Cyclic and acyclic products from the reactions between methyl 3-oxobutanoate and arylhydrazines

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1-[2-(Carboxymethoxy)phenyl]-N-(4-chlorophenyl)methanimine oxide

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2-Amino-3-chloro-5-nitro­benzamide

The amide group in the title compound, C7H6ClN3O3, is significantly twisted out of the plane of the benzene ring [C—C—C—O = 34.2 (5)°] whereas the nitro group is almost co-planar [O—N—C—C = 4.0 (5)°] with the ring. Intra­molecular N—H⋯O and N—H⋯Cl hydrogen bonds occur. In the crystal, the mol­ecules are linked by N—H⋯O hydrogen bonds, generating layers propagating in the ab plane

2-(2-Amino-4-nitrophenyl)-7-nitro-4H-3,1-benzoxazin-4-one

The use of the EPSRC X-ray crystallographic service (Coles & Gale, 2012[Coles, S. J. & Gale, P. A. (2012). Chem. Sci. 3, 683-689.]) at the University of Southampton, England, and the valuable assistance of the staff there is gratefully acknowledged. JLW acknowledges support from CAPES (Brazil). Structural studies are supported by the Ministry of Higher Education (Malaysia) and the University of Malaya through the High-Impact Research scheme (UM.C/HIR/MOHE/SC/3).Peer reviewedPublisher PD

A kryptoracemic salt: 2-{[2,8-bis(trifluoromethyl)quinolin-4yl](hydroxy)methyl}piperidin-1-ium (+)-3,3,3-trifluoro-2-methoxy-2-phenylpropanoate

The asymmetric unit of the title salt, C17H17F6N2O+·C10H8F3O3-, comprises two piperidin-1-ium cations and two carboxyl­ate anions. The cations, each having an L-shaped conformation owing to the near orthogonal relationship between the quinolinyl and piperidin-1-ium residues, are pseudo-enanti­omeric. The anions have the same absolute configuration but differ in the relative orientations of the carboxyl­ate, meth­oxy and benzene groups. Arguably, the most prominent difference between the anions occurs about the Cq-Om bond as seen in the Cc-Cq-Om-Cm torsion angles of -176.1 (3) and -67.1 (4)°, respectively (q = quaternary, m = meth­oxy and c = carboxyl­ate). The presence of Oh-H...Oc and Np-H...Oc hydrogen bonds leads to the formation of a supra­molecular chain along the a axis (h = hy­droxy and p = piperidin-1-ium); weak intra­molecular Np-H...Oh hydrogen bonds are also noted. Chains are connected into a three-dimensional architecture by C-H...F inter­actions. Based on a literature survey, related mol­ecules/cations adopt a uniform conformation in the solid state based on the letter L

Crystal structures of the 1:1 salts of 2-amino-4-nitrobenzoate with each of (2-hydroxyethyl)dimethylazanium, tert-butyl(2-hydroxyethyl)azanium and 1,3-dihydroxy-2-(hydroxymethyl)propan-2-aminium

The crystal and molecular structures of the title molecular salts,C4H12NO+C7H5N2O4, (I), C6H16NO+C7H5N2O4, (II), and C4H12NO3+-C7H5N2O4, (III), are described. The common feature of these salts is thepresence of the 2-amino-4-nitrobenzoate anion, which exhibit non-chemicallysignificant variations in the conformational relationships between the carboxylate and nitro groups, and between these and the benzene rings they are connected to. The number of ammonium-N—H H atoms in the cations increases from one to three in (I) to (III), respectively, and this variation significantly influences the supramolecular aggregation patterns in the respective crystals. Thus, a linear supramolecular chain along [100] sustained by charge-assisted tertiary-ammonium-N—HO(carboxylate), hydroxy-O—HO(carboxylate) and amino-N—HO(carboxylate) hydrogen-bonds is apparent in the crystal of (I). Chains are connected into a three-dimensional architecture by methyl-C—HO(hydroxy) and – interactions, the latter between benzene rings [intercentroid separation = 3.5796 (10) A˚ ]. In the crystal of (II), a supramolecular tube propagating along [901] arises as a result of charge-assisted secondaryammonium-N—HO(carboxylate) and hydroxy-O—HO(carboxylate) hydrogen-bonding. These are connected by methylene- and methyl-C— HO(nitro) and – stacking between benzene rings [inter-centroid separation = 3.5226 (10) A˚ ]. Finally, double-layers parallel to (100) sustained by charge-assisted ammonium-N—HO(carboxylate), ammonium-N—H O(hydroxy) and hydroxy-O—HO(carboxylate) hydrogen-bonds are apparent in the crystal of (III). These are connected in a three-dimensional architecture by amine-N—HO(nitro) hydrogen-bonds

1-(4-Methyl­phen­yl)-3-phenyl-1H-pyrazol-5-yl 4-nitro­benzene­sulfonate

In the title mol­ecule, C22H17N3O5S, the pyrazole ring is planar (r.m.s. deviation = 0.018 Å) and forms dihedral angles of 21.45 (10) and 6.96 (10)° with the N- and C-bound benzene rings, respectively. Supra­molecular layers in the bc plane are formed in the crystal via C—H⋯O and π–π inter­actions involving the sulfonamide benzene ring inter­acting with the N- and C-bound benzene rings [centroid–centroid distances = 3.790 (2) and 3.730 (2) Å, respectively]. The crystal studied was found to be a merohedral twin (twin law 1 0 0.678, 0 -1 0, 0 0 -1), the fractional contribution of the minor component being approximately 36%

1-Iodo-4-meth­oxy-2-nitro­benzene

In the title compound, C7H6INO3, the 12 non-H atoms are planar, with an r.m.s. deviation of 0.016 Å. A close intra­molecular I⋯O inter­action [3.0295 (13) Å] is present. Inter­molecular I⋯O inter­actions [3.3448 (13) Å] lead to the formation of zigzag chains along the b axis. These are assembled into layers by weak π–π inter­actions [centroid–centroid distance = 3.8416 (9) Å], and the layers stack along the a axis, being connected by C—H⋯O contacts

7-Chloro-4-[(7-chloro­quinolin-4-yl)sulfan­yl]quinoline dihydrate

In the title thio­ether dihydrate, C18H10Cl2N2S·2H2O, the S-bound quinolinyl residues are almost orthogonal, forming a dihedral angle of 72.36 (4)°. In the crystal, the four water mol­ecules are connected via an eight-membered {⋯OH}4 synthon with each of the four pendent water H atoms hydrogen bonded to a pyridine N atom to stabilize a three-dimensional architecture

Crystal structures of potassium tri­fluorido­(4-meth­oxy­phen­yl)borate and potassium tri­fluorido(4-fluoro­phen­yl)borate

Acknowledgements We thank the National Crystallography Service (University of Southampton) for the data collections.Peer reviewedPublisher PD