1,2-Bis[(1,3-benzodioxol-5-yl)methyl­idene]hydrazine

The complete mol­ecule of the title compound, C₁₆H₁₂N₂O₄, is generated by the application of a centre of inversion. The (1,3-benzodioxol-5-yl)methyl­idene fused-ring system is approximately planar (r.m.s. deviation = 0.020 Å) and is essentially coplanar with the central hydrazine group [dihedral angle = 5.08 (9)°]. Weak π–π inter­molecular inter­actions are observed [centroid–centroid distance = 3.8553 (8) Å], providing some packing stability.

1,2-Bis(3-phen­oxy­benzyl­idene)hydrazine

Mol­ecules of the title compound, C₂₆H₂₀N₂O₂, reside on crystallographic centres of inversion located at the mid-point of the N—N bond. The benzyl­idene ring is essentially coplanar with the central hydrazine group, with an inter­planar angle of 4.5 (2)°, whereas the phenyl ring is oriented at 34.0 (3)° with respect to the mean plane of the central 1,2-dibenzyl­idenehydrazine group. In the crystal, C—H...π(arene)-ring inter­actions link mol­ecules about inversion centres.

N-(4,6-Dimeth­oxy­pyrimidin-2-yl)-2-(3-methyl­phen­yl)acetamide

In the title compound, C₁₅H₁₇N₃O₃, the dihedral angle between the pyrimidine and benzene rings is 87.0 (7)°. In the crystal, mol­ecules are linked into inversion dimers with R₂²(8) graph-set motifs by a pair of N—H...O hydrogen bonds. Weak C—H...O hydrogen bonds and inter­molecular π–π inter­actions [centroid–centroid distance = 3.544 (1) Å] are also observed.

1,1'-(Ethane-1,2-di­yl)dipyridinium dichromate(VI)

In the cation of the title salt, (C₁₂H₁₄N₂)[Cr₂O₇], the two pyridinium moieties are in an anti orientation with respect to one another. The dihedral angle between the pyridine rings is 6.3 (2)°. The N-C-C-N torsion angle is 177.5 (2)°. In the dianion, the Cr^VI ions are in a slightly distorted tetra­hedral coordination environment and the bond angles at the independent Cr^VI ions are in the ranges 105.93 (10)-110.60 (11) and 107.35 (11)-111.07 (12)°. The Cr-O-Cr angle is 127.96 (12)°. The crystal used was an inversion twin with refined components of 0.510 (19) and 0.490 (19).

1,3-Bis(biphenyl-4-yl)-2,2-dibromo-3-oxopropyl acetate

In the title compound, C₂₉H₂₂Br₂O₃, the dihedral angles between the mean planes of the benzene rings within each biphenyl group are 26.7 (8) and 30.9 (8)°. The mean planes of the terminal and inner benzene rings of the biphenyl groups bonded through a propan-1-one group in the V-shaped mol­ecule are oriented at angles of 66.1 (7) and 60.0 (8)°, respectively. The two Br atoms are opposite the propen-1-one group. Weak inter­molecular C—H...O and C—H...π inter­actions are observed in the crystal structure.

3,3-Dimethyl-1,2,3,4-tetra­hydro­cyclo­penta­[b]indole-1,2-dione (bruceolline E)

The title compound, C₁₃H₁₁NO₂, crystallizes with two mol­ecules in the asymmetric unit. The crystal packing is stabilized by N—H...O hydrogen bonds, which link the mol­ecules into chains along [10], and weak C—H...O inter­actions.

(2E)-1-(3,4-Dichloro­phen­yl)-3-(2-hy­droxy­phen­yl)prop-2-en-1-one

In the title compound, C₁₅H₁₀Cl₂O₂, the dihedral angle between the mean planes of the two benzene rings is 7.7 (6)°. The crystal packing is influenced by O—H...O hydrogen bonds, which form chains along [010]. Weak π–π stacking inter­actions [centroid–centroid distance = 3.6697 (13) Å] are observed, which may contribute to the crystal packing stability.

Ethyl 2-amino-4,6-bis­(4-fluoro­phen­yl)cyclo­hexa-1,3-diene-1-carboxyl­ate

In the title compound, C₂₁H₁₉F₂NO₂, the cyclo­hexa-1,3-diene ring is in a distorted envelope conformation. The dihedral angles between the mean planes of the diene moiety and the two fluoro­phenyl rings are 42.8 (2) and 75.0 (5)°. The two fluoro­phenyl rings are inclined to one another by 87.0 (3)°. In the crystal, intra­molecular N—H...O hydrogen bonds and weak N—H...O and N—H...F inter­molecular inter­actions are observed forming an infinite two-dimensional network along [011].

(6Z)-3,5-Bis(4-fluoro­phen­yl)-6-(1-hy­droxy­ethyl­idene)cyclo­hex-2-en-1-one

In the title compound, C₂₀H₁₆F₂O₂, the cyclo­hex-2-en-1-one ring adopts a distorted envelope conformation and the dihedral angles between its six-atom mean plane and the fluorophenyl rings are 38.9(8) and 82.3(1)°. The two fluoro­phenyl rings are oriented at an angle of 77.3 (3)°. The long hy­droxy O—H bond length of 1.22 (3) and the H...O distance of 1.28 (3) Å, together with a longer than expected C=O bond length [1.290 (2) Å] in the hy­droxy(en-1-one) group, indicate sharing of the H atom as O...H...O between the two O atoms and the influence of electron delocalization. Weak C—H...O inter­molecular inter­actions form an infinite two-dimensional network in (011).

(2E)-1-(2,6-Dichloro-3-fluoro­phen­yl)-3-(4-meth­oxy­phen­yl)prop-2-en-1-one

There are two independent mol­ecules in the asymmetric unit of the title compound, C₁₆H₁₁Cl₂FO₂. The F atom equally populates both meta positions of the 6-dichloro-3-fluoro­phenyl ring in each mol­ecule, resulting in 0.5 occupancy for both the F and H atoms in these positions. The dihedral angle between the mean planes of the benzene rings are 77.5 (2) and 89.8 (8)°in the two mol­ecules. In the crystal, weak C—H...F and C—H...O inter­actions involving the half-occupied H and F atoms are observed. Weak π–π stacking inter­actions [centroid—centroid distance = 3.150 (2) Å] also contribute to the crystal stability.

Cyclo­hexyl­ammonium acetate–N,N′,N′′-tricyclo­hexyl­phospho­ric triamide (1/1)

In the phospho­ric triamide mol­ecule of the title compound, C₆H₁₄N⁺·C₂H₃O₂⁻·C₁₈H₃₆N₃OP, the P atom displays a distorted tetra­hedral geometry and the cyclo­hexyl rings adopt chair conformations with the NH groups in equatorial positions. In the crystal, the cations, anions and phosphoric triamide mol­ecules are linked via N—H...O hydrogen bonds into a two-dimensional array parallel to the bc plane. The O atom of the P(O) group acts as a double-hydrogen-bond acceptor.

A second monoclinic polymorph of N-[bis­(morpholin-4-yl)phosphino­yl]-4-fluoro­benzamide with the P2₁/n space group

A second monoclinic polymorph of the title mol­ecule, C₁₅H₂₁FN₃O₄P, is reported in the space group P2₁/n and compared to the previously reported C2/c space group [Gholivand et al. (2006). Polyhedron, 25, 711–721]. The asymmetric unit of the title compound consists of two independent mol­ecules. The P atoms adopt a distorted tetra­hedral environment. In the C(O)NHP(O) fragment, the P=O and the N—H groups are in a syn conformation with respect to each other and in the crystal, inter­molecular N—H...O=P hydrogen bonds form dimeric aggregates.

N,N-Dimethyl-N',N''-bis­(2-methyl­phenyl)phospho­ric triamide mono­hydrate

In the title compound, C₁₆H₂₂N₃OP·H₂O, the P atom adopts a distorted tetra­hedral environment with the bond angles around the P atom in the range 99.98 (7)-116.20 (7)°. The P-N bond length in the [(CH₃)₂N]P(O) fragment [1.6392 (14) Å] is slightly shorter than two other P-N bonds [1.6439 (15) and 1.6530 (14) Å]. In the (CH₃)₂NP(O) fragment, one of the methyl groups is syn to the P=O bond, whereas the other one is anti to the P=O bond [C-N-P=O torsion angles = 4.80 (17) and -174.57 (15)°]. In the crystal, the water mol­ecules form hydrogen bonds to the O atoms of the P=O bond of two different mol­ecules and act as acceptors for the two amino H atoms of the same mol­ecule. As a result, chains parallel to [010] are formed.

Bis(pyrrolidin-1-yl)phosphinic (2,4-di­fluoro­benzo­yl)amide

The P atom in the title mol­ecule, C₁₅H₂₀F₂N₃O₂P, is in a distorted tetra­hedral P(O)(N)(N)₂ environment. The phosphoryl group and the NH unit adopt a syn orientation with respect to each other. An F atom at position 2 and an H atom at position 6 are found to occupy similar sites in a 0.70:0.30 ratio and were refined with fixed occupancies. The pyrrolidin-1-yl rings are disordered over two sets of sites, with site occupancies of 0.566 (6) and 0.434 (6), and were refined using a two-part model. In the crystal, hydrogen-bonded dimers linked by pairs of N—H...O(P) hydrogen bonds generate an R₂²(8) ring motif.

1-Butyl-3-ethyl-1H-benzimidazol-3-ium tetra­fluoro­borate

In the title salt, C₁₃H₁₉N₂⁺·BF₄⁻, an ionic liquid, the butyl and ethyl substituents bonded to the N atoms of the imidazole ring [r.m.s. deviation = 0.019 (1) Å] adopt equatorial positions. The crystal structure exhibits slipped π–π inter­actions between the imidazole and benzene rings of neighbouring mol­ecules [centroid–centroid distance = 3.529 (2) Å]. In the tetra­fluoro­borate anion, the B and F atoms are disordered over two sets of sites with site-occupancy factors of 0.813 (7) and 0.187 (7).

N,N,N′,N′-Tetra­benzyl-N′′-(2,6-difluoro­benzo­yl)phospho­ric triamide

In the C(O)NHP(O) fragment of the title compound, C₃₅H₃₂F₂N₃O₂P, the P—N bond is longer and the O—P—N angle is contracted compared with the other two P—N bonds and O—P—N angles. The P atom adopts a distorted tetra­hedral environment and the phosphoryl and carbonyl groups are anti with respect to each other. The two tertiary N atoms of the dibenzyl­amido groups show sp² character with a slight deviation from planarity. In the crystal, pairs of N—H...O(P) hydrogen bonds form inversion dimers.

N-(4-Fluoro­benzo­yl)-N′,N′′-diisopropyl­phospho­ric triamide

The asymmetric unit of the title phospho­ric triamide, C₁₃H₂₁FN₃O₂P, consists of two independent mol­ecules. In each mol­ecule, the P=O group and the N—H unit belonging to the C(O)NHP(O) fragment are in a syn conformation with respect to each other. An intra­molecular N—H...O hydrogen bond occurs in each mol­ecule. The P atom adopts a distorted tetra­hedral environment. The methyl groups of an isopropyl fragment are disordered over two sets of sites with refined occupancies of 0.458 (5) and 0.542 (5). In the crystal, mol­ecules are linked through N—H...O(=P) and N—H...O(=C) hydrogen bonds into chains along [001].