The host–guest complex between cone‐25,26:27,28‐bis­(methyl­ene­dioxy)­calix­[4]­arene and di­chloro­methane

The title compound, 25,26:27,28‐bis­(methyl­ene­dioxy)­penta­cyclo­[19.3.1.1^3,7.1^9,13.1^15,19]­octacosa‐1(25)3,5,7(28),9,11,13(27),15,17,19(26),21,23‐dodecaene di­chloro­methane solvate, C₃₀H₂₄O₄·CH₂Cl₂, possesses crystallographic twofold sym­metry in both components. The calixarene shows a pinched cone conformation with an elliptical cavity, in which the guest di­chloro­methane solvent mol­ecule is accommodated. The contact distance between guest and host (H⋯ring centroid = 2.44 Å) is extremely short.     

trans‐Chloro­(methyl)­bis­(tri­cyclo­hexyl­phosphine)­platinum(II)

The crystal structure of the title compound, [PtCl(CH₃)(C₁₈H₃₃P)₂], is isostructural with various platinum(II) and palladium(II) complexes containing two bulky tri­cyclo­hexyl­phosphine ligands in a trans orientation. The Pt atom resides on an inversion centre, resulting in a 50% statistical disorder in the chloro and methyl positions. The most significant geometrical parameters are Pt—P 2.3431 (8), Pt—­Cl 2.440 (4) and Pt—C1 2.179 (13) Å, and P—Pt—P 180, P—Pt—Cl 89.15 (12) and 90.85 (12), and C—Pt—Cl 172.7 (5)°. The effective and Tolman cone angles for the tricyclohexylphosphine ligands were calculated as 160 and 162°, respectively.     

Diels–Alder adducts of maleic ­anhydride and dienes: new compounds by crystallization

We have determined the crystal structures of bi­cyclo­[2.2.1]­hept‐2‐ene‐endo‐cis‐5,6‐di­carboxyl­ic anhydride, C₉H₈O₃, (I), 1,2,3,4,7,7‐hexa­chloro­bi­cyclo­[2.2.1]­hept‐2‐ene‐endo‐cis‐5,6‐di­carboxyl­ic anhydride diethyl ether solvate, C₉H₂Cl₆O₃·0.16­C₄H₁₀O, (II), bi­cyclo­[2.2.1]­hept‐2‐ene‐endo‐cis‐5,6‐di­carboxyl­ic acid, C₉H₁₀O₄, (III), 1,2,3,4,7,7‐hexa­chloro­bi­cyclo­[2.2.1]­hept‐2‐ene‐endo‐cis‐5,6‐di­carboxyl­ic acid, C₉H₄Cl₆O₄, (IVa) and (IVb), and ethyl 1,2,3,4,7,7‐hexa­chloro‐6‐carboxybi­cyclo­[2.2.1]­hept‐2‐ene‐endo‐cis‐5‐carboxyl­ate monohydrate, C₁₁H₈Cl₆O₄·H₂O, (V). Compounds (I) and (II) were prepared by a standard Diels–Alder reaction from maleic anhydride and cyclo­penta­diene or hexa­chloro­cyclo­penta­diene, respectively. The crystal‐growing processes of these compounds led to surprising results: rapid recrystallization of (I) from diethyl ether and (II) from petroleum ether gave crystals of these compounds, however, crystallization by slow evaporation techniques using common solvents yielded new compounds in which the five‐membered heterocycle has been cleaved.     

trans‐[N,N′‐Bis­(salicyl­idene)­cyclo­hexane‐1,2‐diaminato]­nickel(II)–chloro­form (1/1)

In the title complex, trans‐{2,2′‐[cyclo­hexane‐1,2‐diyl­bis­(ni­t­rilo­methyl­idyne)]­di­phenol­ato‐κ⁴O,N,N′,O′}­nickel(II)–chloro­form (1/1), [Ni(C₂₀H₂₀N₂O₂)]·CHCl₃, the Ni atom has a square‐planar geometry, slightly tetrahedrally distorted. The Ni—N and Ni—O bonding distances are within the expected ranges for Ni–Schiff base derivatives. The di­imine bridge has a gauche conformation with the cyclo­hexyl ring almost coplanar with the NiN₂O₂ plane. The complex mol­ecules pack in dimers with an Ni?Ni distance of 3.59 (1) Å and form a three‐dimensional structure displaying a herring‐bone configuration. Channels are occupied by solvent mol­ecules, which are involved in C—H?O hydrogen bonds with the ligand O atoms.     

cis‐Di­chloro(5,8‐dioxa‐2,11‐dithia[12]‐o‐cyclo­phane)­palladium(II)

The preparation and crystal structure of the title compound, cis‐di­chloro­[6,9‐dioxa‐3,12‐di­thia­bi­cyclo­[12.4.0]­octadeca‐14,‐16,­18(1)‐tri­ene‐S,S′]­palladium(II), [PdCl₂(C₁₄H₂₀O₂S₂)], are described. The Pd atom has a square‐planar environment, coordinated to two S atoms of the di­thia­dioxa macrocycle and to two Cl^? ions. The non‐coordinating O atoms are oriented away from the metal coordination plane. Upon complexation, a bicyclic chelate structure, which consists of a seven‐ and an eleven‐membered ring, is formed.     

A dinuclear uranium(IV) complex of the chelating ligand 1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­diene

The ligand 1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­diene (cp*py) forms a dinuclear complex with U^IV, i.e. di‐μ‐oxo‐bis­{chloro­(diethyl ether‐κO)[(η⁵,κN)‐1,2,3,4‐tetra­methyl‐5‐(2‐pyridyl)­cyclo­penta­dienyl]uranium(IV)}, [U₂Cl₂O₂(C₁₄H₁₆N)₂(C₄H₁₀O)₂], in which cp*py acts as a chelating ligand, being bound to the metal atom by the cyclo­penta­dienyl unit and also by the N atom of the pyridyl ring.     

cis‐Di­chloro­[tris­(di­phenyl­phosphino­ethyl)­amine]­ruthenium(II)–chloro­form–water (1/2.5/1)

In the title compound, [RuCl₂(C₄₂H₄₂NP₃)]·2.5CHCl₃·H₂O, the Ru atom is six‐coordinated, to one tetradentate tris­(di­phenyl­phosphinoethyl)­amine ligand and two Cl atoms, in a distorted octahedral arrangement. Molecules of chloro­form and water stabilize the framework through intermolecular hydrogen bonds.     

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.     

[(1R,2R)‐1,2‐Di­amino­cyclo­hexane‐κ2N,N′](α‐di­imine‐κ2N,N′)­platinum(II) bis­(hexa­fluoro­phosphate), where α‐di­imine is 2,2′‐bi­pyridine and 1,10‐phen­anthroline

The title Pt^II complexes, viz. (2,2′‐bi­pyridine‐κ²N,N′)[(1R,2R)‐1,2‐di­amino­cyclo­hexane‐κ²N,N′]­platinum(II) bis­(hexa­fluoro­phosphate), [Pt(C₆H₁₄N₂)(C₁₀H₈N₂)](PF₆)₂, and [(1R,2R)‐1,2‐di­amino­cyclo­hexane‐κ²N,N′](1,10‐phenanthroline‐κ²N,N′)platinum(II) bis­(hexa­fluoro­phosphate), [Pt(C₆H₁₄N₂)(C₁₂H₈N₂)](PF₆)₂, containing an aromatic α‐di­imine and a non‐planar di­amino­cyclo­hexane, both form a ladder‐type structure, which is constructed via loose π–π stacking on the α‐di­imine ligands and hydrogen bonding between the cyclic amines and the counter‐anions. In the former compound, there are two independent complex cations, both of which have a twofold axis through the Pt atom.     

Cis‐ and trans‐influences in [PtCl2(SPh2)2]

Both cis‐ and trans‐di­chloro­bis­(di­phenyl ­sulfide)­platinum(II), [PtCl₂(C₁₂H₁₀S)₂], crystallize as mononuclear pseudo‐square‐planar complexes. In the cis compound, the Pt—Cl distances are 2.295 (2) and 2.319 (2) Å, and the Pt—S distances are 2.280 (2) and 2.283 (2) Å. In the trans compound, Pt is located on a centre of inversion and the Pt—Cl and Pt—S distances are 2.2786 (15) and 2.3002 (12) Å, respectively.     

A 1,2,4‐diazaphospholane complex of rhodium

The crystal structure of a prospective olefin catalyst, namely {2‐[1‐acetyl‐5‐(2‐hydroxy­phenyl)‐4‐phenyl‐1,2,4‐di­aza­phospholan‐3‐yl]­phenyl acetate‐κP}chloro­(η⁴‐cyclo­octa‐1,5‐diene)rhodium(I) di­chloro­methane solvate, [RhCl(C₈H₁₂)(C₂₄H₂₃N₂O₄P)]·CH₂Cl₂, has been determined at 173 K. The five‐membered heterocycle of the phosphine ligand is in a slightly distorted twist conformation. An intramolecular N1—H1⃛Cl1 hydrogen bond contributes to the adopted conformation and may additionally participate in secondary interactions with substrates during catalysis.     

The chloro­(diethyl­amino)­di­methyl­tin dimer

The title compound, di‐μ‐diethyl­amido‐N:N‐bis­[chloro­di­methyl­tin(IV)], consists of discrete [Sn₂Cl₂(CH₃)₄(C₄H₁₀N)₂] dimer mol­ecules, with Sn atoms linked by bridging diethyl­amido groups. The coordination geometry about the metal atom is distorted trigonal bipyramidal, with the two methyl C atoms and one N atom in the equatorial plane, and the Cl and second N atom in axial positions.     

Tetrameric di­chloro­(tri­methyl­ammonio‐p‐toluene­sulfonamidate)­mercury(II)

In the title compound, hexa‐μ‐chloro‐di­chloro­tetrakis(N‐tri­methyl­ammonio‐p‐toluene­sulfonamidate‐κ²N,O)­tetramer­cury(II), [Hg{Me₃N(+)N(−)SO₂C₆H₄CH₃‐p}Cl₂]₄ or [Hg₄Cl₈(C₁₀H₁₆N₂O₂S)₄], four nearly linear and parallel Cl—Hg—Cl units associate through pairwise Hg⋯Cl interactions of 3.1–3.2 Å. Each Hg atom is also coordinated through N and O atoms to a yl­ide mol­ecule. The available structural data indicate that coordination of a sulfonyl‐stabilized nitro­gen yl­ide to a metal atom (Hg or Ag) has no detectable effect on its geometry.     

Bis­[1‐(p‐chloro­phenyl)‐5‐iso­propyl­biguanide‐κ2N2,N4]­nickel(II) dichloride di­methyl­form­amide solvate

The asymmetric unit of the title compound, [Ni(C₁₁H₁₆ClN₅)₂]Cl₂·C₃H₇NO, contains one monomeric nickel(II) com­plex cation, two Cl⁻ anions and one di­methyl­form­amide sol­vent mol­ecule. The Ni atom is coordinated to each of two 1‐­(p‐chloro­phenyl)‐5‐iso­propyl­biguanide (proguanil) ligands via two N atoms. The complex exhibits a square‐planar coordination, with the Ni atom lying 0.021 (2) Å out of the basal plane. The crystal packing is characterized by several hydrogen bonds.     

Three monoalkoxy‐substituted nido‐platinaboranes: [(PPh3)2PtB10H11‐8‐(OCH3)], [(PPh3)2PtB10H11‐8‐{OCH(CH3)2}] and [(PPh3)2PtB10H10‐9‐{OCH(CH3)2}]

Each of the title compounds, 8‐methoxy‐7,7‐bis­(tri­phenyl­phosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane di­chloro­methane hemisolvate, [Pt(CH₁₄B₁₀O)(C₁₈H₁₅P)₂]·0.5CH₂Cl₂, (I), 8‐isopropoxy‐7,7‐bis­(tri­phenyl­phosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane di­chloro­methane solvate, [Pt(C₃H₁₈B₁₀O)(C₁₈H₁₅P)₂]·CH₂Cl₂, (II), and 9‐isopropoxy‐7,7‐bis­(tri­phenyl­phosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane di­chloro­methane solvate, [Pt(C₃H₁₈B₁₀O)(C₁₈H₁₅P)₂]·CH₂Cl₂, (III), has an 11‐vertex nido polyhedral skeleton, with the 7‐platinum centre ligating to two exo‐polyhedral PPh₃ groups and an alkoxy‐substituted polyhedral borane ligand. Compounds (II) and (III) are isomers. The Pt—B distances are in the range 2.214 (7)–2.303 (7) Å for (I), 2.178 (16)–2.326 (16) Å for (II) and 2.205 (6)–2.327 (6) Å for (III).     

Absolute configuration of (−)‐4‐(3,4‐di­chloro­phenyl)‐4‐(2‐pyridyl)­butanoic acid: essential information to determine crucial steric features of ­arpromidine‐type hist­amine H2 receptor agonists

The structural information gained from the study of the chiral building block (R)‐(?)‐4‐(3,4‐di­chloro­phenyl)‐4‐(2‐pyridyl)­butanoic acid–l ‐(?)‐ephedrine [methyl(1‐hydroxy‐1‐phenyl­prop‐2‐yl)ammon­ium 4‐(3,4‐di­chloro­phenyl)‐4‐(2‐pyrid­yl)but­an­oate], C₁₀H₁₆NO⁺·C₁₅H₁₂Cl₂NO₂^?, can be used to deduce the absolute configuration of highly potent arpromidine‐type hist­amine H₂ receptor agonists, as the chiral butanoic acid can be converted to (R)‐(?)‐3‐(3,4‐di­chloro­phenyl)‐3‐(2‐pyridyl)­propyl­amine and to the corresponding R‐configured arpromidine analogue.     

The centrosymmetric dimer of di­chloro­(tri­methyl­siloxy)­aluminium

The title mol­ecule is dimeric, i.e. di‐μ‐tri­methyl­siloxy‐bis­(di­chloro­aluminium), [Al₂Cl₄(C₃H₉Si)₂], and possesses exact crystallographic inversion symmetry. The O atoms of the tri­methyl­siloxy groups bridge the two Al atoms to form a four‐membered ring. The Si—O bond distance [1.711 (3) Å], the Al—O mean bond distance [1.806 (4) Å] and the mean Si—C bond distance [1.875 (6) Å] appear to agree well with standard data. Mean values for C—Si—C, O—Si—C, and Si—O—Al angles are 112.9 (3), 105.8 (2), and 131.8 (2)° repectively. The two ring angles O—Al—O and Al—O—Al are 84.43 (16) and 95.57 (16)°, respectively.     

Azido­[1,1′‐bis­(di­phenyl­phosphino)­ferrocene](penta­methyl­cyclo­penta­dienyl)­rhodium(III) hexa­fluoro­phosphate

In the title compound, azido‐2κN‐bis­[μ‐(1η⁵:2κP)‐di­phenyl­phosphino­cyclo­penta­dienyl][2(η⁵)‐penta­methyl­cyclo­penta­di­enyl]­iron(III)­rhodium(III) hexa­fluoro­phosphate, [{Rh(C₁₀H₁₅)(N₃)}{Fe(μ‐C₁₇H₁₄P)₂}]PF₆ or [FeRh(C₁₀H₁₅)(μ‐C₁₇H₁₄P)₂(N₃)]PF₆, the coordination sphere of Rh^III can be described as pseudo‐tetrahedral, composed of two P atoms from a 1,1′‐bis­(di­phenyl­phosphino)­ferrocene (dppf) ligand, an azido N atom and the centroid of the ring of a C₅Me₅ (Cp*) ligand. The two cyclo­penta­dienyl rings in the dppf moiety adopt an eclipsed conformation. The Rh⋯Fe distance is 4.340 (2) Å.     

trans‐Bis­(diethano­lamine)­bis­(iso­thio­cyanato)­nickel(II)

In the neutral title complex, trans‐bis(2,2′‐imino­di­ethanol‐N,O)­bis­(iso­thio­cyanato)­nickel(II), [Ni(NCS)₂(C₄H₁₁NO₂)₂], the iso­thio­cyanate ions and the di­ethanol­amine mol­ecules act as mono­dentate and bi­dentate ligands, respectively. The Ni^II ion exhibits a distorted octahedral configuration with crystallographically imposed inversion symmetry and N_NCS—Ni—N_amine and N_NCS—Ni—O_amine bond angles of 88.78 (10) and 89.44 (10)°, respectively. The Ni—N bond distances are in the range 2.069 (3)–2.096 (2) Å. The mol­ecules are linked by hydrogen bonds to form a three‐dimensional infinite lattice.