Crystallization of chiral compounds. 2. Propranolol: free base and hydrochloride

The data from IR spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis are compared for crystalline specimens of homochiral and racemic propranolol and its hydrochloride. The stabilities of the racemates were quantitatively characterized and the factors responsible for the order of their stability are revealed.     

Crystallization of chiral compounds 3. 3-phenoxypropane-1,2-diol and 3-(2-halophenoxy)propane-1,2-diols

Specific features of melting of crystalline samples of 3-(2-R-phenoxy)propane-1,2-diols with different enantiomeric compositions were studied by differential scanning calorimetry. The melting points and enthalpies of melting for the racemate and individual stereoisomers were determined. Binary phase diagrams were constructed. The entropy of mixing of individual enantiomers in the liquid phase and the free energy of formation of the racemic compound were calculated. The thermochemical data indicate that the racemates are formed upon the crystallization of phenoxy-and 2-fluorophenoxy-containing compounds, while crystallization of the chloro-, bromo-, and iodo-substituted analogs would form racemic conglomerates. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 225—232, February, 2006.     

Stereochemistry of 1,3-diheterocyclanes 4. Molecular and crystal structures of monosubstituted five-membered cyclic sulfites

Racemic and enantiopure cis-and trans-4-(1-naphthyloxy)methyl-2-oxo-1,3,2-dioxathiolanes were studied by X-ray diffraction. The factors responsible for their crystal packings were revealed. The conformation of the exocyclic fragment varies from synclinal to antiperiplanar depending on both the local (cis-trans isomerism of the molecule) and external (homochiral/heterochiral environment) stereochemical factors. Data on the structures of five-membered sulfites in crystals were generalized. It was concluded that the heterocycle has considerable conformational flexibility. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1095–1102, July, 2006.     

Thermal and Spectroscopy Investigation of Cyclopalladated Compounds of the Type [Pd(C13H10N)(μ-X)]2, (X=H3CCOO,NCO, SCN,CN)

The dimeric compound [Pd(bzan)(μ-OOCCH₃)]₂ (1) (bzan=N-benzylideneaniline) reacts with KX, in methanol/acetone (2:1), affording the analogous dimeric pseudohalogen-bridged species [Pd(bzan)(μ-X)]₂ [X=NCO(2),SCN(3), CN(4)]. The compounds were characterized by elemental analysis, infrared spectroscopy, NMR and thermogravimetric analysis. IR data for 2–4 showed bands typical of coordinated pseudohalogen ligands clearly indicating the occurrence of the exchange reaction. Their thermal behaviour was investigated and suggested that their stability is influenced by the bridging ligand. The thermal stability decreased in the order[Pd(bzan)(μ-CN)]₂>[Pd(bzan)(μ-SCN)]₂>[Pd(bzan)(μ-OOCCH₃)]₂>[Pd(bzan)(μ-NCO)]₂. X-ray results showed the formation of Pd° as final decomposition product. This revised version was published online in July 2006 with corrections to the Cover Date.     

Transition metal complexes of N-1-tosylcytosine and N-1-mesylcytosine

The syntheses as well as chemical and X-ray structural characterization of dichlorobis[1-(p-toluenesulfonyl)cytosine]copper(II) (2), its solvated pseudopolymorph containing two methanol molecules (3), dichlorobis[1-(p-toluenesulfonyl)cytosine]cadmium(II) (4), 1-methanesulfonylcytosine (6) and its copper complex dichlorobis(1-methanesulfonylcytosine)copper(II) (7) are described. In addition, spectroscopic studies of dichlorobis[1-(p-toluenesulfonyl)cytosine]cobalt(II) (5), as well as of dichlorobis(1-mesylcytosine)cadmium(II) (8) are presented. Pseudopolymorphs 2 and 3, as well as their 1-mesylcytosine analog 7, reveal square-planar coordination spheres, almost ideal in the case of 2, but considerably distorted in the case of 3 and 7. In all cases, the Cu(II) ion is coordinated by two endocyclic N3 atoms from two ligand molecules and by two chlorine atoms. The analogous coordination sphere was found in complex 4, where Cd(II) lies in the center of a slightly distorted tetrahedron formed by two endocyclic N3 atoms and by two chlorine atoms.     

P,O-Ligands. Complexes of tetraphenylmethylenediphosphine oxide with silver nitrate

The 1 : 1 and 1 : 2 complexes of AgNO₃ with Ph₂PCH₂P(O)Ph₂ were prepared and their structures were established by IR and ³¹P NMR spectroscopy and X-ray diffraction analysis. The crystal of the 1 : 1 complex consists of centrosymmetric dimers based on the ten-membered macrocycle AgOPCH₂PAgOPCH₂P. Each neutral ligand serves as a bridge between two silver ions, the latter being coordinated by the NO₃ group in the monodentate fashion. In the 1 : 2 complex, the dimeric structure is retained, but both NO₃ groups are replaced by the ligand molecules.     

Structural,Vibrational, Thermal,and Electrochemical Studies of a Cyclohexaphosphate Complex, (C5H14N2)2Cd2CL2P6O18.4H2O

Abstract

A novel cadmium cyclohexaphosphate (C₅H₁₄N₂)₂Cd₂Cl₂P₆O₁₈.4H₂O has been prepared and characterized by single-crystal X-ray diffraction, infrared and Raman spectroscopies, thermogravimetric analysis, and cyclic voltammetry. The structure consists of vertex linked of CdO₅Cl octahedral and P₆O₁₈ rings assembled into a two-dimensional macroanionic layers. Organic double-protonated homopiperazine cations are located between these layers and interact with the framework both electrostatically and via hydrogen bonds of N–H···O(Cl).

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures]     

Reactivity of 2-cyano-1,4,5,6-tetrahydro-1-pyridinecarboxylic acid esters towards various nucleophiles: Regio- and stereoselectivity of the attack

Summary The synthesis and reactivity of the title compounds towards nucleophiles are discussed. The regio- and diastereoselectivity of the attack is highly dependent on the carbamic ester and the type of nucleophile applied. BothMichael type addition across the activated double bond and S_N2T reaction at the carbamate carbon atom were observed. Structure assignment of the adducts in solution and in the solid state was performed utilizing high temperature NMR techniques as well as single crystal X-ray diffraction.

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Reaktivität von 2-Cyano-1,4,5,6-tetrahydro-1-pyridincarbonsäureestern gegenüber verschiedenen Nucleophilen: Regio- und Diastereoselektivität des Angriffs

Zusammenfassung Die Synthese und Reaktivität der Titelverbindungen gegenüber Nucleophilen wird diskutiert. Die Regio- und Diastereoselektivität des Angriffs hängt stark vom jeweiligen Carbaminsäureester und vom Nucleophil ab. SowohlMichael-Addition an die aktivierte Doppelbindung als auch S_N2T-Reaktion am Carbamatkohlenstoff wurden beobachtet. Die Strukturaufklärung der Addukte in Lösung und im Festkörper wurde mit Hilfe von Hochtemperatur-NMR-Techniken sowie Einkristallröntgenbeugung durchgeführt.

     

Spectroscopic,Magnetic and Thermal Investigations on Cu(II), Mn(II), Co(II) and Fe(III) Complexes with Glutamyl Nitroanilide

New complexes CuL₂×2H₂O, CoL₂×3H₂O, MnL₂×2H₂O and FeL₃×2H₂O, L=γ-L -glutamyl-5-(p-nitroanilide), were synthesized and characterized by their spectral, magnetic and thermal properties. The thermal stabilities of the synthesized complexes were examined in the temperature range 20–500°C. In all these complexes γ-L -glutamyl-5-(p -nitroanilide) acts as a bidentate ligand, its coordination involving the carbonyl oxygen and the nitrogen atom of the second amino group. The local structure around the Cu(II) ion is pseudotetrahedral. In the Co(II), Mn(II) and Fe(III) complexes, the metal ions are in the high-spin form, with octahedral stereochemistry. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis,structure, and configuration of new spirooxyndol compound

Structure of a new spirooxyndol compound, [indoline-3,2′(3′H)-[3′-acetyl-2′-acetamide-[1,3,4]-thiodiazoline]-1-benzyl]-2, has been determined by X-ray diffraction analysis. Crystal is monoclinic, unit cell parameters are: a = 12.097(1) Å, b = 10.172(1) Å, c = 32.987(1) Å; β = 97.731(3)°, space group P2₁/n, Z = 4, compound C₄₂H₄₄N₈O₇S₂. Independent part of the unit cell is formed by two crystallographically independent molecules, practically equal in composition and configuration. Two independent molecules are united by the exosphere molecule of ethanol. Phenyl and pyrol rings are located virtually in one plane, dihedral angle formed by mean-square planes of these rings vary within 1.5(2)–3.3(2)°. In both molecules thiodiazoline and pyrol rings are spiro-joint over carbon atom, the dihedral angle formed by the latter is 89.1(1)° and 88.5(1)°, sulfur and nitrogen atoms in the molecules A and B being on different sides of pyrol ring keeping identical configuration of carbon node. Crystal structure is composed due to branched system of intermolecular hydrogen bonds.     

New N-nitrosoamines. 1. Synthesis and nitrosative cleavage of the Mannich bases derived from nitrogen-containing heterocycles and primary aliphatic amines

The reactions of isatin, benzotriazole, and succinimide with formaldehyde and methylamine yield monoamines RCH₂N(Me)CH₂R and methylenediamines RCH₂N(Me)CH₂N(Me)CH₂R. The use of ethylenediamine as the amino component affords N,N"-disubstituted imidazolidines, while the reactions with 3-aminopropan-1-ol give N-substituted tetrahydro-1,3-oxazines. RCH₂NBuⁱ ₂ was obtained from succinimide, formaldehyde, and diisobutylamine. Nitrosative cleavage of the amines obtained was studied; it was shown that monoamines and methylenediamines give N-nitrosoamines RCH₂N(NO)Me, which were structurally characterized by X-ray diffraction analysis. RCH₂NBuⁱ ₂ affords diisobutylnitrosamine, while imidazolidines transform into dinitroso compounds RCH₂N(NO)CH₂CH₂N(NO)CH₂R.     

Synthesis, spectrophotometry, and X-ray diffraction studies of a new salt: p-xylylenebis(tetrahydrothiophenium) bis(triiodide)

A new salt, p-xylylenebis(tetrahydrothiophenium) bis(triiodide) C₁₆H₂₄I₆S₂, was prepared. The molecular structure of the salt was studied by X-ray diffraction; the factors that form the crystal packing represented by...Ct...I₃...I₃...Ct... type chains (Ct is cation) were identified. The stability of p-xylylenebis(tetrahydrothiophenium) diiodochlorides and triiodides was estimated by spectrophotometry using the average iodine number function . Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1341–1344, July, 2007.     

The thermal transition behavior of poly(bis(p-flourophenoxy)phosphazene)

The thermal transition behavior of poly(bis(p-fluorophenoxy)phosphazene) was studied as a representative aryloxy-substituted poly(organophosphazene) using X-ray diffraction, differential thermal analysis and density measurements. The crystal structure of-form contained in as-cast film had marked paracrystalline disorder. The crystal phase transformed into the mesophase atT(1) (110 140 °C). The structure of the-form observed in the mesophase was a representative hexagonal-packing of macromolecular chains which rotate around the chain axes. When the mesophase was cooled to room temperature, a more ordered crystal phase of the-form could appear. The most ordered crystal structure of the-form has a monoclinic unit cell with the following lattice parameters: a=18.9, b=13.2, c=4.90 Å, and=77°. The chain conformation is nearly planar cis-trans, which has been observed commonly in poly(organophosphazenes). The macroscopic deformation of the film sample was also examined, taking into account the microscopic deformation of the lamellar crystal due to the crystal-mesophase transition.     

Synthesis of bis-cyclopentadienyl compounds with a 9,9-fluorenylidene bridge. Crystal and molecular structure of [μ-9,9-Flu(η5-Cp)2]ZrCl2

An efficient synthetic approach to 9,9-bis(cyclopentadienyl)fluorenes was developed. The two correspondingansa-zirconocenes were synthesized. The structure of one of these compounds was established by X-ray diffraction analysis. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1290–1294, July, 2000.     

Reaction of hydroxyiminoacetophenone withp-toluenesulfonyl chloride and an X-ray diffraction study of the reaction product

2-Benzoyloxy-2-phenylmalononitrile is formed instead of the expected oxime tosylate in the reaction of hydroxyiminoacetophenone withp-toluenesulfonyl chloride. The structure of the product was confirmed unambiguously by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 872–874, April, 1997.     

Copper(II) Complexes of Spirohydantoins. Synthesis,Quantum-Chemical,and Spectroscopic Study

A series of new Cu(II) complexes with important physiologically active cycloalkane-5-spirohydantoines are synthesized reacting as a result of CuCl₂ · 2H₂O interaction with the ligands in alkaline water medium. Their structures were studied using spectroscopic (IR and EPR) methods. For comparison, ab initio calculations of the structure and IR spectra of the corresponding Cu(II) complexes were also performed. It was proven that with cyclopentane-5-spirohydantoins, distorted (flattened) tetrahedral structure is realized Cu(L_–H)₂(H₂O)₂, while with the higher cycloalkane-5-spirohydantoins linear Cu(II) complexes of the type CuL_–H(OH) are formed.     

Molecular inclusion in functionalized macrocycles. Part 12. Crystal and molecular structure of ap-(1,1,3,3)-tetramethylbutylcalix[8]arene octapodand

The title compound was obtained as colourless transparent prismatic crystals (from acetone/methanol 1:1), space groupPa=16.647(2),b=16.447(2),c=14.269(3) Å, =108.56(3), =105.63(3), =87.23(3)°,Z=1,D _calc=1.03 g cm^–3. Refinement was carried out using 2863 reflections, withI>(I). The molecule, which lies on a center of symmetry, possesses a roughly ellipsoidal shape with two sets of four phenolic nuclei following a helical arrangement. The polyether chains of two adjacent phenolic units partially fill the intramolecular cavity. No guest molecules are present. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication SUP 82025 (22 pages).For part 11 see [1].     

Crystal and molecular structure of <Emphasis Type="Italic">tris</Emphasis>(<Emphasis Type="Italic">m</Emphasis>-chlorophenyl)phosphine selenide

The crystal and molecular structure of tris(m-chlorophenyl)phosphine selenide, C₁₈H₁₂Cl₃PSe (I), was investigated by X-ray diffraction (XRD) analysis. The trigonal rhombohedral structure of I (space group \(R\overline 3 c\), a = 14.110(2) Å, c = 32.360(4) Å, Z = 12) was solved by direct methods and refined by least squares in an anisotropic approximation (R = 0.029) for 1319 averaged measured reflections (CAD-4 automatic diffractometer, λCuK_α).     

Clathrate and Inclusion Compounds. Part 13 [1]. Vibrational and NMR Spectroscopic Studies of Carboxylic Acid Guests in Urea

Infrared, Raman and solid state¹³C NMR spectra have been recorded for arange of inclusion compounds of urea containingstraight chain aliphatic carboxylic acids(butyric – decanoic) as guests. Inclusioncompounds are not formed with formic, acetic andpropionic acids. Thiourea does not forminclusion compounds with any of the C1 to C10acids. The vibrational and NMR data support theconclusion that the acids are present ashydrogen bonded dimers in the channels of thehost. The alkyl chain ¹³C chemical shiftvalues are very different from those of acidguests in the cavities formed in Dianin'scompound. These suggest that the alkyl chainsare present in the all-trans conformation,although weak bands observed in the spectrum ofthe decanoic acid inclusion compound lend somesupport to suggestions based on MM calculationsthat other conformations might be present.