Synthèse et polymérisation de monomères chlorofluorés allyliques vinyliques et acryliques

Synthesis, polymerization and copolymerization of allylic, vinylic and acrylic monomers containing chlorinated or chlorofluorinated substituents were studied. The reactivity of terminal alcohols or acids is influenced by their neighbouring group. By products and their mechanism of formation were studied.La synthèse et la polymérisation d'acrylates fluorés, a donné lieu à de nombreux travaux. Une première méthode d'obtention de ces composés consiste à faire réagir un alcool fluoré avec un chlorure d'acide insaturé. Les acrylates obtenus sont de la forme :

     

Triazènes. Etude XPS. et 1H-RMN. des complexes mercuriques des diaryl-1,3-triazènes

XPS. and ¹H-NMR. spectra of 1,3-diaryltriazenes complexes of Hg(II) The core binding energies C 1s, N 1s, Hg 4f_7/2, Hg 4f_5/2 in 7 symmetrical p-substituted 1,3-diphenyltriazenes complexes of Hg(II) have been measured by XPS. Within the limits of experimental error (± 0.2 eV) only one N 1s signal could be detected. This indicates the equivalence of the 3 N-atoms. Invariance of C 1s, N 1s, Hg 4f_7/2, Hg 4d_5/2 signals with the para substituents on the phenyl ring is explained on the basis of ionic character in the Hg, N bond. These results are corroborated by the ¹H-NMR. spectra.     

Aza-2-diènes-1,3. 2. Synthèse et structure d'un ylure d'azométhine stable

2-Aza-1,3-dienes. 2. Synthesis and Structure of a Stable Azomethine-ylid. Thermal treatment of 2-(2′-cyano-2′-methoxycarbonyl)methylide-amino-1-morpholino-cyclohexene results in the formation of a stable isomere. Its azomethine-ylid structure is demonstrated from the spectroscopic data (UV., IR., ¹H- and ¹³C-NMR.). 1,3-dipolar cycloaddition reactions of this ylid leads to spiropyrrolines.     

Synthèses et caractérisation de germylènes difonctionnels

Syntheses and caracterization of bifunctional germylenes Several synthetic methods of bifunctional germylenes GeY₂ (Y = RO, PhO, RS, CH₃COO, Acac; Y₂ = OCH₂CH₂O, SCH₂CH₂S) or GeXY (Y = RO, X = Cl; Y = RS, X = Cl; Y = Acac, X = Cl) such as exchange reactions, dechlorhydratation reactions and nucleophilic substitutions from GeCl₂ · dioxane are described. Some more synthesis of divalent species GeY₂ from Ge(OR)₂ by transalcoxylation and from Ge(Cp)₂ by cleavage using protic species will be presented. The stability and reactivity of these germylenes are discussed. Difunctionnal germylenes give generally a selfpolycondensation reactions. However, their reactivity in situ shows a effective participation of monomeric species GeY₂.     

Aza-2-diènes-1,3 4. Préparation et propriétés d'alkyl-1-pyrazone-imines et de leurs isomères

2-Aza-1,3-dienes. Synthesis and Properties of 1-Alkylpyrazone-imines and their Tautomers Treatment of 5-dialkylamino-1,1-dicyano-2-aza-1,3-dienes (or their 1-methoxycarbonyl analogoues) with primary amines gives substituted 1-alkyl-3-cyano-(or methoxycarbonyl-)pyrazoneimines. Tautomeric behaviour, nucleophilic addition to imino function and spectroscopic data of these isomers are examined.     

Synthèse et réactivité de dihydrotriazines et de dihydrotriazolotriazines

Generally, 4,5-dihydro-3triazinones have been prepared by a basic hydrolysis of 3-methylmercapto-4,5-dihydrotriazines. Of the serveral methylation methods, namely, diazomethane, methyliodide, dimethyl sulfate all in the presence of sodium methylate or silver carbonate, only methyl bromide in the presence of phase transfer catalyst was sucessful in producing all of the N-2 and/or N-4 methylate compounds. Two unequivocal syntheses of dihydrotriazolo[4,3-b]triazine are reported.     

Polymérisation radicalaire du pentadiène-1,3. II. Microstructure des résidus pentadiéniques dans les homo- et copolymères des cis et trans pentadiènes-1,3 avec l'acrylonitrile

The microstructure of diene units was investigated in radical homopolymers of the cis and trans isomers of 1,3-pentadiene and copolymers with acrylonitrile, synthetized in bulk and emulsion. Experiments were carried out by infrared spectroscopy, 100 MHz ¹H-NMR, and 25 MHz ¹³C-NMR studies. No difference between the bulk and emulsion samples was noted. The microstructure of poly(1,3-pentadiene) is practically independent of the cis or trans configuration of the diene monomer and is as follows: 56–59% trans-1,4, 15–17% cis-1,4, 16–20% trans-1,2 7–10% cis-1,2 and 0% 3,4. On the other hand, up to about 30% of incorporated acrylonitrile (10% in the feed), the microstructure of the pentadiene fraction in the copolymers is not affected. This finding suggests that the penultimate unit has very little influence on the polymerization process involving the terminal pentadienly unit. Beyond 10% of acrylonitrile in the feed, the proportions of the structural units were linearly dependent upon the acrylonitrile content: trans-1,4 content increased whereas the amounts of cis-1,4 trans-1,2 and cis-1,2 decreased (except the cis-1,2 fraction, constant in the copolymers from the cis-diene). These results are discussed on the assumption that the microstructure of pentadiene residues is strongly associated with the acrylonitrile comonomer in the feed.     

Synthèse de sucres aminès ramifiés II. Synthèse et réactions de spiro-aziridines. Communication préliminaire

Treatment of 3-C-cyano-1,2:5,6-di-O-isopropylidene-3-O-(toluene-p-sulfonyl)-α-D -allofurannose with AlLiH₄ or RMgX yields spiro-aziridines with two identical substituents on C(3′) (? H, ? CH₃, ? C₂H₅). Reactions of these products and their derivatives are briefly described. If the C(3′) substituents are protons, the aziridine ring is easily opened. In acidic media (HCl), an amino-sugar containing the branched chain ? CH₂Cl is produced; with hydrogenation, a ? CH₃ branched chain results. If the C(3′) substituents are methyl groups, the aziridine ring cannot be opened neither with HCl nor with hydrogen. The acetylated derivative of this latter compound rearranges to the corresponding allylamide with HCl. For both types of spiro-aziridine, the nitrous deamination leads to the corresponding alkene.     

Synthèse et transformations de pyridopyrimidopyrimidines

A convenient one-step synthesis of a pyridoprimidopyrimidine system by means of the chloride of 1,3-dimethy1-4amino-5-amino-5-(N,N-dimethyliminiumchloromethine)uracil and substituted pyridines is studied and the title compounds are described.     

Polymérisation anionique des diènes. VI. Microstructure des polybutadiène et polyisoprène par résonance magnétique protonique à 250 MHz et mécanismes de propagation

Analysis by 250-MHz proton magnetic resonance (PMR) allows more precise examination of the microstructure of anionic polyisoprenes and polybutadienes obtained in the presence of organo-alkali metals. Besides vinyl addition, the propagation of contact ion pairs in dioxane solvent gives a mixture of cis and trans products with isoprene, whereas only trans product is obtained with butadiene. The presence of 1,4-trans-polyisoprene appears to be inconsistent with the cis configuration of the polyisoprenyllithium living end in dioxane or tetrahydrofurane media. In taking into account the existence of complexation phenomena, it was suggested that propagation mechanisms should involve a transition state which should begin with the trans configuration before isomerization into the more stable cis configuration. For the free ions, the living end of the carbanion should be entirely trans.     

Synthèses de 3-silyl et de 3-germyl 1-sila et 1-germacyclopent-3-ènes

The synthesis of allylic sila (and germa) cyclopentenes containing an Et₃M (M = Si, Ge) group in vinylic position is described. 1-Germacyclopent-3-enes 3-silylated (IIIa) and 3-germylated (IIIb) result from 1,4-cycloaddition of GeI₂ to the corresponding 2-metallated 1,3-dienes (II). 3-Metallated 1-silacyclopent-3-enes (IIIc–IIIf) are obtained by two methods. One involves the reaction of dienes II with Me₂SiCl₂ and Mg, leading to compounds IIIc (M = Si) and IIId (M = Ge). The other method corresponds to the trichlorosilylation (HSiCl₃, Et₃N, ε Cu₂Cl₂) of dichlorinated compounds I resulting from cis-addition of Et₃MH to cis-1,4-dichlorobutyne. From the two trichlorosilylated derivatives IV and V, formed in S_N2 and S_N2′ reactions, only the 1-trichlorosilyl 2-triethylsilyl (and germyl) 4-chlorobut-2-enes (IV) give, in the presence of magnesium, the 1,1-dichloro 3-triethylsilyl (and germyl) 1-silacyclopent-3-enes (IIIe and IIIf).

Abstract

Nous décrivons la synthèse de sila (et germa) cyclopentènes allyliques (III) renfermant le groupe Et₃M (M = Si, Ge) en position vinylique. Les 1-germacyclopent-3-ènes 3-silylés (IIIa) et 3-germylés (IIIb) sont obtenus par réaction de cycloaddition-1,4 de GeI₂ sur les diènes 2-métallés (II) correspondants. Les 1-silacyclopent-3-ènes métallés (IIIc–IIIf) sont préparés selon deux méthodes. L'une, mettant en jeu les diènes II et le couple Me₂SiCl₂ Mg, conduit aux cycles IIIc (M = Si) et IIId (M = Ge). L'autre méthode consiste à effectuer la réaction de trichlorosilylation (HSiCl₃, Et₃N, ε Cu₂Cl₂) des dérivés dichlorés I qui résultent de la cis-addition de Et₃MH au cis-1,4-dichlorobutyne. Des deux dérivés trichlorosilylés IV et V formés à l'issue des réactions S_N2 et S_N2′, seuls les 1-trichlorosilyl 2-triéthylsilyl (et germyl) 4-chlorobut-2-ènes (IV) conduisent, après cyclisation par le magnésium, aux 1,1-dichloro-3-triéthylsilyl (et germyl) 1-silacyclopent-3-enes (IIIe et IIIf).     

CRYPTATES XIX. Ligands polyaza-polyoxa-macrobicycliques: Synthèse et complexes métalliques

Polyaza-polyoxa macrobicyclic ligands: its synthesis and metal complexes. The synthesis of the polyaza-polyoxa macrobicyclic ligands 1–4 is described. They form complexes with a variety of metal cations, transition metal cations as well as alkali and alkaline-earth cations. These complexes may be formulated as cation inclusion complexes, cryptates, in which the cation is contained in the intramolecular cavity. The properties of the complexes are described. An especially interesting feature is that these ligands, polymines of macrobicyclic topology, provide a means of trapping transition metal cations inside a molecular cavity; thus they impose coordination geometries and may modify the spectral and redox properties of the cations.     

Transformation,par 1′anhydride acètique,d'aldèhydes à caractére èlectrophile prononcè; catalyse par des pyridines. 1. Acyloïnes et hydrates di-o-acètylès d'aldèhydes

2-Benzothiazole-carbaldehyde is transformed into di-O-acetyl-enol-(benzothiazolecarboxyl-2)-oin in the presence of acetic anhydride and of pyridine as catalyst. Without pyridine or with 2,6-lutidine no reaction occurs. A mechanism of this reaction is proposed. No reaction was observed in the case of benzaldehyde. Choral reacts with acetic anhydride in the presence of pyridine as well as of 2,6-lutidine as catalyst to give 1,1-diacetoxy-2,2,2-trichloro-ethane. A mechanism is proposed, in which in an intermediate state the acetate ion (and not pyridine, for steric reasons) attacks the carbon of the carbonyl function of the conjugate acid with the acetylium cation to yield 1,1-diacetoxy-2,2,2-trichloro-ethane. These two reactions occur only with aldehydes whose carbonyl is very electrophilic, and seem to be a possible way to point out the presence of an acylium cation in pyridine medium.     

Polymérisation anionique des diènes. III. Etude thermodynamique de la propagation du butadiène et de i'isoprène par les organo-alcalins

The present work is concerned with the influence of the polymerization temperature on the propagation mechanisms of polyisoprenyl- and polybutadienyl-alkali metals. The thermodynamic parameters of the contact ion pairs and free ions propagations have been calculated. With Li⁺ in dioxane solvent, the vinyl propagation is stereospecific (for isoprene, the propagation is mainly 4–3). In comparison with benzene, the vinyl propagation of the polydienyl-Li contact ions pairs should be due to complexation of Li⁺ by dioxane, an electron donor having a weak dielectric constant. In general, the stereospecificity of the propagation of contact ion pairs decreases with increasing counterion size; little difference has been observed with K⁺ and Cs⁺ ion pairs in dioxane and benzene media. For isoprene, the methyl substituant should have chiefly a steric effect in the propagation of free ions, whereas it should confer a polar character to the isoprene molecule in the presence of ions pairs.     

Synthèse et tautoméric d'amino-3 et d'hydroxy-3 buténolide

The synthesis fo 3-amino- and 3-hydroxy-2-methyl-4,4-spiro-cyclohexane-2-butene-4-olide was achieved starting from isocyanate or an isocyanate precursor. The study and discussion of tautomeric structures were peformed using ir and nmr spectra functional groups reactivity.     

Chimie et pharmacologie de l'apiose III. Synthèse et propriétés de l'hydrate de l'O-isopropylidène-1, 2-tétrosulo-3-furannose

Ruthenium tetroxide oxidation of 1, 2-O-isopropylidene-β-D -threofuranose affords, besides the known 1, 2-O-isopropylidene-α-L -glycero-tetros-3-ulofuranose, a lactone. The tetrosulose is easily hydrated to the corresponding gem-diol whose dehydration on molecular sieves leads to a branched-chain dimer. Lead tetraacetate oxidation of 1, 2-O-isopropylidene-α-L -glycero-tetros-3-ulofuranose p-nitrophenylhydrazone leads quantitatively, to a gem-azoacetate, a new synthetic intermediate in carbohydrate chemistry. The 3-O-acetyl-1, 2-O-isopropylidene-α-L -glycero-tetr-3-enofuranose is easily obtained from the gem-diol. A highly stereoselective procedure is described to prepare the 3-O-acetyl-1, 2-O-isopropylidene-α-L -3, 4-exo-D₂-erythrofuranose.