Mean Plane Of Ring Research Articles

(E)-13-(4-Amino-phen-yl)parthenolide.

The title compound, C21H25NO3 [systematic name: (3aS,9aR,10aR,10bS,E)-3-[(E)-4-(4-amino­benzyl­idene)-6,9a-dimethyl-3a,4,5,8,9,9a,10a,10b-octa­hydro­oxireno[2′,3′:9,10]cyclo­deca­[1,2-b]furan-2(3H)-one] was obtained from the reaction of parthenolide [synonym: 4,5-ep­oxy­germacra-1(10),11(13)-dieno-12,6-lactone] with 4-iodo­aniline under Heck reaction conditions. It was identified as the E-isomer (conformation about the exocyclic methyl­idene C=C bond; the conformation about the C=C bond in the ten-membered ring is also E). The mol­ecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings with a 4-amino­phenyl group as a substituent. The ten-membered ring displays an approximate chair–chair conformation, while the lactone ring has an envelope conformation with the C atom bonded to the ring O atom as the flap. The dihedral angle between the benzene ring of the 4-amino­phenyl moiety and the lactone ring mean plane is 23.50 (8)°. In the crystal, mol­ecules are linked via N—H⋯O hydrogen bonds, between the amine group and the lactone and epoxide ring O atoms, forming chains propagating along the b-axis direction. Adjacent chains are linked via C—H⋯O inter­actions, forming an undulating two-dimensional network lying parallel to the plane (001). The absolute structure of the mol­ecule in the crystal was confirmed by resonance scattering [Flack parameter = 0.03 (3)].

Methyl 2-[4-(tri-fluoro-meth-yl)phenyl-sulfan-yl]benzoate.

In the title compound, C15H13F3O2S, the dihedral angle between the benzene rings is 79.5 (1)°. The ester group is twisted by 7.6 (1)° from the mean plane of the adjacent benzene ring. Disorder was modeled over two sites for one F atom of the tri­fluoro­methyl group with an occupancy ratio of 0.54 (6):0.46 (6). In the crystal, mol­ecules are linked via weak C—H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to (101). The networks are linked via C—H⋯π inter­actions, leading to the formation of a three-dimensional supra­molecular structure.

Bis{4-[(1,3-benzodioxol-5-yl)meth-yl]piperazin-1-yl}methane.

In the title compound, C25H32N4O4, both piperazine rings adopt a chair conformation. One of dioxolane ring systems is essentially planar [dihedral angle = 0.9 (2)°] while the other adopts a slightly disordered envelope conformation, the mean plane of the dioxolane ring being twisted by 3.6 (2)° from that of the benzene ring. The dihedral angle between the benzene rings is 69.9 (5)°. No classical hydrogen bonds were observed.

2-(4-Fluorophenyl)-4-(thiophen-2-yl)-2,3-dihydro-1,5-benzothiazepine

In the title compound, C19H14FNS2, the seven-membered thia­zepine ring adopts a slightly distorted twist boat conformation. The dihedral angle between the benzene rings is 53.6 (1)°. The mean plane of the thia­zepine ring is twisted by 34.3 (7)° and 36.6 (7)° from the benezene rings. A C—H⋯F interaction generates stacking of molecules along the ab plane.

The six-membered-ring azomethineN-((E)-{5-[(E)-(pyridin-3-ylimino)methyl]thiophen-2-yl}methylidene)pyridin-3-amine

The title compound, C16H12N4S, forms a three-dimensional layered network structure via intermolecular hydrogen bonding and π-stacking. The azomethine molecule adopts the thermodynamically stable E regioisomer and the pyridine substituents are antiperiplanar. The mean planes of the pyridine rings and the azomethine group to which they are connected are twisted by 27.27 (5) and 33.60 (5)°. The electrochemical energy gap of 2.3 eV based on the HOMO-LUMO energy difference is in agreement with the spectroscopically derived value.

14a-Hydroxy-12-methyl-10-(4-methylphenyl)-8,9,9a,10,12,13,14,14a-octahydro-10a,14-methano-5H-indeno[2′,1′:4,5]azepino[3,4-b]pyrrolizine-5,15(7H,11H)-dione

In the title compound, C27H28N2O3, each of the pyrrolidine rings adopts a twisted conformation, as does the cyclo­pentane ring. The indane ring has an r.m.s deviation of 0.0693 Å. The dihedral angle between the mean plane of the pyrrolizine ring and indane system is 82.58 (1)°. The piperidine ring has the methyl substituent in an equatorial position and adopts a twisted chair conformation. The mol­ecular structure is stabilized by a weak intra­molecular O—H⋯N inter­action.

3-(1H-Imidazol-1-yl)propanaminium picrate

In the title salt [systematic name: 3-(1H-imidazol-1-yl)propanaminium 2,4,6-tri­nitro­phenolate], C6H12N3 +·C6H2N3O7 −, there are five independent cation–anion pairs (A, B, C, D, E) in the asymmetric unit. In the cation, the ammonium group is protonated with the amino­propyl group nearly at right angles to the mean plane of the imidazole ring showing C—N—C—C torsion angles ranging from 79.6 (2) to 99.79 (19)° in the five cations. The nitro groups in the anion are twisted from the benzene mean plane with maximum dihedral angles subtended by nitro substituents ortho to the phenolate O atom of 26.0 (2) and 37.3 (7) (A), 28.9 (5) and 35.3 (1) (B), 34.7 (7) and 36.9 (7) (C), 14.7 (4) and 36.9 (2) (D) and 33.1 (1) and 35.4 (3)° (E). In contrast, the nitro groups in the para positions lie much closer to the aromatic ring plane, subtending dihedral angles of 1.8 (3) (A), 3.5 (3) (B), 6.03 (C), 2.1 (3) (D) and 7.7 (1)° (E). Disorder is observed for one O atom of an ortho nitro group in anion D with an occupancy ratio of 0.53 (5):0.47 (5). In the crystal, N—H⋯O cation–anion and N—H⋯N cation–cation hydrogen bonds are observed, linking the ions into chains along [010]. In addition, weak C—H⋯O cation–anion inter­actions occur.

1,2:5,6-Di-O-isopropylidene-3-C-methyl-α-D-allofuranose

The title carbohydrate, C13H22O6, is a derivative of d-glycose, in which the furan­osidic and iso­propyl­idene rings are in twisted conformations. The mean plane of the furan­osidic ring makes a dihedral angle of 70.32 (18)° with the mean plane of the fused iso­propyl­idene ring. The methyl groups in the other iso­propyl­idene ring are disordered over two sets of sites, with an occupancy ratio of 0.74 (6):0.26 (6). In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds into chains with graph-set notation C(5) along [100]. Weak C—H⋯O interactions also occur.

(2,3,5,6-Tetrafluorophenolato)[5,10,15,20-tetrakis(4-methoxyphenyl)porphyrinato]iron(III) cyclohexane monosolvate

The title compound, [Fe(C6HF4O)(C48H36N4O4)]·C6H12, represents a five-coordinate iron(III) porphyrin complex in a square-pyramidal geometry with a tetra­fluoro­phenolate anion as the axial ligand. The FeIII atom is displaced by 0.364 (2) Å from the 24-atom mean plane of the porphyrinate ring towards the tetra­fluoro phenolate anion. The average Fe—N distance is 2.053 (2) Å and the Fe—O distance is 1.883 (2) Å. A porphyrin aryl H atom points in the general direction of the phenoxide ring. The mean plane separation between the 24-atom porphyrin planes of two adjacent porphyrin rings is ∼3.7 Å, and the lateral shift is ∼3.5 Å resu, ting in an Fe⋯Fe separation of 5.6167 (14) Å.

1′,1′′-Dimethyl-4′-(4-methylphenyl)dispiro[11H-indeno[1,2-b]quinoxaline-11,2′-pyrrolidine-3′,3′′-piperidin]-4′′-one

In the title compound, C31H30N4O, the central pyrrolidine ring adopts an envelope conformation with the methyl­ene C atom being the flap. The quinoxaline and indane rings are each planar, having r.m.s. deviations of 0.030 and 0.050 Å, respectively. The pyrrolidine ring mean plane forms dihedral angles of 88.25 (1) and 83.76 (1)° with the quinoxaline and indane rings, respectively. Intra­molecular C—H⋯O and C—H⋯N inter­actions are observed. In the crystal, C—H⋯π inter­actions lead to helical supra­molecular chains along the b-axis direction.

6-Ferrocenoyl-7-phenylspiro[hexahydropyrrolo[1,2-c][1,3]thiazole-5,11′-indeno[1,2-b]quinoxaline

In the title compound, [Fe(C5H5)(C32H24N3OS)], both the thia­zolidine ring and the pyrrolidine ring adopt an envelope conformation, with the S atom and the phenyl-bearing C atom, respectively, as the flaps. The thia­zolidine ring mean plane makes a dihedral angle of 59.08 (11)° with the pyrrolidine ring mean plane, which in turn makes a dihedral angle of 83.40 (10)° with the cyclo­pentane ring, indicating that the latter two rings are almost orthogonal to one another. In the crystal, a pair of C—H⋯O hydrogen bonds link the mol­ecules forming inversion dimers. The dimers are linked via π–π inter­actions [centroid–centroid distance = 3.7764 (10) Å] involving the quinoxaline moieties forming chains propagating along [1-10].

1′,1′′-Dimethyl-4′-phenyldispiro[11H-indeno[1,2-b]quinoxaline-11,2′-pyrrolidine-3′,3′′-piperidin]-4′′-one

In the title compound, C30H28N4O, the central pyrrolidine ring adopts an envelope conformation with the CH2 C atom as the flap. The quinoxaline and indene ring systems are planar, with r.m.s. deviations of 0.0165 and 0.0181 Å, respectively. The pyrrolidine ring mean plane forms dihedral angles of 88.84 (1) and 86.14 (1)° with the quinoxaline and indene ring systems, respectively. A weak intra­molecular C—H⋯N inter­action is observed. In the crystal, C—H⋯O inter­actions lead to helical supra­molecular chains along the b axis having a C(9) motif.

(4S*)-2-Methylamino-3-nitro-4-(4-nitrophenyl)-5,6,7,8-tetrahydro-4H-chromen-5-one

The title compound, C16H15N3O6, is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The six-membered carbocyclic ring adopts an envelope conformation with the central CH2 C atom as the flap. The amine N atom deviates from the mean plane of the pyran ring by 0.1365 (15) Å. The nitro­phenyl ring is almost orthogonal to the pyran ring and the mean plane of the six-membered carbocyclic ring, the dihedral angle between their mean planes being 88.30 (7) and 87.61 (8)°, respectively. The mol­ecular structure is stabilized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, forming infinite bands lying parallel to (-110) and composed of alternate R 2 2(24) and R 2 4(12) graph-set ring motifs. The crystal structure is further stabilized by C—H⋯π inter­actions, forming a three-dimensional structure.

1-Di-chloro-acetyl-t-3-isopropyl-r-2,c-6-di-phenyl-piperidin-4-one.

In the title compound, C22H23Cl2NO2, the piperidine ring adopts a twist-boat conformation. The phenyl rings substituted at the 2- and 6-positions of the piperidine ring subtend dihedral angles of 60.6 (2) and 84.2 (1)°, respectively, with the mean plane of the piperidine ring. In the crystal, mol­ecules are linked by C—H⋯O inter­actions into zigzag chains running along the c-axis direction.

Methyl 2-(2,2-dimethyl-3a,6a-di-hydro-furo[3,2-d][1,3]dioxol-5-yl)-4-oxo-4H-chromene-3-carboxyl-ate.

In the title mol­ecule, C18H16O7, the dioxolane ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap. The furan ring is almost coplanar with the pyran ring, with a dihedral angle of 1.04 (10)° between the planes, and it makes a dihedral angle of 67.97 (11)° with the mean plane of the dioxolane ring. The latter makes a dihedral angle of 67.15 (10)° with the pyran ring. The O atom attached to the pyran ring deviates by −0.009 (1) Å. The crystal packing features C—H⋯O hydrogen bonds, forming a three-dimensional structure. The meth­oxy­carbonyl atoms are disordered over two positions, with a refined occupancy ratio of 0.508 (18):0.492 (18).

2,2′-{[2-(2-Hydroxyphenyl)-4-methylimidazolidine-1,3-diyl]bis(methylene)}diphenol

The asymmetric unit in the title compound, C24H26N2O3, comprises two independent mol­ecules (A and B). In molecule A, the central 2-hydroxyphenyl ring is inclined to the mean plane of the major component of the imidazolidine ring by 84.52 (14)°, and by 68.08 (9) and 47.48 (9)° to the outer phenol rings. The later are inclined to one another by 66.76 (9)° and by 78.12 (14) and 80.20 (14)° to the imidazoline ring mean plane. In molecule B, the central 2-hydroxyphenyl ring is inclined to the mean plane of the imidazolidine ring by 73.64 (10)°, and by 75.60 (8) and 38.32 (9)° to the outer phenol rings. The later are inclined to one another by 69.47 (9)° and by 82.60 (10) and 64.26 (10)° to the imidazolidine ring mean plane. In each of the independent mol­ecules, two intra­molecular O—H⋯N hydrogen bond form S(6) ring motifs. In disordered mol­ecule A, the O—H groups of the 2-hy­droxy­benzyl groups are also involved in intra­molecular O—H⋯O hydrogen bonds, with the O atom of the hy­droxy­phenyl group acting as the acceptor. In the crystal, A molecules are linked by pairs of O—H⋯O hydrogen bonds forming inversion dimers. These dimers are linked to the B molecules via O—H⋯O hydrogen bonds forming double-layered slabs lying parallel to the bc plane.

Synthesis and Crystal Structures of Four New Dihydropyridine Derivatives

Four new Hantzsch 1,4-dihydropyridine derivatives, dimethyl 4-(4-hydroxy-3-methoxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, (I), dimethyl 4-(4-bromophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, (II), dimethyl 4-(3-bromo-4-methoxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate, (III), and dimethyl 2-(2,5-dimethoxyphenyl)-4,6-dimethyl-1,2-dihydropyridine-3,5-dicarboxylate, (IV), have been synthesized and examined by X-ray crystallography, B3LYP/6-31 G (d) molecular orbital calculations and Hirshfeld surface and fingerprint plots. (I), C18H20NO6, is monoclinic with space group P21/n and cell constants a = 9.60810(10) A, b = 7.41900(10) A, c = 24.1821(3) A, = 94.1970(10)°, V = 1719.14(4) A3, and Z = 4. (II), C17H15BrN2O6, is orthorhombic with space group P212121 and cell constants a = 11.8865(5) A, b = 13.1157(4) A, c = 21.9515(9) A, V = 3422.2(2) A3, and Z = 8. (III), C18H20BrNO5, is orthorhombic with space group Pbca and cell constants a = 8.55470(10) A, b = 15.5248(2) A, 27.0657(5) A, V = 3594.60(9) A3, and Z = 8. (IV), C19H23NO6, is orthorhombic with space group Pbca and cell constants a = 11.6798(3) A, b = 13.6319(3) A, 23.0976(5) A, V = 3677.55(15) A3, and Z = 8. The first three have the same 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate skeleton with different substituted phenyl ligands attached to the 4-site of the dihydropyridine ring. The fourth derivative (IV) consists of a related 4,6-dimethyl-1,2-dihydropyridine-3,5-dicarboxylate skeleton with 2,5-dimethoxyphenyl and methyl ligands attached to the 2 and 4 sites of the 1,2-dihydropyridine ring. The dihedral angle between the mean planes of the dihydropyridine and benzene rings is 89.6(2)° (I), 86.0(6)° or 87.2(9)° (II), 87.7(6)° (III), and 87.3(8)° (IV), respectively. O–H··· (I), N–H···O (II), N–H···O (IV) hydrogen bonds and weak N–H···O, C–H···O (I), C–H···O (II), N–H···O (III), C–H···O (IV) intermolecular hydrogen bond interactions help stabilize crystal packing in each of their unit cells. A comparison of the angles between mean planes of the benzene rings in the crystals and with the DFT theoretical calculation as well as inclusion of weak intermolecular hydrogen bond interactions has been included for each molecule. Hirshfeld surface analysis for visually analyzing intermolecular interactions in crystal structures employing 3D molecular surface contours and 2D fingerprint plots have also been used to examine molecular shapes. Molecular orbital diagrams provide visual representations of the top level molecular orbital surfaces in each compound. Synthesis, crystal structures, density functional theory (DFT), Hirshfeld and molecular orbital surface calculations of four new dihydropyridine derivitives.

Allyl 2-(2,2-dimethyl-3a,6a-di-hydro-furo[3,2-d][1,3]dioxol-5-yl)-4-oxo-4H-chromene-3-carboxyl-ate.

In the title compound, C20H18O7, the dioxolane ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap, and its mean plane makes a dihedral angle of 73.25 (2)° with the pyran ring mean plane. The furan ring makes dihedral angles of 67.43 (12) and 6.20 (11)° with the mean plane of the dioxolane and pyran rings, respectively. The O atom attached to the pyran ring deviates by 0.0219 (2) Å from its mean plane. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, forming chains along [010] and enclosing R 2 2(9) loops. They stack along the a axis with π–π inter­actions involving the 4H-chromene units [centroid–centroid distances of 3.6389 (13) and 3.6555 (13) Å]. The terminal CH2=CH- atoms of the allyl acetate group are disordered over two sets of sites with a refined occupancy ratio of 0.717 (6):0.283 (6).

2,2′-{[2-(2-Chlorophenyl)-4-methylimidazolidine-1,3-diyl]bis(methylene)}diphenol

In the title compound, C24H25ClN2O2, the 2-hy­droxy­benzyl substituents and the 2-chloro­phenyl group occupy the sterically preferred equatorial positions, whereas the methyl group occupies the axial position. The imidazolidine ring adopts an envelope conformation with one of the N atoms adjacent to the methylene group as the flap. The chloro­phenyl substit­uent approaches a nearly perpendicular orientation relative to the mean plane of the imidazolidine ring, making a dihedral angle of 73.44 (12)° and the Cl atom is almost coplanar with the C atom bearing the chloro­phenyl substituent [Cl—C—C—C torsion angle = 1.1 (3)°]. The hy­droxy­benzyl groups make dihedral angles of 71.23 (15) and 69.13 (19)° with the mean plane of the heterocyclic ring. The dihedral angle between the two hy­droxy­benzyl groups is 69.61 (12)°. The mol­ecular structure features two intra­molecular O—H⋯N hydrogen bonds with graph-set motif S(6) between the phenolic hydroxyl groups and N atoms.

Methyl 3′-benzyl-4′-(2-chlorophenyl)-1′-methyl-2-oxospiro[indoline-3,2′-pyrrolidine]-3′-carboxylate

In the title compound, C27H25ClN2O3, the methyl­pyrrolidine ring adopts an envelope conformation with the N atom at the flap. The mean plane of the pyrrolidine ring makes dihedral angles of 82.1 (1), 84.4 (1) and 79.8 (1)°, respectively, with the adjacent benzene ring, the mean plane of the indoline ring system and the phenyl ring. The mol­ecular structure is stabilized by intra­molecular C—H⋯O hydrogen bonds. In the crystal, mol­ecules are linked into chains along [101] by N—H⋯O hydrogen bonds. C—H⋯π inter­actions are observed between the chains.