Anti-inflammatory drugs. X.

In the solid-state structure of the title compound, C₄H₁₀N⁺·C₁₄H₁₀Cl₂NO₂⁻·H₂O, the asymmetric unit contains one cation, one anion and a water mol­ecule. There is a network of hydrogen bonds which is similar to that found in the hydrated diethyl­ammonium diclofenac salt. A comparison is made of the molecular conformation of the anions in the two related structures.     

Azinyl sulfides. L.

The title compound, C₁₉H₁₃N₃S, is folded, with the central ring in a boat conformation. The folding angle between the two quinoline rings is 150.2 (1)°. The 14‐methyl substituent is in a quasi‐axial orientation with respect to the thia­zine ring. The S?N—C_methyl angle is 120.1 (1)°.     

Azole. 45.

The three title compounds, namely (Z)‐1‐(4,5‐di­nitro­imidazol‐1‐yl)‐3‐morpholinopropan‐2‐one 2,4‐di­nitro­phenyl­hydrazone, C₁₆H₁₇N₉O₉, (IV), (Z)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitro­imidazol‐1‐yl)propan‐2‐one 2,4‐di­nitro­phenyl­hydrazone, C₂₀H₂₅N₉O₈, (Va), and (E)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitro­imidazol‐1‐yl)propan‐2‐one 2,4‐di­nitro­phenylhydra­zone tetra­hydro­furan solvate, C₂₀H₂₅N₉O₈·C₄H₈O, (Vb), have been prepared and their structures determined. In (IV), the C‐4 nitro group is nearly perpendicular to the imidazole ring and the C‐4—NO₂ bond length is comparable to the value for a normal single Csp²—NO₂ bond. In (IV), (Va) and (Vb), the C‐­5 nitro group deviates insignificantly from the imidazole plane and the C‐5—NO₂ bond length is far shorter in all three compounds than C‐4—NO₂ in (IV). In consequence, the C‐4 nitro group in (IV) is easily replaced by morpholine, while the C‐5 nitro group in (IV), (Va) and (Vb) shows an extraordinary stability on treatment with the amine. The E configuration in (Vb) is stabilized by a three‐centre hydrogen bond.     

Pseudochalkogenverbindungen. XXIV. Cyanamido-trimetaphosphimate

Pseudochalcogeno Compounds. XXIV. Cyanamido Trimetaphosphimates Synthesis and properties of sodium cyanamido trimetaphosphimates Na₃[P₃(NH)₃O_6?n(NCN)_n] (n:2,4) are reported. This compounds may be obtained by cautious hydrolysis of the corresponding hydrocyanamido-chloro-trimetaphosphimates, P₃N₃Cl_6?n(NHCN)_n. For sodium trimetaphosphimate, Na₃[P₃(NH)₃O₆] a simple, modified synthetic route is described. Possibilities of the formation of pseudochalcogeno-trimetaphosphimates of the type [P₃(NH) ₃O_6?n{C(CN)₂}_n]^3? (n = 2, 4) are discussed.     

Bildung siliciumorganischer Verbindungen. LXII. Teilbromierte Carbosilane

Formation of Organosilicon Compounds. LXII. Partial Brominated Carbosilanes The photobromination of 1 leads to compound 2 as well as to C-chlorinated derivatives if the time of reaction is prolonged. Compound 2 is also formed from (Br₂Si–CH₂)₃; Gl. (1) see ?Inhaltsübersicht”?. In a corresponding reaction (Cl₃Si–CH₂)₂SiCl₂ gives successively Cl₃Si–CHBr–SiCl₂–CH₂–SiCl₃, Cl₃Si–CBr₂–SiCl₂–CH₂–SiCl₃ and Cl₃Si–CCl₂–SiCl₂–CH₂–SiCl₃. (Cl₃Si)₂CBr₂ is accessible through the photobromination of (Cl₃Si)₂CH₂. The reactivity of the CBr₂-group is quite obvious in the reaction of Cl₂Si–CBr₂–SiCl₂–CH₂–SiCl₃ with LiAlH₄ yielding (H₃Si–CH₂)₂SiCl₂ as well as in the reaction of compound 2 with CH₃MgCl yielding [(CH₃)₂Si–CH₂]₃. By treatment of the SiH groups with bromine the preparation of compounds with the general formulas CH₃SiH_nBr_3?n; (H_3?nSiBr_n)₂CH₂; (H_3?nSiBr_n? CH₂)₂SiH_2?nBr_n; (H_2?nBr_nSi? CH₂)₃ and (H_3?nSiBr_n)₂CCl₂ is possible. Analysis of the nmr spectra shows that 1,3-Dibromo-1,3,5-trisilacyclohexane is formed to 67% in the trans and to 33% in the cis configuration; 1,3,5-Tribromo-1,3,5-trisilacyclohexane is formed to 80–90% in teh cis-trans configuration. The results of ¹H and ²⁹Si NMR investigations are reported.     

Bildung siliciumorganischer Verbindungen. XXXIX. Teilchlorierte Carbosilane

1. Photochlorination in CCl₄ of the Si-chlorinated carbosilanes (Cl₃Si? CH₂)₂SiCl₂ and (Cl₂Si? CH₂)₃ leads to totally chlorinated compounds, e. g. (Cl₃Si? CCl₂)₂SiCl₂. After chlorination has started at one CH₂ group, formation of a CCl₂ group is preferred before another CH₂ group is involved into the reaction. Thus preparation of compounds a, b, c is possible. Cl₃Si? CCl₂? SiCl₂? CH₂? SiCl₃ (a) for (b) and (c) (see “Inhaltsübersicht”). SO₂Cl₂ (benzoyl peroxide) as chlorinating agent reacts more slowly, and opens an access to carbosilanes containing CHCl groups such as (d), Cl₃Si-CHCl? SiCl₂? CH₂? SiCl₃ (e). Reactions of compounds (a) to (d) with LiAlH₄ yields carbosilanes with SiH groups, and partially chlorinated C atoms. 2. By the high reactivity of Si? CCl₂? Si groups an exchange of Cl atoms of CCl groups in perchlorinated carbosilanes is possible for H atoms of Si? H groups in perhydrogenated carbosilanes, thus allowing the preparation of compounds containing CHCl and SiHCl groups, e. g. according to Gl.(1) (Inhaltsübersicht). Further reactions, formulated as the last equations in Inhaltsübersicht, are reported as well as the rearrangement of H₃Si? CHCl? SiH₃.     

Azole. 44.

The structure analyses of racemic 3‐chloro‐1‐(4‐morpholino‐5‐nitro­imidazol‐1‐yl)­propan‐2‐ol, C₁₀H₁₅ClN₄O₄, (II), and 3‐chloro‐1‐(5‐morpholino‐4‐nitro­imidazol‐1‐yl)­propan‐2‐ol, C₁₀H₁₅ClN₄O₄, (III), have been undertaken in order to determine the position of the morpholine residue in these two isomers. The morpholine residue in (II) is connected at the 4‐position, while in (III), it is connected at the 5‐position of the imidazole ring. The morpholine mean planes and nitro groups in the two compounds deviate from the imidazole planes to different extents. The nitro groups in (II) and (III) take part in the conjugation system of the imidazole rings. In consequence, the exocyclic C—N bonds are significantly shorter than the normal single Csp²—NO₂ bond and the nitro groups in (II) and (III) show an extraordinary stability on treatment with morpholine and piperidine [Gzella, Wrzeciono & Pöppel (1999). Acta Cryst. C 55 , 1562–1565]. In the crystal lattice, the mol­ecules of both compounds are linked by O—H?N and C—H?O intermolecular hydrogen bonds.     

Bildung siliciumorganischer Verbindungen. 89. Selektive Photobromierung von Si-methylierten Carbosilanen

Formation of Organosilicon Compounds. 89. Selective Photobromination of Si-methylated Carbosilanes A selective photobromination of the C atoms in the skeleton of Si-methylated carbosilanes is reported. (me₃Si? CH₂)₂Sime₂ reacts to me₃Si? CBr₂? Sime₂? CH₂? Sime₃ in good yields (me = CH₃); the second CH₂ group is considerably slower brominated. Photobromination of (me₂Si? CH₂)₃ consecutively yields a and b . Also from (me₂Si? CH₂)₄ the derivative with one CBr₂ group is accessible. Bromination of tertiary CH groups is highly preferred; this is shown by the selective formation of c . The C-bromination of SiBr-substituted carbosilanes is significantly more difficult; nevertheless (Brme₂Si)₂CH₂ selectively forms (Brme₂Si)₂CBr₂. Brme₂Si? CH₂? Sime₂? CH₂? Sime₃ forms Brme₂Si? CH₂? Sime₂? CBr₂? Sime₃, i. e., only the CH₂ group non-adjacent to SiBr is attacked. The formation of CHBr groups could not be detected. Higher temperatures and longer reaction times increase the formation of polymers.     

Synthesen in der Carotinoid-Reihe. 22. Mitteilung. Totalsynthese von Rhodoxanthin

The total synthesis of rhodoxanthin according to the scheme C₁₄ + C₁₂ + C₁₄ is reported.     

Polysulfonylamines. CXXXII.

The crystal structure of the title compound, C₅H₇N₂⁺·C₁₂H₁₀NO₄S₂⁻, consists of two independent cation–anion pairs, A and B. Within each pair, the H—N—C—N*—H grouping (N*—H is the pyridinium function) and one N—S—O moiety of the anion are linked by N*—H⃛N and N—H⃛O hydrogen bonds to form an antidromic ring motif of type R²₂(8). The remaining amino donors give rise to N—H⃛O hydrogen bonds, connecting the ion pairs into A–B–A–B– chains. The structure testifies to the persistence of the R²₂(8) motif in question, which was previously detected as a highly robust supramolecular synthon in a series of onium di(methane­sulfonyl)­amidates. The structure is pseudosymmetric; the anion positions correspond to space group P2₁/n, but those of the cations do not.     

Polysulfonylamine. VII. Aliphatische Trisulfonylamine

Polysulfonyl Amines. VII. Aliphatic Trisulfonyl Amines The compounds N(SO₂R¹)₂(SO₂R²) with R¹ = R² = CH₃ ( 2a ), R¹ = R² = C₂H₅ ( 2b ) and R¹ = CH₃, R² = C₂H₅ ( 2c ) are prepared by cleavage of aminostannanes (CH₃)₃SnN(SO₂R¹)₂ with sulfonyl chlorides R²SO₂Cl. A simple synthesis of 2a from AgN(SO₂CH₃)₂ and CH₃SO₂Cl is described. From the vibrational spectra of 2a , evidence is obtained for a planar NS₃ group in this compound. X-ray structure determinations of 2b and HN(SO₂C₂H₅)₂ ( 3 ) are reported. In 2b , the NS₃ group is approximately planar (S? N? S bond angles 119.0 ± 0.6°, sum of bond angles at N 356.9°); the S? N bond lengths of ca. 173 pm indicate a bond order of 1. In compound 3 , the nitrogen atom has a planar coordination (S? N? S angle 125.3°, sum of bond angles at N 359.3°), the S? N bond lengths of ca. 165 pm correlate with a bond order of 1.3? 1.4.     

Cyclometallated compounds. XV.

The title complex, tetra‐μ‐acetato‐O:O′‐bis{[μ‐1,4‐bis(2‐­pyridyl­oxy)­phenyl­ene‐N,C²:N′,C⁶]dipalladium(II)} bis­(tri­chloro­methane) dihydrate, [Pd₄(C₁₆H₁₀N₂O₂)₂(C₂H₃O₂)₄]·2CHCl₃·2H₂O, the product of the reaction of 1,4‐bis(2‐pyridyl­oxy)­benzene with palladium acetate, is shown to be a tetranuclear, rather than a polymeric, species. It crystallizes about a centre of inversion and has two doubly cyclo­palladated ligands bridged by four acetate groups. The cyclo­palladated ligand is far from planar in the complex and has the central benzene rings π‐stacked. The chelate rings exist in shallow boat conformations.     

Aminophosphane. XI. Einige Reaktionen des N-Diphenylphosphino-triphenyl-phosphazens

N-Diphenylphosphino-triphenylphosphazene possesses a highly reactive (C₆H₅)₂P group. At room temperature CH₃J adds to give (C₆H₅)₃P?N?P(C₆H₅)₂CH ₃J whilst phenylbromide did not react under similar conditions. The phosphorous halides (C₆H₅)₂PX(X = Cl, Br)add in a 1:1 mole ratio to yield (C₆H₅)₃P?N?P(C₆H₅)₂? PC₆H₅)₂X; this addition is also the preferred reaction with C₆H₅PCl₂, but PCl₃ is in part dehalogenated by (C₆H₅)₃P?N? P(C₆H₅)₂, and PSCl₃ desulfurized. The chalcogens O, S, Se, Te readily add to the P(III) atom of the base and this is also the case with BH₃. CS₂ forms the betaine (C₆H₅)₃ · · P?N? P(C₆H₅)₂? C(S)S. The IR and NMR spectra of the new compounds are discussed.     

Opposid,vermutliche Struktur. Glykoside und Aglykone, 302. Mitt.

The hypothetical structure 1 is proposed for opposide (C₂₉H₄₄O₁₁), a new glycoside from the seeds of Acokanthera oppositifolia (LAM.) CODD. Opposide is derived from the new aglycone gratogenin, which is most probably the 1β, 3β, 5β, 11α, 14β-pentahydroxy-card-20:22-enolide ( 8 ) (C₂₃H₃₄O₇) and which is bound glycosidically through position 3 to the α-pyranosidic form of 6-desoxy-L-talose. The hydrolysis of opposide by HCl in acetone gave an anhydrogenin (C₂₃H₃₂O₆) instead of the intact aglycone. In analogy to the reaction sequence observed by VOLPP and TAMM for ouabagenin, the structure of the anhydrogenin is deduced to be that of a 3β, 5β, 14β-trihydroxy-1α, 11α-epoxy-card-20:22-enolide ( 6 ). The above mentioned structures are based on the course of acetylation and especially on NMR.-spectra.     

Fluordiazadiphosphetidine, 16. Mitt.

The reaction of (CH₃NPF₃)₂ with NH₃ and primary aliphatic and aromatic amines in the molar ratio 3:2 yields (CH₄NPF₄)₂ and the monoamino substituted fluordiaza-diphosphetidines. These react with N-Trimethylsilyl-methylamine to the mixed diamino substituted compounds.With 1,4-Diazabicyclo[2.2.2]octan as HF-acceptor a second step of nucleophilic substitution with NH₃ and primary amines is possible. In the case of ammonia a by- product has been identified as the 1:1 adduct of (CH₃NPF₂NH₂)₂ with 1,4-diazabicyclo[2.2.2]octan.

Herrn Prof. Dr.O. Hromatka zum 80. Geburtstag gewidmet.     

Thermodynamics of plasticized triblock copolymers. I. Theory

The thermodynamic theory of bulk ABA copolymers developed by Leary and Williams is extended to copolymer–solvent systems. Free energy expressions are derived for five hypothetical phase-separated morphologies and evaluated specifically for a polymer with approximately 25% of the A component. The separation temperature, T_s, at which a given morphology will be in equilibrium with a homogeneous mixture, is also evaluated. The major result is the prediction of the T_s(?S) depression, where ?s is the solvent fraction. Depression is maximized when δ_S is equidistant between δ_A and δ_B, but becomes rapidly less when δ_S is outside the δ_A–δ_B range. Morphological favoritism is independent of ?_S and δ_S (model does not apply to preferential precipitation), with a planar microstructure being favored along with microstructures containing domains of B in continuous A for the 25% A polymer.     

Separation of dixanthogen and sulphur xanthates by H.P.L.C.: Disproportionation of Sulphur Dixanthates

High-performance liquid chromatography on C₁₃ reverse-phase or silica gel columns, with methanol—water (85:15) or n-hexane, respectively, as mobile phase, is used to separate dixanthogens and sulphur xanthates with different alkyl groups. Detection limits are as low as 1 ng (0.05 ppm) with u.v. detectors. When molecular emission cavity analysis is used for the detector, detection limits are reduced to ca. 0.25 ng (0.013 ppm). In aqueous methanol, alkyl sulphur dixanthates, (ROCS₂)₂S, disproportionate to yield mixtures of the corresponding dixanthogen, (ROCS₂)₂ , alkyl sulphur monoxanthates, (ROCS₂)₂S₂ , and dixanthates.     

Neue Verbindungen mit Granatstruktur. VI. Vanadate

New Compounds with Garnet Structure. VI. Vanadates The preparation of vanadate-garnets of the following three types is reported: (I) {Na₃}[B₂^III](V₃)O₁₂ (B^III = Cr, Sc), (II) {LiCa₂}[B₂^II](V₃)O₁₂ (B^II = Mg), (III) {Ca₂A^III}[Li₂] (V₃)O₁₂ (A^III = In, Sc). The Cr-compound of type (I) decomposes above 690°C into a mixture of Cr₂O₃ and NaVO₃. The analogous Fe-compound decomposes in a similar way already at 400°C; therefore the preparation by solid state reaction is not possible. Employing larger B^III-ions (Y, Yb, Lu) no garnets of type (I), but mixtures of B^IIIVO₄ (zircon structure) and Na₃B^IIIV₂O₈ are formed. Garnets of type (II) do not exist, when B^II are Co and Ni. Mixtures of {Ca₃}[LiB^II](V₃)O₁₂ (garnet structure), LiB^IIVO₄ (spinel structure) and B₃^II(VO₄)₂ are formed. With type (III) for A^III = Y reaction occurs forming a mixture of YVO₄, Ca₃(VO₄)₂ and Li₃VO₄.     

Anti‐inflammatory drugs. IX.

In the solid‐state structure of the title compound, C₄H₁₂N⁺·C₁₄H₁₀Cl₂NO₂^?·H₂O, the asymmetric unit contains one cation, one anion and a water mol­ecule. A complex network of hydrogen bonds is present. A comparison is made with the structure of the an­hydro­us salt.     

E.S.R. and D.S.C. investigations of phase transitions in polymorphic 4-n-alkoxybenzylidene-4′-n-alkylanilines

Abstract

It is shown that the McMillan parameter M = T _SAN/T _N1 (where T _SAN and T _NI are respectively the temperatures of the smectic A to nematic (SAN) and the nematic to isotropic (NI) phase transitions) is useful in analysing the crossover between second and first order behaviour of the S_NN transition in the nO.m homologous liquid crystal series (the 4-n-alkoxybenzylidene-4′-n-alkylanilines). Using a phase diagram of orientational ordering versus M for this series, as obtained in this work (from E.S.R. and D.S.C), a symmetric tricritical point with mean field exponent β₂ = 1 is demonstrated. In a preliminary study of E.S.R. linewidth parameters B and C of nitroxide spin probes dissolved in members of the nO.m series exhibiting a first order S_AN transition, critical-type divergences are observed near this transition. In the case where M is closer to 0.959 (the value at the tricritical point), these divergences appear similar to those previously observed in related nO.m members with a second order S_AN transition; however, they are considerably enhanced for an M value closer to unity (i.e. more removed from the tricritical point). This indicates the importance of coupling between orientational and positional order parameters in the observed critical-type divergences.