Syntheses of N-substituted carbazoles involving polymerizable terminal vinyl groups

Eleven N-substituted carbazoles (CZ) with terminal vinyl groups were synthesized by five sequences of reaction: N-(p-vinylbenzyl)- and N-β-(vinyloxyethyl)CZ by N-alkylations of potassium CZ with corresponding chlorides; N-(β-acryloyloxyethyl)CZ by the esterification of N-(β-hydroxyethyl)CZ with acryloyl chloride; N-acrylamido-or methacryl-amido-methyl CZ from N-hydroxymethyl CZ and acryl- or methacrylamide; N-(3-acryloyl- or methacryloyl-oxy-2-hydroxypropyl)CZ and N-[3-(p- or m-vinylanilino)-2-hydroxypropyl] CZ from N-(2,3-epoxypropyl)CZ and acrylic or methacrylic acid and p- or m-vinylaniline, respectively; and 2-[β-(N-carbazyl)propionyloxy]ethyl acrylate or methacrylate by the Michael addition of CZ to 2-hydroxyethyl acrylate or methacrylate, followed by esterifications. The vinyl polymers with pendant carbazyl groups more or less distant from the polymer backbones, prepared by conventional radical or cationic polymerization procedures, indicated charge-transfer spectra with 2,4,7-trinitrofluorenone (TNF) in tetrahydrofuran (THF) solutions that are spread over most of the visible range.     

GROUP 13 CLUSTER CHEMISTRY: ORGANOGALLIUM AND -INDIUM SUBHALIDES AND RADICALS

Organogallium or-indium subhalides are easily available by the halogenation of the corresponding tetrahedral clusters E ₄ [C(SiMe ₃ ) ₃ ] ₄ . Three types of compounds are formed that retain the tetrahedral arrangement of In atoms or give chains with two or three Ga or In atoms connected by E─E bonds. These subhalides are suitable starting compounds for the synthesis of secondary products containing the elements in low oxidation states. Carboxylato derivatives or transition metal complexes were obtained on such a route. A persistent radical anion was formed on electron transfer to Ga ₉ (CMe ₃ ) ₉ .     

Experimental Study of the Excess Molar Enthalpy of Ternary Mixtures Containing Water + (1,2-Propanediol, or 1,3-Propanediol, or 1,2-Butanediol, or 1,3-Butanediol, or 1,4-Butanediol, or 2,3-Butanediol)+Electrolytes at 298.15 K and Atmospheric Pressure

Excess molar enthalpies (H _m ^E) of ternary mixtures containing water+(1,2-propanediol or 1,3-propanediol or 1,2-butanediol or 1,3-butanediol or 1,4-butanediol or 2,3-butanediol)+(sodium bromide, or ammonium bromide, or tetraethyl ammonium bromide, or 1-n-butyl-3-methylimidazolium bromide at 0.1 mol⋅dm⁻³) at 298.15 K and atmospheric pressure have been determined as a function of composition using a modified 1455 Parr mixture calorimeter. The H _m ^E values are negative for all mixtures over the whole composition range. The influence of the electrolyte on the hydrophobic and hydrophilic effects as well as on the behavior of H _m ^E is discussed.     

Syntheses,spectroscopy, and catalysis of (η 4-cod)Rh(I)-complexes with (R or S)-2-(salicylaldimine)-2-phenylethanol or (rac)-2-(salicylaldimine)-1-phenylethanol

Condensation of salicyldehyde with (R or S)-2-amino-2-phenylethanol or rac-2-amino-1-phenylethanol gives enantiopure (R or S)-2-(salicylaldimine)-2-phenylethanol (R- or S-H₂L1) or (rac)-2-(salicylaldimine)-1-phenylethanol (rac-H₂L2). The Schiff bases coordinate to [Rh(η ⁴-cod)(μ-O₂CCH₃)]₂ to afford mononuclear [Rh(η ⁴-cod){(R or S)-2-(salicylaldiminato)-2-phenylethanol-κ ² N,O}], [Rh(η ⁴-cod)(R- or S-HL1)] (1 or 2), or [Rh(η ⁴-cod){(rac)-2-(salicylaldiminato)-1-phenylethanol-κ ² N,O}], [Rh(η ⁴-cod)(rac-HL2)] (3). The Schiff base and complexes are characterized by IR-, UV/Vis-, ¹H/¹³C-NMR-, mass-spectroscopy, circular dichroism (CD), and polarimetry. The synthetic and spectroscopic results suggest that deprotonated Schiff base coordinates to [Rh(η ⁴-cod)] as a six-membered N,O-chelate with distorted square planar geometry at rhodium. CD and polarimetry measurements show the enantiopurity of the Schiff bases as well as the complexes in solution. The in situ system composed of [Rh(η ⁴-cod)Cl]₂ and S-H₂L1 has been used as a catalyst for the reduction of acetophenone into rac-1-phenylethanol with 85% conversion in diphenylsilane at 0–5°C.     

Stereoselectivity in Reactions of Metal Complexes. Part XV. Structure and stability of chiral cobalt(III) complexes with pentadentate ligands

The syntheses and characterization of four new linear pentadentate ligands and their Co^III complexes are described: N,N′-[(pyridine-2,6-diy)bis(methylene)]bis[sarcosine] (sarmp), N,N′-[(pyridine-2,6-diyl)bis(methylene)]bis[(R)- or (S)-proline] ((R,R)- or (S,S)-promp), N,N′-[(pyridine-2,6-diyl)bis(methylene)]bis[N-(methyl)-(R)- or (S)-alanine] ((R,R)- or (S,S)-malmp); 2,2′-[pyridine-2,6-diyl]bis[(S)- or rac-N-(acetic acid)pyrrolidine] ((S,S)- or rac-bapap). The complexes were characterized and, with but one exception, complex formation is stereospecific: Δ-exo-(R,R) (or Λ-exo-(S,S)) for promp and Λ-(R,R) (or Δ-(S,S)) for bapap. The exception is [Co((R,R)- or (S,S)-malmp)H₂O]ClO₄ for which two forms are obtained, to which Λ-endo-(R,R) (or Δ-endo-(S,S)) and, tentatively, Δ-unsymmetric-(R,R)- (or Λ-unsymmetric-(S,S)-) configurations are assigned. X-Ray crystal structures are presented for the complexes [Co(sarmp)H₂O]ClO₄, [Co((S,S)-promp)H₂O]ClO₄, [Co(rac-bapap)H₂O]ClO₄ and endo-[Co(rac-malmp)H₂O]ClO₄. Ligand acid dissociation and Co^II and Fe^II complex-formation constants are reported.     

Isentropic Compressibility Changes of Mixing for 1,3-Dioxolane or 1,4-Dioxane + Water + Propanol Ternary Mixtures

Speed of sound data, u_ijk, of 1,3-dioxolane or 1,4-dioxane(i) + water(j) + propan-1-ol or propan-2-ol(k) ternary mixtures and their sub-binary mixtures, u_ij, of 1,3-dioxolane or 1,4-dioxane(i) + water or propan-1-ol or propan-2-ol(j) and water(i) + propan-1-ol or propan-2-ol(j) mixtures have been measured over the entire composition range at 308.15 K. Isentropic compressibility changes of mixing, (κ_s^E)_ij and (κ_s^E) _ijk, for the binary and ternary mixtures have been determined by employing the observed speeds of sound data and densities (calculated from their molar excess volumes data). The (κ_s^E) _ij and (κ_s^E) _ijk values have also been predicated by the graph theoretical approach and the Flory theory. It has been observed that (κ_s^E) _ij and (κ_s^E) _ijk predicted by the graph theoretical approach compare well with their corresponding experimental values.     

α-单取代环十二酮肟及缩氨基硫脲的合成及晶体结构

单晶X射线衍射分析表明, α-单取代环十二酮与氨衍生物羟胺和氨基硫脲发生缩合反应得到两种母体构象均为[3333], 而取代基为边外向或角反向的α-单取代环十二酮肟或缩氨基硫脲. 利用底物的“角位羰基参与反应”原理, “记忆效应”及进攻试剂与底物是否形成氢键解释了这一实验结果. 通常情况下, 试剂从空间障碍小的一面进攻羰基而生成α-角反取代环十二酮肟或缩氨基硫脲. 当试剂与底物的取代基之间能够形成分子间氢键时, 则生成α-边外取代环十二酮肟或缩氨基硫脲.     

The Formalism of Titration Theory

Acid—base theory can be rationalized by introducing the concept of the proton function, ^HC. Specifically, the pH of any solution is given by ^HC = 0, the buffer strength is given by B = [H⁺]d^HC/d[H⁺], and the titration of any acid or mixture of acids with a base or mixture of bases (or its inverse) is given by ^HC_t V_t = -^HC₈V₈, where t and s denote titrant and sample respectively. The same unifying approach can be extended to complexation, precipitation, and redox equilibria.     

Syntheses,Structures, and Catalytic Reactions of Palladium Adducts of Chiral Diphosphines That Contain a Rhenium Stereocenter in the Backbone

Reactions of the title diphosphines [(η⁵‐C₅H₄PPh₂)Re(NO)(PPh₃)((CH₂)_nPPh₂)] (n=0, (R)‐ 1 ; n=1, racemic or (S)‐ 2 ) with [PdCl₂(PhCN)₂] give the palladium/rhenium chelate complexes [(η⁵‐C₅H₄PPh₂)Re(NO)(PPh₃)((μ‐CH₂)_nPPh₂)PdCl₂] (n=0, (S)‐ 5 ; n=1, racemic or (S)‐ 6 ) in 75–92% yield. The crystal structure of racemic 6 shows a twisted‐boat conformation of the chelate ring, giving a chiral pocket very different from that in a related rhodium chelate. However, NOE experiments suggest a similar ensemble of conformations in solution. Catalysts are generated from various combinations of a) Pd(OAc)₂ and (R)‐ 1 or (S)‐ 2 (1 : 2), b) (S)‐ 5 or (S)‐ 6 and (R)‐ 1 or (S)‐ 2 (1 : 2), or c) (i‐Bu)₂AlH with the preceding recipes. These factors effect the Heck arylation of 2,3‐dihydrofuran with phenyl trifluoromethylsulfonate. In contrast to analogous reactions with (R)‐binap (=(R)‐2,2′‐bis(diphenylphosphanyl)‐1,1′‐binaphthalene), the major product 2‐phenyl‐2,3‐dihydrofuran is nearly racemic (≤12% ee).     

Synthesis of 5H-imidazo[5,1-a]isoindole: Photocyclization of N,N′ -bis(o-chlorobenzyl)imidazolium chloride and N-(o-chlorobenzyl)imidazole

A N-heterocyclic compound containing two hetero atoms, imidazo[5,1-a]isoindole, was synthesized in 40% yield by the intramolecular photocyclization of N,N'-bis(o-chlorobenzyl)imidazolium salts 1 in water (neutral or pH ～4) or of N-(o-chlorobenzyl)imidazole 2 , in aqueous acid (pH ?4). However, the photocyclized compound 3 was not formed effectively in basic aqueous solution (3 equivalents of sodium hydroxide or pyridine) or in acetonitrile by the photochemical reaction of N,N'-bis(o-chlorobenzyl)imidazolium salts 1 or N-(o-chlorobenzyl)imidazole (2).     

The Stereochemical Outcomes – the Isoborneol/Borneol Ratios – in Lithium,Sodium and Potassium/Ammonia Reductions without a Proton Source of the Enantiomers and the Racemate of Camphor Differ Strongly

The stereochemical outcomes [ratios (1 R, 2 R, 4 R)-isoborneol/(l R, 2 S, 4 R) isborneol or (1R, 2 S, 4 S)-isoborneol(l S, 2 R, 4 S)-borneol and (1 RS, 2 RS, 4 RS)-isoborneol/(l RS, 2 SR, 4 RS)-borneol] in lithium, sodium and potassium/ammonia reductions without a proton source of the enantiomeric [(1 R, 4 R) or (1 S, 4 S)] and racemic (1RS, 4RS) forms of camphor under the same conditions differ strongly. This explains contradictory reports in the literature and, in the case of the reductions with potassium in which pinacol coupling does not compete, proves that the reductions involve bimolecular reactions between two ketyls, or between the ketone and the ketyl or the ketone dianion.     

Etude Stéréochimique par RMN 1H de Tetrahydropyrannes β-Chlorés α-Substitués

The ¹H NMR study of 2-alkyl-3-chlorotetrahydropyrans, obtained by reaction of Grignard reagents with a mixture of cis/trans-2,3-dichlorotetrahydropyrans, shows cis/trans configuration of two isomers in which the alkyl substituents are exclusively in the equatorial position. 3-Chloro-2-phenyltetrahydropyran exists in trans (eq-eq) configuration only. The ¹H NMR study of cis/trans 2-alkoxy (or aryloxy)-3-chlorotetrahydropyrans, obtained by reaction of alcohols or phenol with 2,3-dichlorotetrahydropyrans, shows the axial position of the alkoxy (or aryloxy) substituent.     

Synthesis of porphyrinyl-nucleosides

Several porphyrinyl-nucleosides were prepared in the reaction of the OH group of one, two or four meso-p-hydroxyphenyl substituents of porphyrin with 5′-O-tosylates of 2′,3′-O-isopropylidene-adenosine or -uridine, or 5′-O-tosylthymidine; the remaining porphyrin meso-substituents were p-tolyl, p-hydroxyphenyl or 4-pyridyl. The following porphyrinyl-nucleosides were obtained with 8–17% yield: meso-di(p-tolyl)di(p-phenylene-5′-O-2′,3′-O-isopropylidene-adenosine) (or -uridine)porphyrins 1,2 , the respective meso-tetranucleosideporphyrins 3,4 -meso-mono(p-phenylene-5′-O-thymidine)porphyrins 5–7 , meso-di(p-tolyl)di(p-phenylene-5′-O-thymidine)porphyrins 8,9 and the meso-di(p-hydroxyphenyl)di(p-phenylene-5′-O-thymidine)porphyrins 10. Other compounds prepared belonged to the series: meso(4-pyridyl)_4?n(p-phenylene-5′-O-2′,3′-O-isopropylideneuridine)_nporphyrin, n = 1, 2 or 4, 11–13. N-Methylation gave the water soluble iodide salts: (N-methyl-4-pyridinium)4_4?n(p-phenylene-5′-O-2′,3′-isopropylideneuridine)_nporphyrins, n = 1, 2 or 4, 14–16. The ms fab showed in most cases stepwise detachment of the CH₂(5′)-nucleoside fragments. The porphyrins meso disubstituted by thymidine represent a convenient substrate for the build-up of both nucleoside units into the oligo/polynucleotide chains.     

一种经(E)-α-碘代烯基砜的钯催化交叉偶联反应立体选择合成(1Z,3E)-2-芳砜基取代的1,3-二烯的新方法

（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd（PPh3）4 catalyst to afford stereoselectively （1Z,3E）-2- phenyl（or p-tolyl）sulfonyl-substituted 1,3-dienes 3 in good yields.     

Design,synthesis and structure determination of new inherently chiral para-bromoalkoxycalix[4]arenes

The preparative method for the synthesis of inherently chiral para-bromoalkoxycalix[4]arenes based on para-bromination, stepwise regioselective debenzoylation and the following alkylation of the readily available 25-propoxy-26,27-dibenzoyloxycalix[4]arene with propyl bromide or (R)-N-(1-phenylethyl)bromoacetamide has been developed. Three types of the inherently chiral calix[4]arenes in cone or partial cone conformations with asymmetrical (_AHHH^HBHH, _AAHH^HBHH, _AHBH^HCHH) substitution of both upper and lower rims have been obtained in racemic, diastereomerically pure or enantiomerically pure forms. Their structure and the absolute configuration have been determined by NMR and X-ray.     

Effect of Temperature on the Volumetric Properties of [Difurylmethane+(C<Subscript>2</Subscript>–C<Subscript>6</Subscript>) Alkan-1-ol] Binary Systems: Analyses of New and Literature Density Data in the Temperature Range 288.15–308.15 K

Densities, ρ, of the binary systems {difurylmethane + (ethanol or propan-1-ol or butan-1-ol or pentan-1-ol or hexan-1-ol)} have been measured with an Anton Paar DMA 4500 vibrating-tube densimeter over the entire composition range at 288.15 and 308.15 K and atmospheric pressure. The measured and literature densities of [difurylmethane + n-alkanol] binary systems have been used to check the validity of the relationship describing the dependence of density on composition. This relation is useful for obtaining interpolated ρ values corresponding to the experimental data. Excess molar volumes (V _m^E) of each mixture, limiting (V _m,i ^E,∞) and excess partial (V _m,i ^E) molar volumes and the limiting partial molar expansion (E _p,i ^∞) of both components of each binary system have been examined to provide insight into the temperature variations of the intermolecular interactions and molecular packing efficiencies. The results have been discussed in terms of specific intermolecular interactions and structural effects.     

A convenient route for the synthesis of s,s-and R,R-warfarin alcohols

S,S-and R,R-warfarin alcohols 3 are prepared in good yield and in 99% d.e. (diastereomeric excess) by the reaction of S- or R-warfarin 1 with S or R-Alpine-Hidride 2.     

Volumetric Properties of (Difurylmethane + Alkan-1-ol) Binary Mixtures at 298.15 K

Densities (ρ)of the binary systems of {difurylmethane + (ethanol or propan-1-ol or butan-1-ol or pentan-1-ol or hexan-1-ol)} have been measured with an Anton Paar DMA 4500 vibrating-tube densimeter over the entire composition range at 298.15,K and atmospheric pressure. Excess molar volumes (V _m ^E ) of each binary system were determined and correlated by the Redlich-Kister equation. Limiting (V _i ^E,∞) and excess partial molar volumes (V _i ^E ) of components of each binary system have been calculated to provide insight into the intermolecular interactions present and the packing efficiencies. The results have been discussed in terms of specific intermolecular interactions, dispersive forces and structural effects.     

Alkylation of Imidazolidinone Dipeptide Derivatives: Preparation of Enantiomerically Pure Di- and Tripeptides by ‘Chirality Transfer’ via a Pivalaldehyde N,N-Acetal Center. Preliminary Communication

Glycylglycine, glycyl-(S)-alanine, and (S)-alanylglycine esters are cyclized through pivalaldehyde imines to give dipeptide-derived 3-(benzyloxycarbonyl)-2-(tert-butyl)-5-oxoimidazolidine-1-acetates 1 – 3 . These are alkylated diastereoselectively by Li-enolate formation and addition of alkyl bromides or iodides (products 4 – 6 ). Starting from (S)-alanine and glycine, (S)-alanyl-(S)-alanine or (R)-alanyl-(R)-alanine, and (R)-alanyl-(R)alanyl-(S)-alanine- have thus been prepared, with the (tert-butyl)-substituted N,N-acetal center playing the role of a pivot or lever for diastereoselective formation of new stereogenic centers under kinetic or thermodynamic control.