Hexa­methyl­enetetraminium 2,4,6‐tri­nitro­phenolate

In the title complex, the 1:1 ionic adduct of hexa­methyl­enetetraminium and 2,4,6‐tri­nitro­phenolate, C₆H₁₃N₄⁺·­C₆H₂N₃O₇^?, the cation acts as a donor for bifurcated hydrogen bonds to the O atoms of the phenolate and one of the nitro groups of the 2,4,6‐tri­nitro­phenolate anion. The crystal structure is built from sheets of cations and anions, and is stabilized by intermolecular C—H?O and C—H?π interactions.     

Precursor of a β‐lactamase inhibitor: allyl (4S,8S,9R)‐10‐[(E)‐ethyl­idene]‐4‐methoxy‐11‐oxo‐1‐aza­tri­cyclo­[7.2.0.03,8]­undec‐2‐ene‐2‐carboxyl­ate

The molecular structure of the title tricyclic compound, C₁₇H₂₁NO₄, which is the immediate precursor of a potent synthetic inhibitor {Lek157: sodium (8S,9R)‐10‐[(E)‐ethyl­idene]‐4‐methoxy‐11‐oxo‐1‐aza­tri­cyclo­[7.2.0.0^3,8]­undec‐2‐ene‐2‐carboxyl­ate} with remarkable potency, provides experimental evidence for the previously modelled relative position of the fused cyclo­hexyl ring and the carbonyl group of the β‐lactam ring, which takes part in the formation of the initial tetrahedral acyl–enzyme complex. In this hydro­phobic mol­ecule, the overall geometry is influenced by C—H?O intramolecular hydrogen bonds [3.046 (4) and 3.538 (6) Å, with corresponding normalized H?O distances of 2.30 and 2.46 Å], whereas the mol­ecules are interconnected through intermolecular C—H?O hydrogen bonds [3.335 (4)–3.575 (5) Å].     

Hexa­methyl­enetetra­mine–4‐nitro­catechol–water (1/2/1)

In the title adduct, 1,3,5,7‐tetra­aza­tri­cyclo[3.3.1.1^3,7]dec­ane–4‐nitro­benzene‐1,2‐diol–water (1/2/1), C₆H₁₂N₄·2C₆H₅NO₄·H₂O, the hexa­methyl­ene­tetra­mine mol­ecule acts as an acceptor of intermolecular O—H?N hydrogen‐bonding interactions from the water mol­ecule and the hydroxy groups of one of the two symmetry‐independent 4‐nitro­catechol mol­ecules. The structure is built from molecular layers which are stabilized by three intermolecular O—H?O, two intermolecular O—H?N and four intermolecular C—H?O hydrogen bonds. The layers are further interconnected by one additional intermolecular O—H?N and two intermolecular C—H?O hydrogen bonds.     

Hydrogen bonding in C‐substituted nitroanilines: molecular ladders in 2‐trifluoromethyl‐4‐nitroaniline and sheets of R(12) and R(32) rings in 3‐trifluoromethyl‐4‐nitroaniline

In 2‐tri­fluoro­methyl‐4‐nitro­aniline, C₇H₅F₃N₂O₂, (I), the mol­ecules lie across a mirror plane in space group Pnma. The mol­ecules are linked by paired N—H?O hydrogen bonds to form a C(8)[R(6)] chain of rings, pairs of which are linked into a molecular ladder by a single C—H?O hydrogen bond. The isomeric 3‐tri­fluoro­methyl‐4‐nitro­aniline, (II), has Z′ = 2 in space group P2₁/c. Each mol­ecule is linked to four others by N—H?O hydrogen bonds to form sheets built from alternating R(12) and R(32) rings.     

Two bis­(ammonium) 1,5‐naphthalene­disulfonate salts

The title compounds, bis­(ammonium) naphthalene‐1,5‐di­sul­fon­ate, 2NH₄⁺·C₁₀H₆O₆S₂²⁻, and bis­[1‐(hydroxy­methyl)‐3,5,7‐tri­aza‐1‐azoniatri­cyclo­[3.3.1.1^3,7]­decane] 1,5‐naphthalene­di­sul­fon­ate, 2C₇H₁₅N₄O⁺·C₁₀H₆O₆S₂²⁻, were prepared from the acid‐promoted reaction of hexa­methyl­enetetr­amine. In both structures, the di­sulfonate anion is positioned on an inversion center, with each sulfonate group contributing to the supramolecular assemblies via hydrogen bonds. The ammonium cations are linked to sulfonate groups by four distinct N⁺—H⃛⁻O—S contacts [N⃛O = 2.846 (2)–2.898 (2) Å and N—H⃛O = 160 (2)–175 (2)°], whereas the 1‐(hydroxy­methyl)‐3,5,7‐tri­aza‐1‐azoniatri­cyclo­[3.3.1.1^3,7]­decane cations form one O—H⃛⁻O—S [O⃛O = 2.628 (2) Å and O—H⃛O = 176°] and three C—H⃛⁻O—S [C⃛O = 3.359 (2)–3.380 (2) Å and C—H⃛O = 148–155°] interactions to neighboring sulfonate groups.     

Tetrameric triphenylsilanol, (Ph3SiOH)4, and the adduct (Ph3SiOH)2–di­methyl sulfoxide,both at 120 K,and the adduct (Ph3SiOH)4–1,4‐dioxan at 150 K: interplay of O—H⋯O and C—H⋯π(arene) interactions

The structure of tetrameric tri­phenyl­silanol, C₁₈H₁₆OSi, (I), has been re‐investigated at 120 (2) K. The hydroxyl H atoms were readily located and one of the arene rings is disordered over two closely positioned sets of sites. The mol­ecules are linked into cyclic tetramers, having approximate (S₄) symmetry, via O—H?O hydrogen bonds [H?O 1.81–1.85 Å, O?O 2.634 (3)–2.693 (3) Å and O—H?O 156–166°]. At ambient temperature, there are indications of multiple disorder of the phenyl‐ring sites. In bis­(tri­phenyl­silanol) di­methyl sulfoxide solvate, 2C₁₈H₁₆OSi·C₂H₆OS, (II), the di­methyl sulfoxide component is disordered across a twofold rotation axis in C2/c, and the molecular components are linked by a single O—H?O hydrogen bond [H?O 1.85 Å, O?O 2.732 (2) Å and O—H?O 172°] into three‐mol­ecule aggregates, which are themselves linked into a single three‐dimensional framework by two C—H?π(arene) interactions. In tetrakis­(tri­phenyl­silanol) 1,4‐dioxan solvate, 4C₁₈H₁₆OSi·C₄H₈O₂, (III), the 1,4‐dioxan component lies across an inversion centre in space group P and centrosymmetric five‐mol­ecule aggregates are linked by paired C—H?π(arene) interactions to form molecular ladders.     

A new tribridged imidazolium cyclo­phane

The new imidazolium cyclo­phane 2,11,13,21,29,31‐hexamethyl‐5,16,24‐tri­aza‐8,19,27‐triazoniahepta­cyclo[10.10.6.1^1,3.­1^5,8.1^10,14.1^16,19.1^24,27]­tritriaconta‐1,3(29),6,8(30),10,­12,14(31),17,19(32),21,25,27(33)‐dodecene tri­bromide dihydrate, C₃₃H₃₉N₆³⁺.3Br^?.2H₂O, belongs to a type of cyl­indrical macrobicyclic salt containing imidazolium groups. It has mirror symmetry, the symmetry surface is the plane of the three 2‐C atoms of imidazoliums. Three bromine anions are associated with two water mol­ecules by hydrogen bonds. The O—H?Br bond lengths are 2.53 (3) and 2.46 (3) Å.     

The dimeric mixed‐ligand titana­carborane sandwich [1‐(Cp)‐1‐Ti‐2‐(Me)‐3‐(SiMe3)‐2,3‐C2B4H4]2

The title dimer, bis­[1‐cyclo­penta­dienyl‐2‐methyl‐1‐titana‐3‐tri­methylsilyl‐2,3‐dicarba‐closo‐hexaborane(6)], [Ti(C₅H₅)(C₆­H₁₆­B₄Si)]₂, reveals that the centrosymmetric mol­ecule consists of two bent‐sandwich titanacarboranes bridged by the B—H—Ti bonds. The average bond distances are Ti—B 2.445 (3), Ti—C(cage) 2.334 (2) and Ti—C(Cp) 2.376 (3) Å, and the corresponding bond angles are Cp—Ti—Cp 163.2 (1) and Cp—Ti—Cb (Cb = C₂B₃ face) 139.9 (1)°; the Ti—H separations are 2.10 (2) and 2.19 (2) Å.     

Two‐component molecular crystals composed of chloronitrobenzoic acids and 4‐aminopyridine

The crystal structures of the four isomeric organic salts 4‐amino­pyridinium 2‐chloro‐4‐nitro­benzoate, (I), 4‐amino­pyridinium 2‐chloro‐5‐nitro­benzoate, (II), 4‐amino­pyridinium 5‐chloro‐2‐nitro­benzoate, (III), and 4‐amino­pyridinium 4‐chloro‐2‐nitro­benzoate, (IV), all C₅H₇N₂⁺·C₇H₃ClNO₄^?, are presented. Compound (I) has one intramolecular hydrogen bond, one intermolecular C—H?O hydrogen bond and π–π‐stacking interactions. Compound (II) has N—H?O, C—H?O and C—H?Cl hydrogen bonds, and Cl?O—C electrostatic interactions. Compound (III) has N—H?O and C—H?O hydrogen bonds. Compound (IV) has a π–π‐stacking interaction, but no C—H?O hydrogen bonds.     

(1R,3S)‐1‐Mono­amido­camphoric acid

The title compound, (1S,3R)‐3‐carbamoyl‐2,2,3‐tri­methyl­cyclo­pentane‐1‐carboxyl­ic acid, C₁₀H₁₇NO₃, was synthesized and characterized by IR, EA, ES–MS (electrospray ionization mass spectra), ¹H NMR, ¹³C NMR and X‐ray diffraction techniques. The two independent mol­ecules form a two‐dimensional network via O—H⃛O and N—H⃛O hydrogen‐bonding interactions between their carbox­ylic acid and carbamoyl groups.     

1‐(4‐Chloro­phenyl­sulfanyl)‐2‐nitro‐4‐(tri­fluoro­methyl)­benzene and 1‐(4‐chloro­phenyl­sulfanyl)‐4‐nitro‐2‐(tri­fluoro­methyl)­benzene

Two chemical isomers of 3‐nitro­benzotrifluoride, namely 1‐(4‐chloro­phenyl­sulfanyl)‐2‐nitro‐4‐(tri­fluoro­methyl)­benzene, C₁₃H₇ClF₃NO₂S, (I), and 1‐(4‐chloro­phenyl­sulfanyl)‐4‐nitro‐2‐(tri­fluoro­methyl)­benzene, C₁₃H₇ClF₃NO₂S, (II), have been prepared and their crystal structures determined with the specific purpose of forming a cocrystal of the two. The two compounds display a similar conformation, with dihedral angles between the benzene rings of 83.1 (1) and 76.2 (1)°, respectively, but (I) packs in P while (II) packs in P2₁/c, with C—H⋯O interactions. No cocrystal could be formed, and it is suggested that the C—H⋯O associations in (II) prevent intermolecular mixing and promote phase separation.     

(4‐Nitrophenylsulfanylmethyl)triphenylstannane and (4‐nitrophenylsulfonylmethyl)triphenylstannane: R(X) rings (X is 10, 18 or 24) and C—H⋯π interactions

In the crystal structures of (4‐nitro­phenyl­sulfanyl­methyl)­tri­phenyl­stannane, [Sn(C₆H₅)₃(C₇H₆NO₂S)], (I), and (4‐nitro­phenyl­sulfonyl­methyl)­tri­phenyl­stannane, [Sn(C₆H₅)₃­(C₇H₆NO₄S)], (II), the mol­ecules are linked by paired C—H?O hydrogen bonds into centrosymmetric dimers which combine to form sheets. In (I), two such dimers form to give R(10) and R(24) rings. In (II), similar dimers form, here with R(10) and R(18) rings, but with an additional dimer due to the presence of the sulfone group, giving R(10) rings. In both structures, C—H?π interactions lead to a doubling of the width of the sheets.     

Ethyl 6‐acetylamino‐6,7‐dihydro‐5H‐dibenzo[a,c]cycloheptene‐6‐carboxylate

The title compound, C₂₀H₂₁NO₃, is a derivative of Aib (α‐­aminoisobutyric acid) and is cyclized at the C^α position by bi­phenyl rings. The seven‐membered ring possesses C2 symmetry. The C^α cyclization causes the backbone to assume a helical conformation in the crystal structure. The packing of the mol­ecules is stabilized by intermolecular C—H?O, C—H?π and N—H?O hydrogen bonds.     

Bis­[1,3‐bis­(tri­methyl­silyl)­allyl]­cobalt(II), a stable electron‐deficient allyl complex

The title compound, bis­[(1,2,3‐η)‐(2E)‐1,3‐bis­(tri­methyl­silyl)­prop‐2‐enyl]­cobalt(II), [Co(C₉H₂₁Si₂)₂], is a homoleptic allyl complex with η³‐bound ligands. The Co—C distances range from 1.996 (3) to 2.096 (3) Å and the allyl ligands adopt staggered, nearly parallel, arrangements around the Co atom. The tri­methyl­silyl groups are in syn–anti conformations; the steric shielding they provide to the metal is probably responsible for the thermal stability of the compound.     

Di­cyclo­hexyl­ammonium 2,4‐di­chloro­phenoxy­acetate and (2,4‐di­chloro­phenoxy­acetato‐O,O′)bis­(tri­phenylphosphine‐P)silver(I)

The monoclinic cell of di­cyclo­hexyl­ammonium 2,4‐di­chloro­phenoxy­acetate contains four C₁₂H₂₄N⁺·C₅H₈Cl₂O₃^? ion pairs. The ammonium N atom is hydrogen bonded to the oxy­gen ends of two carboxyl groups to form a 12‐membered O—C—O?HNH?O—C—O?HNH ring. In (2,4‐di­chloro­phenoxy­lacetato)­bis­(tri­phenyl­phosphine)silver(I), [Ag(C₈H₅Cl₂O₃)(C₁₈H₁₅P)₂], the carboxyl CO₂ unit chelates to the Ag atom in an anisobidentate manner [Ag—O = 2.436 (2) and 2.517 (2) Å]; the Ag atom shows distorted tetrahedral geometry.     

Hydrogen bonding in two salts of 3‐methylthio‐4‐(propargylthio)quinoline

In 3‐methyl­thio‐4‐(propargyl­thio)­quinolinium chloride monohydrate, C₁₃H₁₂NS₂⁺·Cl^?·H₂O, and 3‐methyl­thio‐4‐(propargyl­thio)­quinolinium tri­chloro­acetate, C₁₃H₁₂­NS₂⁺·­C₂Cl₃O₂^?, the terminal alkyne group forms C[triple‐bond]C—H?O hydrogen bonds of favourable geometry. The conformation of the flexible propargyl­thio group is different in the two structures.     

N‐Fluoropyridinium trifluoromethanesulfonate and 1‐fluoro‐2,4,6‐trimethoxy‐1,3,5‐triazinium hexafluoroantimonate: the first experimental determination of the F—N+ bond length involving sp2 nitrogen

The structures of N‐fluoro­pyridinium tri­fluoro­methane­sulfon­ate, C₅H₅FN⁺·CF₃O₃S⁻, (I), and 1‐fluoro‐2,4,6‐tri­methoxy‐1,3,5‐triazinium hexa­fluoro­antimonate, (C₆H₉FN₃O₃)[SbF₆], (II), are presented. The N—F bond lengths in (I), a well known electrophilic fluorinating agent, and its novel analogue, (II), are 1.357 (4) and 1.354 (4) Å, respectively.     

A cyano‐bridged dinuclear 4f–3d array

A cyano‐bridged bimetallic 4f–3d complex, tri­aqua‐1κ³O‐μ‐cyano‐1:2κ²N:C‐penta­cyano‐2κ⁵C‐tetrakis(2‐pyrrolidone‐1κO)­chromium(III)­dysprosium(III) dihydrate, [CrDy(C₄H₇NO)₄(CN)₆(H₂O)₃]·2H₂O, has been prepared and characterized by X‐ray crystallographic analysis. The structure consists of a neutral cyano‐bridged Dy–Cr dimer. A hydrogen‐bonded three‐dimensional architecture is formed through N—H?O, O—H?N and O—H?O hydrogen bonds.     

Conformation of cationic N,N‐di­methyl­glycine in di­methyl­glycinium tri­fluoro­acetate

In the title compound, C₄H₁₀NO₂⁺·C₂F₃O₂^?, the main N—C—COOH skeleton of the protonated amino acid is nearly planar. The C=O/C—N and C=O/O—H bonds are syn and the two methyl groups are gauche to the methyl­ene H atoms. The conformation of the cation in the crystal is compared to that given by ab initio calculations (Hartree–Fock, self‐consistent field molecular‐orbital theory). The tri­fluoro­acetate anion has the typical staggered conformation with usual bond distances and angles. The cation and anion form dimers through a strong O—H?O hydrogen bond which are further interconnected in infinite zigzag chains running parallel to the a axis by N—H?O bonds. Weaker C—H?O interactions involving the methyl groups and the carboxy O atoms of the cation occur between the chains.     

A ternary complex of aqua(18‐crown‐6)bis(o‐nitrophenolato)barium(II), the triaqua(18‐crown‐6)(o‐nitrophenolato)barium(II) cation and the o‐nitrophenolate anion

In the title compound [systematic name: tri­aqua(1,4,7,10,13,16‐hexaoxa­cyclo­octa­decane‐κ⁶O)(2‐nitro­phenolato‐κO)­barium(II)–aqua(1,4,7,10,13,16‐hexaoxa­cyclo­octa­decane‐κ⁶O)‐ bis(2‐nitro­phenolato‐κ²O,O′)­barium(II)–2‐nitro­phenolate (1/1/1)], [Ba(C₁₂H₂₄O₆)(C₆H₄NO₃)(H₂O)₃][Ba(C₁₂H₂₄O₆)(C₆H₄NO₃)₂(H₂O)](C₆H₄NO₃), the two Ba^II atoms encapsulated by the 18‐crown‐6 rings have different coordinations. Although both Ba^II atoms are coordinated to the six O atoms of the crowns, in the neutral moiety, the Ba^II atom is coordinated to one terminal O atom from a water mol­ecule, two phenolate O atoms and two nitro‐group O atoms, while in the cationic moiety, the Ba^II atom is coordinated to three terminal O atoms from water mol­ecules and one phenolate O atom. Both the crowns are eclipsed and translated along the b direction. In the asymmetric unit, the three components are interconnected by four O—H?O interactions. The packing is stabilized by two intermolecular C—H?O interactions and by one O—H?O interaction.