8.6267(4), c = 15.9940(9) Å, and Z = 8. Compounds 2 and 3 are cyclic imides, with 1 monoclinic having space group P21 and cell dimensions a = 11.5321(3), b = 6.7095(2), c = 17.2040(5) Å, β = 102.527(3)o. Compound 3 is orthorhombic with cell dimensions a = 6.4642(3), b = 12.8196(5), c = 16.4197(7) Å. Molecules of 1 form hydrogen-bonded cyclic dimers which are extended into a two-dimensional layered structure through amide-group associations: 3 forms into one-dimensional zigzag chains through carboxylic acid…imide O-atom hydrogen bonds, while compound 2 is essentially unassociated. With both cyclic imides 2 and 3, disorder is found which involves the presence of partial enantiomeric replacement of the cis-cyclohexane-1,2-substituted ring systems.

Structure of 5'-O-acetyl-2',3'-O-isopropylideneuridine, C14H18N2O7

M r = 326.3, monoclinic, P21, a --= 6.510 (2), b=8.432 (2), c= 15.114 (2),a, /~= 101.42 (3) ° , Z = 2, V= 813.15 A 3, D x = 1-33 Mg m -3, F(000) = 172, 2(Cu Ka) = 1.5418/~,, g(Cu Ka) = 0.906 mm -~, final R = 6.4% for 1924 observed counter reflections. The conformation about the glycosidic bond is syn [torsion angle C(6)-N(1)-C(1')-O(4')=-103.9(3)°]. The sugar pucker is C(2')-exo,C(3')-endo (3Tz). The conformation about the C(4')-C(5') bond is gauche-trans. An uncommon intermolecular hydrogen bond involving the ribose-ring oxygen O(1') and the base-nitrogen N(3) stabilizes the crystal structure.

Polarized Ethylenes: Structure of 2-Benzoyl-3-dimethylamino-3-methylthlo-2-propenenitrile

C13H14N2OS, M r = 246, is monoclinic, P21/c, with a = 7.214(1), b = 8.935(5), c = 20.243 (6) A, fl =99.42 (2) °, V = 1304.83 ,~3, Z = 4, D m = 1.23, D x =1.25 Mg m -3, p(Mo Ka, 2 = 0.7107 A) = 0.232 mm -~,F(000) = 520. The structure was solved by direct methods and refined to an R value of 0.042 using 1127 intensity measurements. The C=C and C-N bond distances differ considerably from their normal values. An appreciable rotation [38.3(4) °] about the C=C bond is observed, the bond length being 1.414(5)A.This is due to the combination of push-pull and steric effects.

Push-pull ethylenes: the structures of 3-(2-imidazolidinylidene)-2,4-pentanedione (I), C8H12N2O2, and 3-(1,3-dimethyl-2-imidazolidinylidene)-2,4-pentanedione trihydrate (II), C10H16N2O2.3H2O

(I): Mr= 168, triclinic, P1, Z=2, a= 5.596 (2), b = 6.938 (3), c = 10.852 (4) A, ~t= 75.64 (3), fl= 93.44 (3), ),= 95.47 (3) °, V= 406.0A 3, Din= 1.35 (by flotation using carbon tetrachloride and n-hexane), D x= 1.374 Mg m -3, g(Mo Kct, 2 = 0.7107 A) = 1.08 cm -l, _F(000) = 180, T= 293 K. (II): Mr= 250, triclinic, P1, Z= 2, a = 7.731(2), b=8.580(2), c=11.033(3)A, a= 97-66 (2), fl= 98.86 (2), y= 101.78 (2) °, V= 697.5 A 3, D m = 1.18 (by flotation using KI solution), Dx= 1.190Mgm -3, g(MoKa, 2=0.7107A)= 1.02 cm -1, F(000) = 272, T= 293 K. Both structures were solved by direct methods and refined to R = 4.4% for 901 reflexions for (I) and 5.7% for 2001 reflexions for (II). The C=C bond distances are 1.451 (3) A in (I) and 1.468 (3)A in (II), quite significantly longer than the C=C bond in ethylene [1.336 (2).~; Bartell, Roth, Hollowell, Kuchitsu & Young (1965). J. Chem. Phys. 42, 2683-2686]. The twist angle about the C=C bond in (II) is 72.9 (5) ° but molecule (I) is essentially planar, the twist angle being only 4.9 (5) ° .

Hydrothermal synthesis of polycrystalline carbonates

Polycrystals of orthorhobic carbonates RCO3 (R = Sr, Ba and Pb) were synthesised for the first time using formic acid as mineraliser. The unit cell parameters of this synthetic pure carbonates are: BaCO3:a=5.309, B=8.889, C=6.401; srCO3:a=5.108, B=8.420, C=6.040; PbCO3: A=5.176, B=8.511, C=6.137.

Studies in Nonlinear Optical Materials: Structure of Methyl 2-(4-Ethyl-5-methyl- 2-thioxo-2,3-dihydro-l,3-thiazol- 3-yl) propionate

CIoH15NO282, Mr=245"0, orthorhombic, P21212 ~, a = 6.639 (2), b = 8.205 (2), c = 22.528(6)A, V= I227.2(6)A 3, z=4, Dm= 1.315, Dx= 1.326gem -3, MoKa, 2=0.7107A, 12= 3.63 cm -1, F(000) = 520, T= 293 K, R = 0.037 for 1115 significant reflections. The second-harmonicgeneration (SHG) efficiency of this compound is only 1/10th of the urea standard. The observed low second-order nonlinear response may be attributed to the unfavourable packing of the molecules in the crystal lattice.

Thermally Induced Acyl Migration in Salicylamides. 1. Structures of the Reactants, O-Acetylsalicylamide and O-Benzoylsalicylamide

O-Acetylsalicylamide (Ia), C9H9NO3, M r =179.18, monoclinic, P2Jc, a=8.155(5), b=8.571 (2), c= 13.092 (3)A, fl=99.54 (5) ° , V= 902.4(6)A 3, Z=4, Dm=l.31, Dx=l.319gcm -3, 2(Mo Ka) = 0.71069 A,/~ = 1.08 cm -1, F(000) = 376, T = 295 K, R = 0.076 for 1604 reflections. O-Benzoylsalicylamide (Ib), C14HtlNO 3, M,=241.2, monoclinic, P2t/e, a=9.423(1), b=5.116(1), e= 26.424 (2) A, fl= 103.97 (1)% V= 1236.2 (3)/~3, Z= 4, D~ = 1.28, D x = 1.296 gcm -3, ,;L(Cu Ks) = 1.5418 A, p = 7.71 cm-', F(000) = 504, T= 295 K, R =0.050 for 2115 reflections. The dihedral angles between the amide group and the benzene ring are 39.9 ° (Ia) and 37.9 ° (Ib), whereas between the acyl group and the benzene ring they are 78.1 ° (Ia) and 93.4 ° (Ib). The differences in the packing of the two structures are brought out in terms of the observed hydrogen-bonding patterns. Based on the crystallographic results, an intramolecular mechanism for the migration of the acyl group from the O to the N position is suggested in both compounds.

L-Arginine L-aspartate

C6HxsN40 +.C4H6NO~-, monoclinic, P2,,a = 5.511 (3), b = 8.438 (4), c = 15.265 (9) A, fl = 97.9 (I) °, D,, -- 1.467 (8) (flotation), D c = 1.452 Mg m -a, Z = 2. The structure has been refined to a final R value of 0.044 for 1226 independent counter-measured reflections. The conformation of the arginine molecule is different from those previously observed, whereas the conformation of the aspartate ion is similar to that found in L-aspartic acid, DL-aspartic acid and L-lysine L-aspartate. The unlike molecules aggregate into separate alternating layers and the a-amino and acarboxylate groups in the arginine layer are periodically brought into close proximity in a 'headto-tail' arrangement. There exist a specific ion-pair interaction involving electrostatic attraction and two nearly parallel N-H...O hydrogen bonds between the guanidyl group and the a-carboxylate group of the aspartate ion.

Ternary metal complexes of anionic and neutral pyridoxine (vitamin B6) with 2,2'-bipyridine. Syntheses and x-ray structures of (pyridoxinato)bis(2,2'-bipyridyl)cobalt(III) perchlorate and chloro(2,2'-bipyridyl)(pyridoxine)copper(II) perchlorate hydrate

Ternary metal complexes involving vitamin B6 with formulas [CO",(PN-H)](anCdI [OC)'(bpy)(PN)Cl]C10(.bpHy 0 = 2,2'-bipyridine, PN = neutral pyridoxine, PN-H = anionic pyridoxine) have been prepared for the first time and characterized by means of magnetic and spectroscopic measurements. The crystal structures of the compounds have also been determined. [CO(PN-H)](CcryIsOta,l)lize s in the space group P2,/c with a = 18.900 (3) A, b = 8.764 (1) A, c = 20.041 (2) A,p = 116.05 (l)', and Z = 4 and [Cu(bpy)(PN)C1]C104-H20in the space group Pi with a = 12.136 (5) A, b = 13.283 (4) A,c = 7.195 (2) A, a = 96.91 (Z)', 0 = 91.25 (3)', y = 71.63 (3)', and Z = 2. The structures were solved by the heavy-atom method and refined by least-squares techniques to R values of 0.080 and 0.042 for 3401 and 2094 independent reflections, respectively. Both structures consist of monomeric units. The geometry around Co(II1) is octahedral and around Cu(I1) is distorted square pyramidal. In [CO(PN-H)]t(wCo IoxOy~ge)n~s ,fro m phenolic and 4-(hydroxymethyl) groups of PN-H and two nitrogens from each of two bpy's form the coordination sphere. In [Cu(bpy)(PN)C1]C104.H20o ne PN and one bpy, with the same donor sites, act as bidentate chelates in the basal plane, with a chloride ion occupying the apical position. In both structures PN and PN-H exist in the tautomeric form wherein pyridine N is protonated and phenolic 0 is deprotonated. However, a novel feature of the cobalt compound is that PN-H is anionic due to the deprotonation of the 4-(hydroxymethyl) group. The packing in both structures is governed by hydrogen bonds, and in the copper compound partial stacking of bpy's at a distance of -3.55 also adds to the stability of the system. Infrared, NMR, and ligand field spectroscopic results and magnetic measurements are interpreted in light of the structures.

Polarized ethylenes: structures of (1,3-dimethyl-2-imidazolidinylidene)malononitrile and (1,3-dimethyl-2-perhydropyrimidinylidene)malononitrile

Crystal structures of the title compounds, (I) and (II), have been determined by three-dimensional diffraction methods. Crystals of CsHIoN 4 (I) are monoclinic, space group P21/a with Z = 4, Mr= 162, a = 7.965 (1), b = 16.232 (2), c = 7.343 (1) A, fl = 113.54 (1) °, V = 890.7 A 3, D,n = 1.218, D x = 1.208 gcm -3, g(Cu Ka, 2 = 1.5418/~) = 6.47 em -1, F(000) = 344. The crystals of C9H12N4 (II) are orthorhombic, space group P21en, with Z = 4, Mr = 176, a = 7.983 (3), b = 8.075 (2), c = 14.652 (3) ./k, V = 944.43/~3, Dm= 1.219, D x = 1.237 g cm -3, #(Mo Ka, ). = 0.7107 ,/k) = 0.868 cm -1, F(000) = 376. Both structures were solved by direct methods and refined to R = 5.8% for (I) and 5.3 % for (II). The C-C double-bond distances are 1.407 (3) in (I) and 1.429 (6)/~ in (II), appreciably longer than normal. The steric and push-pull effects result in rotation about the C=C bond, the rotation angles being 20.2 (3) in (I) and 31.5 (6) o in (II).

X-Ray Studies On Crystalline Complexes Involving Amino-Acids And Peptides .11. Peptide Aggregation And Water-Structure In The Crystals Of A Hydrated 1-1 Complex Between L-Histidyl-L-Serine And Glycyl-L-Glutamic Acid

The hexahydrate of a 1:1 complex between L-histidyl-L-serine and glycyl-L-glutamic acid crystallizes in space group P1 with a = 4.706(1), b= 8.578(2), c= 16.521(3) ÅA; α= 85.9(1), β= 89.7(1)°, = 77.4(1). The crystal structure, solved by direct methods, has been refined to an R value of 0.046 for 2150 observed reflections. The two peptide molecules in the structure have somewhat extended conformations. The unlike molecules aggregate into separate alternating layers. Each layer is stabilized by hydrogen bonded head-to-tail sequences as well as sequences of hydrogen bonds involving peptide groups. The arrangement of molecules in each layer is similar to one of the plausible idealized arrangements of L-alanyl-L-alanine worked out from simple geometrical considerations. Adjacent layers in the structure are held together by interactions involving side chains as well as water molecules. The water structure observed in the complex provides a good model, at atomic resolution, for that in protein crystals. An interesting feature of the crystal structure is the existence of two water channels in the interfaces between adjacent peptide layers.

Studies on crystalline complexes involving amino acids. V. The structure of L-serine-L-ascorbic acid

L-Serine-L-ascorbic acid, C3HTNOa. C6HsO6, a 1:1 complex between the amino acid serine and the vitamin ascorbic acid, crystallizes in the orthorhombic space group P2~2~2~ with four formula units in a cell of dimensions a = 5.335(3), b = 8.769(2), c = 25.782 (5) A. The structure was solved by direct methods and refined by full-matrix least squares to an R of 0.036 for 951 observed reflections. Both molecules are neutral in the structure. The conformation of the serine molecule is different from that observed in the crystal structures of L-serine, DL-serine and L-serine monohydrate. The enediol group in the ascorbic acid molecule is planar, whereas significant departures from planarity are observed in the lactone group. The conformation of this molecule is similar to that observed in arginine ascorbate. The unlike molecules aggregate into separate columns in the crystal structure. The columns are held together by hydrogen bonds. Among these, a pair of hydrogen bonds between the enediol group of ascorbic acid and the carboxylate group of serine provides a possible model for a specific interaction between ascorbic acid and a carboxylate ion.

The structure of the monobarium salt of glucose 6-phosphate heptahydrate

C6H11o9P2-.Ba2+.7H2o, M, = 521.5, is monoclinic, space group P21, a = 11.881 (4), b = 8.616 (5), c = 8.350 (4) A,B = 102.95 (3)0, Z = 2, U = 833.0 A 3, d m = 2.09, d c = 2.08 Mg m -3, F(000) = 516. Mo Ka (u = 0.034 mm -1) intensity data. R is 0.068 for 1603 reflections. Of the two endocyclic C-O bonds in the glucose ring, C(5)-O(5) [1.463 (23)] is longer than C(1)-O(5) [1.395 (23)A]. The pyranose sugar ring takes a 4C1 chair conformation. The Cremer-Pople puckering parameters are, 0 = 6.69 o, Q = 0.619 A and 0 = 263.7o. The conformation about the exocyclic C(5)-C(6) bond is gauche-gauche, in contrast to gauche-trans observed in the structure of glucose 1-phosphate. The phosphate ester bond, P-O(6), is 1.61 (1)A. It is similar in length to the 'high-energy' P~O bond in phosphoenolpyruvate. The Ba 2÷ ion is surrounded by nine O atoms within a distance of 2.95 A, of which seven are from water molecules. There is an intramolecular hydrogen bond between the sugar hydroxyl 0(4) and phosphate oxygen O(12).

Polarized Ethylenes: Structures of (l,3-Dimethyl-2-imidazolidinylidene)malononitrile and (l,3-Dimethyl-2-perhydropyrimidinylidene)malononitrile

Crystal structures of the title compounds, (I) and (II), have been determined by three-dimensional diffraction methods. Crystals of CsHIoN 4 (I) are monoclinic, space group P21/a with Z = 4, Mr= 162, a = 7.965 (1), b = 16.232 (2), c = 7.343 (1) A, fl = 113.54 (1) °, V = 890.7 A 3, D,n = 1.218, D x = 1.208 gcm -3, g(Cu Ka, 2 = 1.5418/~) = 6.47 em -1, F(000) = 344. The crystals of C9H12N4 (II) are orthorhombic, space group P21en, with Z = 4, Mr = 176, a = 7.983 (3), b = 8.075 (2), c = 14.652 (3) ./k, V = 44.43/~3, Dm= 1.219, D x = 1.237 g cm -3, #(Mo Ka, ). = 0.7107 ,/k) = 0.868 cm -1, F(000) = 376. Both structures were solved by direct methods and refined to R = 5.8% for (I) and 5.3 % for (II). The C-C double-bond distances are 1.407 (3) in (I) and 1.429 (6)/~ in (II), appreciably longer than normal. The steric and push-pull effects result in rotation about the C=C bond, the rotation angles being 20.2 (3) in (I) and 31.5 (6) o in (II).

Structural Studies of Analgesics and Their Interactions. VIII.* Rotational Isomerism and Disorder in the Crystal Structure of Meelofenamie Acid

Meclofenamic acid, C I4HIICI2NO2, probably the most potent among analgesic fenamates, crystallizes in the triclinic space group P1, with a = 8.569 (5), b = 8.954(8), c -- 9.371 (4) A, ct = 103.0 (2), fl -- 103.5 (2), y = 92.4 (2) ° , Z = 2, D m = 1.43 (4), D c = 1.41 Mg m -3. The structure was solved by direct methods and refined to R = 0.135 for 1062 observed reflections. The anthranilic acid moiety in the molecule is nearly planar and is nearly perpendicular to the 2,6-dichloro-3-methylphenyl group. The molecules, which exist as hydrogen-bonded dimers, have an internal hydrogen bond involving the imino and the carboxyl groups. The methyl group is disordered and occupies two positions with unequal occupancies. The disorder can be satisfactorily explained in terms of the rotational isomerism of the 2,6-dichloro-3-methylphenyl group about the bond which connects it to the anthranilic acid moiety and the observed occupancies on the basis of packing considerations.