Cage‐to‐Cage Cascade Transformations

A series of Pd₂ L ₄‐type binuclear self‐assembled coordination cages ( 1 – 4 ), where L stands for a nonchelating bidentate ligand, were prepared. The strategies adopted for the synthesis of the cages were: combination of Pd^II with 1) a selected ligand or 2) subcomponents of the ligand. Highly efficient cage‐to‐cage transformation reactions are demonstrated by suitable covalent modification (from 1 to 2 or 3 or 4 ) or ligand‐exchange reactions (from 1 to 2 or 3 or 4 ; from 2 to 3 or 4 ). Thus, new cascade transformations (from 1 to 2 to 3 ; from 1 to 2 to 4 ) are achieved beautifully.     

Experimental (solid + liquid) phase equilibria of (alkan-1-ol + benzonitrile), (amine + benzonitrile) binary mixtures,and (decan-1-ol + decylamine + benzonitrile) ternary mixtures

(Solid + liquid) phase diagrams, SLE have been determined for (octan-1-ol, or nonan-1-ol, or decan-1-ol, or undecan-1-ol + benzonitrile) and for (hexylamine, or octylamine, or decylamine, or 1,3-diaminopropane + benzonitrile) using a cryometric dynamic method at atmospheric pressure. Simple eutectic systems with complete immiscibility in the solid phase and complete miscibility on the liquid phase have been observed. The solubility decreases with an increase of the number of carbon atoms in the alkan-1-ol, or amine chain. The temperature of the eutectic points increases and shifts to lower alkan-1-ol, or amine mole fractions as the alkyl chain length of the alkan-1-ol, or amine increases. The higher intermolecular interaction was observed for the (alkan-1-ol + benzonitrile) systems.     

Phase behaviour of 1-hexyloxymethyl-3-methyl-imidazolium and 1,3-dihexyloxymethyl-imidazolium based ionic liquids with alcohols,water, ketones and hydrocarbons: The effect of cation and anion on solubility

The liquid–liquid equilibrium (LLE), or solid–liquid equilibrium (SLE) of more than 20 binary systems containing 1-hexyloxymethyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)-imide [C₆H₁₃OCH₂MIM][Tf₂N] with alcohol (butan-1-ol, or hexan-1-ol, or octan-1-ol), water and ketone (3-pentanone, or cyclopentanone) and of 1-hexyloxymethyl-3-methyl-imidazolium tetrafluoroborate [C₆H₁₃OCH₂MIM][BF₄] with alcohol (methanol, or ethanol, or butan-1-ol, or hexan-1-ol, or octan-1-ol), water and ketone (3-pentanone, or cyclopentanone) have been measured. The solubility of dialkoxy-imidazolium salts: (1) 1,3-dihexyloxymethyl-imidazolium bis(trifluoromethylsulfonyl)-imide [(C₆H₁₃OCH₂)₂IM][Tf₂N] in alcohol (butan-1-ol, or hexan-1-ol, or octan-1-ol, or decan-1-ol), in water and hydrocarbon (benzene, hexane and cyclohexane); (2) 1,3-dihexyloxymethyl-imidazolium tetrafluoroborate [(C₆H₁₃OCH₂)₂IM][BF₄] in alcohol (hexan-1-ol, or octan-1-ol, or decan-1-ol) and water have been measured. Measurements were carried out by using a dynamic method from T = 275 K to the boiling point of the solvent. In this work a systematic study of the impact of different factors on the phase behaviour of hexyloxy-imidazolium-based ionic liquids with polar and nonpolar solvents has been presented. Most of the examined systems showed immiscibility in the liquid phase with an upper critical solution temperature (UCST), or complete solubility of the ionic liquid at room temperature in many solvents. An increase in the alkyl chain length of alcohol resulted in an increase in the UCST. The choice of anion was shown to have large impact on the solubility: by changing the anion [Tf₂N]⁻ to [BF₄]⁻, the solubility dramatically decreased and the UCST increased. By contrast, increasing hydrogen bonding opportunities with the solvent by replacing a methyl group with the second alkoxy-group on the imidazolium ring results in an increase of the solubility.     

Photoinduzierte 1, 3-dipolare Cycloaddition von 3-Phenyl-2H-azirinen an Azodicarbonsäure-diäthylester. 32. Mitteilung über Photoreaktionen

Irradiation of 2, 2-dimethyl-3-phenyl- ( 1a ), 2, 3-diphenyl-2H-azirine ( 1b ) or the azirine-precursors 1-azido-1-phenyl-propene ( 2a ) and 1-azido-1-phenyl-ethylene ( 2b ), respectively, in benzene in the presence of azodicarboxylic acid diethylester, yields the corresponding 1, 2-carbethoxy-3-phenyl-Δ³-1, 2, 4-triazolines 4a–d (Scheme 1). Refluxing 4 ( a, c or d ) in 0, 2–0, 4M aqueous ethanolic potassium hydroxide leads to the formation of the 1-carbethoxy-3-phenyl-Δ²-1, 2, 4-triazolines 6 ( a, c or d ). Under the same conditions 4b is converted to 3, 5-diphenyl-1, 2, 4-triazole ( 7b , Scheme 2). In 10M aqueous potassium hydroxide solution heating of either 4 ( c or d ) or 6 ( c or d ) yields the 3-phenyl-1, 2, 4-triazoles 7 ( c or d ). Photolysis of 1-carbethoxy-5, 5-dimethyl-3-phenyl-Δ²-1, 2, 4-triazoline ( 6a ) in benzene in the presence of oxygen and trifluoroacetic acid methylester gives the 5-methoxy-2, 2-dimethyl-4-phenyl-5-trifluoromethyl-3-oxazoline ( 13 , Scheme 5). 5, 5-Dimethyl-3-phenyl-1, 2, 4-triazole seems to be the intermediate, which on losing nitrogen gives the benzonitrile-isopropylide ( 3a ).     

Dihydrocytosines and cytokines from 3-aminopropionitriles

The synthesis of dihydrocytosines 4 from 3-aminopropionitriles 1 has been broadened and the dihydrocytosines themselves have now been successfully converted to cytosines 9 . Unsubstituted 3-(H, alkyl or aryl) aminopropionitriles ( 1 , X = H) convert with cyanate to 1-(H, alkyl or aryl)-1-(2-cyanoethyl)ureas ( 2 , X = H), which in turn easily cyclize with anhydrous strong acid or base to 1-(H, alkyl or aryl)-5,6-dihydrocytosines ( 4 , X = H). The 1-arylaminopropionitriles ( 1 , X = H) which are poorly reactive with cyanic acid combine readily with benzoylureas to form 3-benzoyl-1-(2-cyanoethyl)-1-arylureas ( 3 , X = H). These benzoylureas likewise cyclize with strong acid or base but with simultaneous elimination of the benzoyl moiety to yield the 1-aryldihydrocytosines 4 (X = H). Amines have successfully been added to 2-chloroacrylonitrile to yield 2-chloro-3-(amino and substituted amino)propionitriles ( 1 , X = Cl). These 2-chloropropionitriles also could be converted with cyanate or benzoylisocyanate to ureas and benzoylureas, respectively (1-(H or alkyl)-1-(2-chloro-2-cyanoethyl)ureas ( 2 , X = Cl) or 1-(H or alkyl)-1-(2-chloro-2-cyanoethyl)-3-benzoylureas ( 3 , X = Cl). The chlorine substituted ureas were unstable especially to base and to heat but with anhydrous acid were cyclized in high yield to 1-(H or alkyl)-5-chloro-5,6-dihydro-cytosines ( 4 , X = Cl). Direct chlorination of unsubstituted dihydrocytosines 4 (X = H) did not afford these same 5-chlorodihydrocytosines 4 (X = Cl) under any conditions investigated. 1-Ethyl-5,6-dihydrocytosine ( 4b ) as the cation (hydrobromide) is converted directly in good yield to 1-ethylcytosine hydrobromide ( 7 ) by bromine in nitrobenzene at 140-160° in a concomitant bromination dehydrobromination reaction. 1-(Alkyl or aryl)-5,6-dihydrocytosines ( 4 , X = H) are halogenated at low temperature in the presence of base to form (N³ or N⁴)halogenodihydrocytosines ( 8 , R = H). The N-chlorodihydrocytosines 8 are stable. The N-bromo and N-iodo compounds isomerize spontaneously to 5-halogeno-5,6-dihydrocytosines ( 4 , X = Br, I; R = H). The 5-halogeno-5,6-dihydrocytosines 4 (X = Cl, Br, I) whether from cyclization or direct halogenation are readily dehydrohalogenated to the corresponding cytosines 9.     

Synthesis and reactions of ν2-(2-formylphenyl)tetracarbonylmanganese(I) complexes; cyclopentaanulation of a diterpenoid

Reaction of tetracarbonylmangenese(I) complexes derived from a diterpenoid aryl aldehyde or aryl methyl ketone with acetylene or ethylene leads to cyclopentaannulation to give 1H-inden-1-ols or 1H-indan-ols, respectively.     

Second-sphere ligand-field effects in solid solutions of anhydrous transition-metal phosphates

Powders of the solid solutions In1-xCrxPO4 (0 < or = x < or = 1), In1-xCrx(PO3)3 (0 < or = x < or = 1), (In1-xCrx)4(P2O7)3 (0 < or = x < or = 0.7), and In1-xMnx(PO3)3 (0 < or = x < or = 0.8) have been synthesized by solid-state reactions. Depending on the dopant concentration, these materials show striking variations in color [In1-xCrxPO4, light pink to green-brown; (In1-xCrx)4(P2O7)3, light pink to red-brown; In1-xCrx(PO3)3, pale green to green; In1-xMnx(PO3)3, light blue to purple). Powder reflectance spectra of the solid solutions were measured in the UV/vis/NIR region (5500-35000 cm(-1)). Observed d-d electronic transition energies and results of calculations within the framework of the angular overlap model (AOM) for the low-symmetry chromophores [M(III)O6] (M = Cr, Mn) are in good agreement. In the case of the mixed In/Cr phosphates, the observed color changes can be related to second-sphere ligand-field effects. Clear evidence for differences in the pi-bonding of oxygen toward Cr(3+) (d(3) ion) and In(3+) (d(10) ion) are observed. For In1-xMnx(PO3)3, the variation in color is attributed to a slightly increasing elongation of the [Mn(III)O6] chromophore with increasing dopant concentration.     

The excess molar enthalpies and volumes of (N-methyl-2-pyrrolidinone + an alkan-1-ol) at T=298.15 K

The excess molar enthalpies H_m^E, for the mixtures (N-methyl-2-pyrrolidinone + ethanol, or pentan-1-ol, or hexan-1-ol, or heptan-1-ol, or octan-1-ol, or nonal-1-ol, or decan-1-ol, or undecan-1-ol) at T=298.15 K and atmospheric pressure have been obtained using flow calorimetry. Excess molar volumes at T=298.15 K and atmospheric pressure have also been determined for (N-methyl-2-pyrrolidinone + nonal-1-ol, or decan-1-ol, or undecan-1-ol) from density measurements using a vibrating tube densimeter. The experimental results have been correlated and compared with the results from the Flory–Benson–Treszczanowicz (FBT) theory and from the Extended Real Associated Solution (ERAS) model. The ERAS model accounts free volume effects according to the Flory–Patterson model and additionally association effects between the molecules involved. For the mixtures studied here the association effects arise from the self association of an alkan-1-ol molecules and also the cross-association of the proton of the alkan-1-ol with carbonyl oxygen of N-methyl-2-pyrrolidinone (NMP) molecule. The parameters adjusted to the mixtures properties are two cross-association parameters and the interaction parameter responsible for the exchange energy of the van der Waals interactions. Self-association parameters of the alcohols and NMP are taken from the literature.     

Densities,excess molar volumes,and refractive indices of ethyl acetate and aromatic hydrocarbon binary mixtures

Densities, excess molar volumes, refractive indices, and changes in refractive index on mixing for (ethyl acetate  +  benzene, or methylbenzene, or ethylbenzene, or 1-4-dimethylbenzene, or 1-methylethylbenzene, or 1-3-5-trimethylbenzene, or 1-1-dimethylethylbenzene) have been determined atT =  298.15 K. The excess molar volumes and changes in refractive index have been fitted to Redlich–Kister polynomials. The π -electrons interactions of the benzene ring and the peculiar plate shape of the aromatic molecules are noticeably modified by the presence of the ethyl acetate molecules of a different nature. The intermolecular interactions are strongly modified and result in positive excess volumes except for toluene or p -xylene whose values are close to zero. The refractive indices were compared with calculated values using mixing rules proposed by several authors.     

Reaktionen mit phosphororganischen verbindungen—XXXIV : Verhaltensweisen der sich von N-amino-aziridinen ableitenden P-N-ylide gegenüber carbonylverbindungen

The (aziridin-1-ylimino)-triphenylphosphoranes 1a and 1b react with acyl halides or -pseudohalides to form imidoyl halides or -pseudohalides some of which have considerably high stability. The reaction of 1a or 1b with several isocyanates yields the carbodiimide derivatives 6a–6f which are substituted by an aziridine ring. Addition of benzoyl bromide to 6a or 6b produces the ring-opened compounds 7 or 8.     

新型吡唑并嘧啶并吡唑三元稠合化合物的合成

Novel fused heterotricyclic compounds 3—6 containing two different dipyrazolopyrimidine framework were prepared from 1a—1d. The reaction of 1 with K2CO3 in DMSO or NaH in DMF led to the formation of 2 or 3, respectively, which reacted further to afford 6 or 5, respectively.     

Conversion of 4-amino-4H-1,2,4-triazole to 1,3-bis(1H-azol-l-yl)-2-aryl-2-propanols and 1-phenacyl-4-[(benzoyl or 4-toluenesulfonyl)-imino]-(1H-1,2,4-triazolium) Ylides

A series of 1,3-bis(1H-azol-1-yl)-2-aryl-2-propanols 17 were synthesized in an one-pot procedure by reacting l-aryl-2-(1H-1,2,4-triazol-l-yl)- or l-aryl-2-(1H-imidazol-l-yl)ethanones with dimethylsulfoxonium methide in the presence of either 1,2,4-triazole or imidazole. The aromatic groups in 17 were either 4-bromo-, 4-chloro-, 2,4-dichloro- or 2,4-difluorophenyl. 4-Amino-4H-1,2,4-triazole was acylated with either benzoyl or 4-toluene-sulfonyl chloride to afford [4-(benzoyl or 4-toluenesulfonyl)amino]4H-1,2,4-triazole. Subsequent alkylations with 4-bromo- or 4-chlorophenacyl bromide produced 1-(4-bromo- or 4-chlorophenacyl)-4-[(benzoyl- or 4-toluenesulfonyl)amino]-1H-1,2,4-triazolium bromides. Neutralizations of these salts provided the corresponding ylides.     

Donor-Acceptor Complexes in Copolymerization. XXVI. Effect of Solvent,Temperature, and Complexing Agent on the Polymerization of Comonomer Charge Transfer Complexes

The copolymerization of styrene with methyl methacrylate (S/MMA = 4/1) or acrylonitrile (S/AN = 1/1) in the presence of ethylaluminum sesquichloride (EASC) yields 1/1 copolymer in toluene or chlorobenzene. In chloroform the S-MMA-EASC polymerization yields 60/40 copolymer while the S-AN-EASC polymerization yields 1/1 copolymer. In the presence of EASC, styrene-α-chloroacrylonitrile yields 1/1 copolymer (DMF or DMSO), S-AN yields 1/1 copolymer (DMSO) or radical copolymer (DMF), S-MMA yields radical copolymer (DMF or DMSO), α-methylstyrene-AN yields radical copolymer (DMSO) or traces of copolymer (DMF), and α-MS-methacrylo-nitrile yields traces of copolymer (DMSO) or no copolymer (DMF). When zinc chloride is used as complexing agent in DMF or DMSO, none of the monomer pairs undergoes polymerization. However, radical catalyzed polymerization of isoprene-AN-ZnCl₂ in DMF yields 1/1 alternating copolymer. The copolymerization of S/MMA in the presence of EASC yields 1/1 alternating copolymer up to 100°C, while the copolymerization of S/AN deviates from 1/1 alternating copolymer above 50°C. The copolymerization of S/MMA deviates from 1/1 copolymer at MMA/EASC mole ratios above 20 while the copolymerization of S/AN deviates from 1/1 copolymer at MMA/EASC ratios above 50.     

Alkylation and cyclopentannulation of phospholene derivatives

The deprotonation of 1-phenyl-3-phospholene 1-oxide, 1-sulfide or 1-borane with 1 or 2 equiv of LDA, followed by quenching with electrophiles gave a range of 2-mono- or 2,5-disubstituted phospholene derivatives in good yield. Only trans substitution in relation to the P-Ph group was observed. Treatment of lithiated phospholene intermediates with 1,3-dihaloalkanes afforded annulated 2-phenyl-2-phosphabicyclo[3.3.0]oct-3-ene derivatives. The annulation reactions occurred with high regio- and stereoselectivity and led to the exclusive formation of the exo-Ph-P substituted products.     

Excess molar volumes and viscosities of (1,1,2,2-tetrabromoethane + 1-alkanols) at T = (293.15 and 303.15) K

Density and viscosity measurements for binary mixtures of (1,1,2,2-tetrabromoethane + 1-pentanol, or + 1-hexanol, or + 1-heptanol, or + 1-octanol, or + 1-decanol) at T = (293.15 and 303.15) K, have been conducted at atmospheric pressure. The excess molar volumes V^E, have been calculated from the experimental measurements, and the results were fitted to Redlich–Kister equation. The viscosity data were correlated with the model of Grunberg and Nissan, and McAllister four-body model. The excess molar volumes of (1,1,2,2-tetrabromoethane + 1-pentanol, or + 1-haxanol, or + 1-heptanol, or + 1-octanol) had a sigmoidal shape and the values varied from negative to positive with the increase in the molar fraction of 1,1,2,2-tetrabromoethane. The remaining binary mixture of (1,1,2,2-tetrabromoethane + 1-decanol) was positive over the entire composition range. The effects of the 1-alkanol chain length as well as the temperature on the excess molar volume have been studied. The results have been qualitatively used to explain the molecular interaction between the components of these mixtures.     

Amine-induced rearrangements of 2-bromo-1-(1H-indol-3-yl)-2-methyl-1-propanones: A new route to α-substituted indole-3-acetamides, β-substituted tryptamines, α-substituted indole-3-acetic acids and indole β-aminoketones

The reaction of 2-bromo-1-(1H-indol-3-yl)-2-methyl-1-propanone ( 1 ) and 2-bromo-1-(1-methyl-1H-indol-3-yl)-2-methyl-1-propanone ( 2 ) with primary amines proceeds in good yields to produce rearranged amides by a proposed pseudo-Favorskii mechanism. These amides in turn can either be reduced to produce β-substituted tryptamines or hydrolyzed to produce substituted indole-3-acetic acids. When the reaction is carried out using bulky primary or secondary amines, β-aminoketones are produced by elimination of hydrogen bromide followed by Michael addition. When hindered secondary amines or tertiary amines are used, elimination to the α,β-unsaturated ketones occurs.     

Stereochimie d'heterocycles du groupe IVB—II : Syntheses stereoselectives d'hydrogeno-1 et d'alkyl-1 sila-1 cyclobutanes

The reaction between n-butyllithium and 1,2 (or 1,3)-dimethyl-1-t-butoxy-1-silacyclobutanes proceeds with retention of configuration at silicon, and yields 10/90 (or 80/20) Z/E mixture of 1,2 (or 1,3)-dimethyl-1-n-butyl-1-silacyclobutanes. Methylation of 2 (or 3)-methyl-1-t-butoxy-1-silacyclobutanes (Z/E = 15/85 or 65/35) by methylmagnesium iodide gives 15/85 (or 65/35) Z/E mixture of 1,2 (or 1,3)-dimethyl-1-silacyclobutanes. The proposed configurations for substituted silacyclobutanes are supported by spectroscopic data (RMN) and chemical results (correlation of configuration and stereomutation of hydrogenosilacyclobutanes).     

Furan derivatives. Part 8 On substituent effects in the synthesis of 4,5-dihydro-3H-naphtho[1,8-bc]furans

4,5-Dihydro-3H-naphtho[1,8-bc]furans 4 and 6 which have various substituents (R¹ and R²) have been synthesized from 8-oxo-5,6,7,8-tetrahydro-1-naphthyloxyacetic acids 1 and 3 or their ethyl esters 2 . The reaction of acids 1 and 3 with sodium acetate in acetic anhydride gave a mixture of furans 4 and 6 and lactones 5 and 7 . The ratios of the products were varied according to the types of substituents (R¹ and R²) in acids 1 and 3 . As the substituent R¹ (R² = hydrogen) in acids 1 was changed from hydrogen to a methyl, ethyl or isopropyl group, production of furans 4 became more difficult. However, when a phenyl group was used as the substituent, furan 4 was obtained in good yield. Similarly, as the substituent R² (R¹ = hydrogen) in acids 1 was changed from hydrogen to a methyl, ethyl or isopropyl group, furan formation was more difficult. In contrast, acids 3 which had electron-withdrawing substituents such as chlorine, bromine or a nitro group at the 4-position afforded furans 6 in good yield. 4,5-Dihydro-3H-naphtho[1,8-bc]furans 4 and 4,5-dihydro-3H-naphtho[1,8-bc]furan-2-carbocylic acids 8 were synthesized from the reaction of esters 2 and potassium hydroxide in dioxane. When the substituents R¹ or R² in esters 2 were varied from hydrogen to a methyl, ethyl or isopropyl group the total yields of furans 4 and furancarboxylic acids 8 were reduced.     

Synthesis and Characterization of (Z)-1-[2-(Triarylstannyl)vinyl]-1-Cyclohexanols and their Arylhalostannyl Derivatives

1-Ethynyl-1-cyclohexanol reacts with a triaryltin hydride Ar₃SnH (Ar = phenyl, p-tolyl) and generates the corresponding (Z)-1-[2-(triarylstannyl)vinyl]-1-cyclohexanol. The product obtained reacts with one or two equivalents of halogen (ICl or I₂) to form the associated (Z)-1-[2-(diarylhalostannyl)-vinyl]-1-cyclohexanol or (Z)-1-[2-(aryldihalostannyl)vinyl]-1-cyclohexanol, respectively. All compounds were characterized by elemental analysis, ¹H, ¹³C, ¹¹⁹Sn NMR and Mössbauer spectroscopy.