Cone and 1,3‐alternate conformers of 1,3‐bis­(ethoxy­carbonyl­methoxy)‐2,4‐di­hydroxy­calix­[4]­arene and 1,2,3,4‐tetrakis­(ethoxy­carbonyl­methoxy)­calix­[4]­arene

The two title ethoxy­carbonyl­methoxy derivatives of calix­[4]­arene, namely diethyl 2,4‐di­hydroxy­calix­[4]­arene‐1,3‐diyldi(oxy­ace­tate), C₃₆H₃₆O₈, (I), and tetraethyl ­calix­[4]­arene‐1,2,3,4‐tetra­yltetra­(oxy­acetate), C₄₄H₄₈O₁₂, (II), form two different conformations, viz. a cone in (I), where intramol­ecular hydrogen bonds are formed through OH groups in a partially substituted calix­[4]­arene, and a 1,3‐alternate form of a completely substituted calix­[4]­arene in (II). A unique three‐dimensional array of mol­ecules exists in (II), with the channels extended along the entire crystal.     

5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrakis(2‐cyano­benzyl­oxy)‐2,8,14,20‐tetra­thia­calix­[4]­arene–di­chloro­methane (1/2)

A new p‐tert‐butyl­thia­calix­[4]­arene derivative, C₇₂H₆₈N₄O₄S₄·2CH₂Cl₂, has been synthesized and is comprised of one tetra‐p‐tert‐butyltetrakis(2‐cyano­benzyl­oxy)­tetra­thia­calix­[4]arene and two di­chloro­methane mol­ecules. The calix­[4]­arene mol­ecule is centrosymmetric and adopts an unusual 1,2‐alternate conformation viaπ–π interactions between adjacent cyano­phenyl rings on the lower rim of the parent thia­calix­[4]­arene system.     

25,27‐(6‐Tosyl‐3,9‐dioxa‐6‐aza­un­decane‐1,11‐diyldioxy)‐26,28‐(3,6,9‐trioxaun­decane‐1,11‐diyldioxy)­calix­[4]­arene

A new calix­[4]‐­crowned aza­crown ether, C₅₁H₅₉NO₁₁S, consisting of four phenyl rings in a 1,3‐alternate conformation was synthesized from the reaction of 25,27‐bis(5‐chloro‐3‐oxa­pentyl­oxy)­calix­[4]­crown‐5 and p‐toluene­sulfon­amide in the presence of Cs₂CO₃. A crown‐5 loop was attached on the two facing lower rims of the calix­[4]­arene and the N‐tosyl aza­crown group was attached on the other set of lower rims of the calix­[4]­arene backbone. This mol­ecule seems to offer an inside cavity for the formation of a host–guest complex.     

(5,11,17,23‐Tetra‐tert‐butyl‐26,28‐di­hydroxy­calix­[4]­arene‐25,27‐dioxy)­di­acetic acid N,N‐di­methyl­form­amide trisolvate

The title compound, C₄₈H₆₀O₈·3C₃H₇NO, is a derivative of calix­[4]­arene in the cone conformation, modified with distal carboxylic acid functional groups at the lower rim. A clathrate di­methyl­form­amide (DMF) mol­ecule is located within the calix­[4]­arene cone, and two DMF solvate mol­ecules participate in hydrogen bonding with the carboxylic acid groups. Intramolecular hydrogen bonds are also formed between the OH groups and the adjacent ether groups in the partially substituted calix­[4]­arene.     

2,4‐Di­hydroxy‐1,3‐bis­(methoxy­carbonyl­methoxy)­calix­[4]­arene and 1,3‐bis­(ethoxy­carbonyl­methoxy)‐2,4‐di­hydroxy­calix­[4]­arene chloro­form solvate

The two title calix­[4]­arene compounds, C₃₄H₃₂O₈, (I), and C₃₆H₃₆O₈·CH₃Cl, (II), respectively, which differ only in the size of the alkyl function on the pendant ester group, are compared. Compound (I) forms a novel supramolecular array, whilst (II) fails to do so due to accommodating a chloro­form guest molecule in the lower‐rim cavity.     

A uranyl ion complex of N‐methyl‐p‐tert‐butyl­dihomo­ammonio­calix­[4]­arene with di­aqua­di­pyridine­lithium as counter‐ion

The title complex, di­aqua­di­pyridine­lithium (N‐methyl‐p‐tert‐butyl­dihomo­ammonio­calix­[4]­arene‐κ⁴O)­dioxouranium(VI) tri­pyridine solvate monohydrate, [Li(C₅H₅N)₂(H₂O)₂][UO₂(C₄₆H₅₈NO₄)]·3C₅H₅N·H₂O, contains an `internal' tetraphenoxide‐coordinated uranyl complex of the macrocycle, in which the protonated N atom is involved in an intramolecular hydrogen bond with the uranyl oxo group located in the cavity. The Li⁺ ion is in a tetrahedral environment and its two water ligands are involved in hydrogen bonds with two phenoxide O atoms, two pyridine mol­ecules and one water mol­ecule. This arrangement is compared with those obtained previously for other homo­aza­calixarenes and also for homo­oxa­calixarenes in the presence of alkali metal hydro­xides.     

1,3‐Bridged p‐methyloctahomotetraoxacalix[4]arene–bis‐crown‐3

The title compound, 13,21,35,43‐tetra­methyl‐3,6,9,17,25,28,31,39,46,49‐decaoxahepta­cyclo­[21.21.3.3^11,33.0^2,41.0^10,15.0^19,24.0^32,37]pentaconta‐1,10,12,14,19,21,23,32,34,36,41,43‐dodecaene, C₄₄H₅₂O₁₀, differs from previously reported 1,3‐bridged calix­[4]­arene–bis‐crown compounds in having an enlarged calixarene ring and shorter polyoxy­ethyl­ene bridges. The cavity is partly filled by the bridges.     

Intermolecular stacking in pyrazolo[3,4‐d]pyrimidine‐based pentamethylene‐linked flexible ­molecules

The crystal structures of 1‐{5‐[4,6‐bis­(methyl­sulfanyl)‐2H‐py­razolo­[3,4‐d]­pyrimidin‐2‐yl]­pentyl}‐6‐methyl­sulfanyl‐4‐(pyr­rolidin‐1‐yl)‐1H‐pyrazolo­[3,4‐d]­pyrimidine, C₂₂H₂₉N₉S₃, and 6‐methyl­sulfanyl‐1‐{5‐[6‐methyl­sulfanyl‐4‐(pyrrolidin‐1‐yl)‐2H‐pyrazolo­[3,4‐d]­pyrimidin‐2‐yl]­pentyl}‐4‐(pyrrolidin‐1‐yl)‐1H‐pyrazolo­[3,4‐d]­pyrimidine, C₂₅H₃₄N₁₀S₂, which differ in having either a pyrrolidine substituent or a methylsulfanyl group, show intermolecular stacking due to aromatic π–π interactions between the pyrazolo­[3,4‐d]­pyrimidine rings.     

Disappearance of intramolecular stacking due to one‐atom movement or increment of a `propyl­ene linker' in pyrazolo­[3,4‐d]­pyrimidine‐based ­flexible models

In the crystal structures of 4,6‐di­methyl­thio‐1‐[3‐(4,6‐di­methyl­thio‐2H‐pyra­zolo­[3,4‐d]­py­rimi­din‐2‐yl)­propyl]‐1H‐py­ra­­zolo­[3,4‐d]­py­rimi­dine, C₁₇H₂₀N₈S₄, and 1‐[4‐(4‐meth­oxy‐6‐methyl­thio‐1H‐pyra­zolo­[3,4‐d]py­rimi­din‐1‐yl)­butyl]‐5‐meth­yl‐6‐methyl­thio‐4,5‐di­hydro‐1H‐pyra­zolo­[3,4‐d]py­rimi­din‐4‐one, C₁₈H₂₂N₈O₂S₂, only intermolecular stacking due to aromatic π–π interactions between pyrazolo­[3,4‐d]­pyrimidinerings is present.     

A dimeric layered structure of a 4‐oxo‐4,5‐di­hydro‐1H‐pyrazolo­[3,4‐d]­pyrimidine compound

The title compound, 6‐methyl­sulfanyl‐1‐(3‐phenyl­propyl)‐4,5‐di­hydro‐1H‐pyrazolo­[3,4‐d]­pyrimidin‐4‐one, C₁₅H₁₆N₄OS, crystallizes in space group Pbca, with two mol­ecules of similar structure in the asymmetric unit. The molecular structure shows the absence of intramolecular stacking in the crystalline state, as indicated by earlier ¹H NMR analysis in solution. In addition, the crystal packing reveals the formation of a layered structure, due mainly to intermolecular N—H?O=C hydrogen bonding and arene–arene interactions.     

Ethyl N‐[2‐(hydroxy­acetyl)­phenyl]­carbamate,ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]­carbamate and ethyl N‐[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]­carbamate

In ethyl N‐[2‐(hydroxy­acetyl)phenyl]carbamate, C₁₁H₁₃NO₄, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the mol­ecules are linked into simple chains by a single C—H⋯O hydrogen bond. The mol­ecules of ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]carbamate, C₁₁H₁₂INO₄, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐­[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]carbamate, C₁₂H₁₅NO₄, crystallizes with Z′ = 2 in the space group P; pairs of mol­ecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking inter­actions.     

4,4′‐Bis(4‐iodo­phenyl­amino­methyl)­azoxy­benzene: hydrogen‐bonded sheets built from C—H⃛O and C—H⃛π(arene) hydrogen bonds

Borohydride reduction of N‐(4‐nitro­benzyl­idene)‐4‐iodo­aniline has yielded the title compound, 1,2‐bis­[4‐(4‐iodo­phenyl­amino­methyl)­phenyl]­diazene 1‐oxide, C₂₆H₂₂I₂N₄O. The mol­ecules lie across centres of inversion in P2₁/c, with the azoxy O atom disordered over two sites, each having an occupancy of 0.5. The mol­ecules are linked into sheets by a combination of C—H⃛O and C—H⃛π(arene) hydrogen bonds.     

Chiral and meso‐bis([2.2]­para­cyclo­phan‐4‐yl)­methane and meso‐bis­([2.2]­para­cyclo­phan‐4‐yl) sulfide

The [2.2]­para­cyclo­phane groups of the title compounds, chiral and meso‐bis­(tri­cyclo­[8.2.2.2^4,7]­hexa­deca‐4,6,10,12,13,15‐hexa­en‐5‐yl)­methane (the former as a racemate), C₃₃H₃₂, and meso‐bis­(tri­cyclo­[8.2.2.2^4,7]­hexa­deca‐4,6,10,12,13,15‐hexa­en‐5‐yl) sulfide, C₃₂H₃₀S, show the characteristic structural features of the parent compound [2.2]­para­cyclo­phane and the related compound di­methylbis([2.2]­para­cyclo­phan‐4‐yl)­silane, C₃₄­H₃₆­Si: the aromatic rings are puckered, resulting in a boat conformation. The planes of the four coplanar C atoms are slightly twisted with respect to each other. The Csp³—Csp³ bond lengths of the ethyl­ene bridges are elongated by the electronic and steric effects of the skeleton.     

Tris­[2‐(benzoyl­amino)­ethyl]­amine

Tris­[2‐(benzoyl­amino)­ethyl]­amine [alternatively, N,N′,N′′‐(nitrilo­tri­ethyl)­tri­benz­amide], C₂₇H₃₀N₄O₃, adopts a folded structure, forming a symmetrical cavity with an average depth of 7.3 Å and width ranging from 4.1–4.4 Å. The folded structure is a result of one intramolecular N—H?O hydrogen bond. A linear chain motif along the c axis best describes the extended intermolecular N—H?O hydrogen bonding.     

Hydro­gen bonds and C—H⋯O ­interactions in the enol tautomer of 4‐­(phenylsulfonyl)spiro­[cyclo­pentane‐1,9′‐[9H]­fluorene]‐2,3‐dione

The title compound, 2‐hydroxy‐1‐(phenyl­sulfonyl)­spiro­[cyclo­pentene‐4,9′‐[9H]­fluoren]‐3‐one, C₂₃H₁₆O₄S, crystallized in the centrosymmetric space group P2₁/n with one mol­ecule as the asymmetric unit. The hydroxyl‐H atom is ordered and participates in a single intramolecular hydrogen bond and in a single intermolecular hydrogen bond, in which the O_D—H distance is 0.90 (2), H?O_A is 2.34 (3), O_D?O_A is 2.987 (2) Å and O_D—H?O_A is 129 (2)°. The intermolecular hydrogen bond forms an R(12) cyclic dimer about a center of symmetry. There are six leading C—H?O interactions. Taken together, these interactions form a three‐dimensional network. Structural comparisons are made with tetrabenzodi­spiro­[4.0.4.3]­tridecatetraene.     

Di­spiro­[fluorene‐9,5′‐[1,2,3,4]­tetra­thia­ne‐6′,9′′‐fluorene]

The tetra­thia­ne ring of the title compound, C₂₆H₁₆S₄, has a chair conformation and the mol­ecule has approximate C₂ symmetry. Each of the two fluorene ring systems is virtually planar, with the ring planes intersecting at an angle of 67.58 (5)°. This novel compound has been formed as a side product from the treatment of 9H‐fluorene‐9‐thione with methyl N‐[(benzyl­idene)­phenyl]­glycinate in the presence of LiBr and 1,6‐di­aza­bi­cyclo­[5.4.0]­un­decane.     

Two isomers of 2,4‐di­benzyl‐8‐azabicyclo­[3.2.1]­octan‐3‐ol

The crystal structures of the title compounds, 2α,4α‐di­benzyl‐3α‐tropanol (2α,4α‐di­benzyl‐8‐methyl‐8‐aza­bi­cyclo­[3.2.1]­octan‐3α‐ol), C₂₂H₂₇NO, (I), and 2α,4α‐di­benzyl‐3β‐tropanol (2α,4α‐di­benzyl‐8‐methyl‐8‐aza­bi­cyclo­[3.2.1]­octan‐3β‐ol), C₂₂H₂₇NO, (II), show that both compounds have a piperidine ring in a chair conformation and a pyrrolidine ring in an envelope conformation. Isomer (I) is asymmetric, the benzyl groups having different orientations, whereas isomer (II) is mirror symmetric, and the N and O atoms, the C atom attached to the hydroxy group, and the methyl C atom attached to the N atom lie on the mirror plane. In the crystal structures of both (I) and (II), the mol­ecules are linked together by intermolecular O—H⋯N hydrogen bonds to form chains that run parallel to the a direction in (I) and parallel to b in (II).     

7‐Oxobi­cyclo­[2.2.1]­heptane‐1‐carboxylic acid and ()‐7‐oxobi­cyclo­[2.2.1]­hept‐5‐ene‐2‐endo‐carboxylic acid: hydrogen bonding in two norbornyl keto acids

Molecules of the title β‐keto acid, 7‐oxobi­cyclo­[2.2.1]­heptane‐1‐carboxylic acid, C₈H₁₀O₃, exhibit chirality due to the bridgehead carboxyl group, which is partially ordered and has a slightly asymmetric conformation. The mol­ecules form centrosymmetric hydrogen‐bonded carboxyl dimers [O?O 2.639 (2) Å]. The title alkenoic γ‐keto acid, ()‐7‐oxobi­cyclo­[2.2.1]­hept‐5‐ene‐2‐endo‐carboxylic acid, C₈H₈O₃, also forms typical centrosymmetric hydrogen‐bonded carboxyl dimers [O?O 2.660 (3) Å]. There is partial disorder of the carboxyl group in each compound.     

Supramolecular hydrogen‐bonded hexamers in two 5‐aryl‐3‐methyl‐1‐phenyl‐1,6,7,8‐tetra­hydro­pyrazolo­[3,4‐b][1,4]­diazepines

In both title compounds, i.e. 3‐methyl‐1,5‐di­phenyl‐1,6,7,8‐tetra­hydro­pyrazolo­[3,4‐b][1,4]­diazepine, C₁₉H₁₈N₄, (I), and 5‐(4‐chloro­phenyl)‐3‐methyl‐1‐phenyl‐1,6,7,8‐tetra­hydro­pyra­zolo­[3,4‐b][1,4]­diazepine, C₁₉H₁₇ClN₄, (II), an N—H?N hydrogen bond links six mol­ecules to form an R(30) ring. Compound (I) crystallizes in the R space group and (II) crystallizes in P with three mol­ecules in the asymmetric unit. The mol­ecule of (I) contains a disordered seven‐membered ring.     

3,6‐Di­chloro‐4‐[2‐(4‐thia­morpholino)­ethanesulfanyl]­pyridazine and 3,6‐bis­(pyrazol‐1‐yl)‐4‐[2‐(4‐thia­mor­pho­lino)­ethanesulfanyl]­pyridazine

The trans–trans conformations adopted by the derivatized bis­(bidentate) chelating N₄‐donor ligand 3,6‐bis­(pyrazol‐1‐yl)‐4‐[2‐(4‐thia­morpholino)­ethanesulfanyl]­pyridazine, C₁₆H₁₉N₇S₂, and an intermediate in its formation, 3,6‐di­chloro‐4‐[2‐(4‐thia­morpholino)­ethanesulfanyl]­pyridazine, C₁₀H₁₃Cl₂N₃S₂, con­trast with the cis–cis conformation found previously for 3,6‐bis­(thio­phen‐2‐yl)­pyridazine [Ackers, Blake, Hill & Hubberstey (2002). Acta Cryst. C 58 , o640–o641], which places all four heteroatoms on the same side of the mol­ecule.