Biotransformation of pinenes XVII. Transformation of α-and β-pinenes by means of Armillariella mellea (honey fungus), a parasite of woodlands

A culture of Armillariella mellea species was adapted to carry out microbial transformations of (+), (-), and (±)-α-pinene and (-)-β-pinene . The composition of products obtained indicated that allylic hydroxylation of all substrates was the most characteristic reaction for Armillariella mellea species. The hydroxylation occurred either directly in unchanged pinane skeleton yielding among other compounds verbenol ( ) and verbenone ( ) or was preceded by a cleavage of four-membered rings in substrates to form a menthane skeleton. The latter reaction leads to allylic alcohols and diols, mainly trans-sobrerol ( ) and 7-hydroxy-α-terpineol ( ).     

Synthesis and immunological properties of an artificial antigen with the repeating oligosaccharide unit of Salmonella illinois as haptenic group

The serological specificity of Salmonellae (O-specificity) is mediated by oligosaccharide subunits (repeating units) of the species-specific cell wall polysaccharides. With S. illinois (O-specificities 3, 15 and 34 of the Kauffmann-White scheme) as a representative example, it was possible to achieve the coupling of a complete repeating unit of that kind (in the case of S. illinois a tetrasaccharide) to protein, thus converting it into an artificial antigen. The repeating tetrasaccharide of the O-specific S. illinois polysaccharide has been obtained by partial acid hydrolysis of the O-specific S. illinois lipopolysaccharide and has the following structure with rhamnose as the reducing terminal sugar: In a reaction of this tetrasaccharide (TS_ill) with o-phenylenediamine and m-nitrophenylhydrazine and its subsequent reduction, TS_ill-_illl-(3-amino-phenyl)-flavazole was prepared, which was then coupled to edestin by means of the azo-method. Antisera obtained after immunization of rabbits with the TS_ill-_illl-(3-azophenyl)-flavazole-edestin conjugate contained TS_ill-specific antibodies, as shown by agglutination of S. illinois bacteria as test antigen (titers up to 1:2500). The specificity of these antibodies was tested in detail by cross-agglutination with various bacterial strains. These antibodies are predominantly directed against the non-reducing end group Glc Gal (Man) (O-factor 34), and only to a slight extent against the internal groupings' Gal Man (O-factor 15) and Man (Rha) (O-factor 3). The serum antibodies did not show cross-reactions with O-factor 12₂, which differs from O-factor 34 in the configuration of the Gal Man-linkage (12₂ :α-glycosidic, 34:β-glycosidic). Thus, by immunization of rabbits with a TS_ill-_illl-(3-azophenyl)-flavazole edestin conjugate, a largely factor-specific (anti-34) antiserum was obtained.     

The synthesis of dicarboxylie acids containing oxadiazole rings and polyamides derived from them

Novel dicarboxylic acids containing one or two 1,3,4-oxadiazole rings in a molecule were synthesized by the reaction between orthoesters and acid hydrazides These dicarboxylic acids have the following structures: and where R represents a phenylene or an alkylene group and n = 1-4. The polyamides from p-xylylenediamine with these dicarboxylic acids were also prepared. The polymers are generally insoluble in m-cresol but soluble in conc. sulfuric acid. The melting points were estimated at above 350°C. Copolyamides of high molecular weights with aliphatic polyamides were obtained.     

Zur berechnung der viskositätszahl aus einpunktmessungen

The theoretical basis of a process for determining [η] from a single value of the viscosity is discussed. The following equation for calculating [η] is derived:      

Production of organometallic polymers by the interfacial technique. XXI. A study of some associated reaction variables in the synthesis of poly[imino-1.4-phenyleneimino(dibutylstannylene)]

Polymers of the below form are synthesized via the interfacial polycondensation route. A study has been made of the influence of the nature of the solvents employed and base and reactant concentration. New interfacial solvent systems are presented.     

Perfluoropolyether structures as surface modifying agents of UV-curable systems

New functionalised macromers containing perfluoropolyether (PFPE) structures and methacrylic end groups were synthesised and used as modifying additives for acrylic UV-curable systems. Their chemical structure is Rh-Rf-Rh, where and with p ≈ q. Notwithstanding their very low concentration, below 0.5 wt.-%, the fluorinated macromers cause a dramatic change of the surface properties of the films, without changing their curing conditions and their bulk properties. X-ray photoelectron spectroscopy (XPS) measurements showed that the macromers are able to concentrate selectively at the surfaces of the films, depending on their chemical structure and on the kind of substrate employed.     

Studies on the polymerization of bifunctional monomers. X. Further studies on the cationic polymerization of o-divinylbenzene

Cationic cyclopolymerization of o-divinylbenzene was further investigated. The relationship between the cyclization constant (r_c) and the amount of pendant double bonds present in polymer was derived statistically, without resort to the kinetic steady state approximation. When the catalyst and the solvent were varied, the influence of the solvent polarity on r_c was small. However, different FRIEDEL-CRAFTS catalysts gave widely varied r_c values in the following order: This variation was correlated with the structure of the propagation ion-pair.     

Die substanzpolymerisation von acrylnitril

The bulk polymerization of acrylonitrile for conversions Q 15% was studied by means of an improved dilatometric technique and a new method of evaluation. Starting from the results of the kinetic analysis a novel and simple mechanism for the polymerization is deduced, that is in excellent agreement with the experimental data, as could be shown by integrating the rate-law. Said mechanism can be expressed by the following scheme: and denotes, that beside a polymerization in homogeneous solution, polymer growth alsoproceeds in heterogeneous state, where bimolecular terminations can be neglected. It could be shown further, that induction periods showing up at the beginning of the re-action are not caused by impurities in the monomer, as they were reproducible and dependent of the initial initiator concentration. The following rate constants were calculated resp. estimated for 60°C:      

Production of organometallic polymers by the interfacial technique. XXII. Synthesis of poly[alkylene(arylene)oxystannanes] using a new modified system

Poly[alkylene(arylene)oxystannanes] of the form below have been synthesized from dichlorostannanes and diols using a modified nonaqueous interfacial system consisting of acetonitrile and hydrocarbons. The products are preferentially capped with alcohol end-groups.     

Synthesis of some new poly(phosphonylhydrazides)

Polymers have been prepared from the condensation of phenylphosphonic diisocyanate with hydrazides using the interfacial technique. The polymers are believed to contain the following repeating structure: The reactivity of nitrogen compounds with phenylphosphonic diisocyanate is of the order amines > hydrazines ≈ hydrazides > ureas.     

Modelle und modellreaktionen für die halogenierung von cis- und trans-1.4-polybutadien. Ein beitrag zur stereochemie der „kopf-kopf-polyvinylhalogenide”︁

The all-cis and all-trans isomers of have been synthesized in order to investigate reaction models for cis- and trans-1.4-polybutadienes. The halogenation by means of pyridinium perbromide and pyridinium perchloride leads to these being model compounds for head-to-head poly(vinyl halides). Structural units with erythro configuration result from trans olefins, such with threo configuration from cis olefins. The characteristic C? X frequencies for trans and gauche positions of vicinal halogen atoms derived from infrared and RAMAN spectra are being determined: trans position ν_{C? Br} 550 to 560 cm^?1 (IR), 595–620 cm^?1 (Ra), ν_{C? Cl} 650–660 cm^?1 (IR), 670–690 cm^?1 (Ra), gauche position ν_{C? Br} 520–535 cm^?1 (IR, Ra), ν_{C? Cl} 550–560 cm^?1 and 590–610 cm^?1 (IR, Ra). On the basis of these values a local conformational analysis of the halogenated cis- and trans-1.4-polybutadienes has been made.     

Infrared spectroscopic study of the structural change of polymethacrylonitrile following heat-treatment and subsequent treatment with water

The infrared spectrum of polymethacrylonitrile (PMAN) exhibits noticeable change on heat-treatment up to 240°C, the color of the sample changed from yellowish at 120°C, through yellow and red, to deep red at 210°C or above. A new structure was proposed as a plausible structure for the chromophore of the heat-treated PMAN film, on the basis of comprehensive consideration of details of the spectral change in reference to the corresponding spectral change of polyacrylonitrile (PAN) and the spectra of compounds having similar structures. Subsequent treatment of the deep-red PMAN with hot water further drastically changed the infrared spectrum, and in turn the color changed from deep red to yellowish. The spectrum of the hydrolyzed product was in complete agreement with that of the copolymer of methacrylonitrile and methacrylic acid. Thus the structure was found to be from infrared spectral comparison.     

A New Technique for the Experimental Measurement of Monomer Partition Coefficients

Summary: A new method for the measurement of monomer partitioning for emulsion polymerisation is presented. The method is based on measuring the partition coefficients for films cast from different latexes. Its validity was demonstrated for methyl methacrylate (MMA) and butyl acrylate (BA), as well as for mixtures of these two species, by comparing the data to model predictions using literature data. The model predictions and experimental results agreed quite well for MMA, but less so for BA due to its extremely low water solubility.

     

The synthesis of α-tert-butyl-ω-[p-vinylphenyl]-terminated poly(2-methylpropene) macromonomers

In this communication a novel synthetic route to α-tert-butyl-ω-[p-vinylphenyl]xy1terminated poly(2-methylpropene) (PIB) macromonomers ( P3 (VB); P5 ) is described: and Attempts to synthesize such macromonomers in both one- and two-step syntheses are described. The one-step method using 4-chloromethylstyrene/AlR3 as initiating system for the polymerization of 2-methylpropene did not yield linear macromonomers but rather highly branched products. The alternative two-step synthesis using 1-(2-bromoethyl)-4-chloromethylbenzene (BCB) or BCB/AgSbF, as initiator also failed to yield the desired products. Successful syntheticroutes, optimised on the basis of model experiments with low molar mass compounds, are also described for preparing the above macromonomers. Both of these routes involve isopropenylterminated PIB, which is easily assessible by Inifer technique followed by dehydrohalogenation. Friedel-Crafts alkylation of phenol by the terminal olefin group of PIB, followed by subsequentesterification of the phenolic end-groups with 4-vinylbenzoyl chloride, affords the macromonomer P3(VB). Conversion of the terminal olefin group of PIB into a primary alcohol using 9-bora[3,3, I]-bicyclononane/H202, followed by esterification, yields the macromonomer P5 .     

Production of organometallic polymers by the interfacial technique. XI. Synthesis of poly(organotin esters) and a study of some associated reaction variables

Polyesters of the form below are prepared by the interfacial method. Isolation procedures are presented and discussed. Polymer yield is constant as stirring rate, stirring time and nature of the organic solvent are varied. Molecular weight is constant as stirring rate and organic solvent nature are varied. Molecular weight increases as reaction time increases. No correlation is found between polymer molecular weight and polymer softening range.     

Synthesis and Thermal Characterization of Perfluorocyclobutyl (PFCB) Polymers Containing Crown Ether Vertebrae

Summary: The synthesis and polymerization of novel 18‐crown‐6 and 24‐crown‐8 bis aryl trifluorovinyl ethers is described. Thermally induced polymerization yields linear crown ether fluoropolymers with hexafluorocyclobutyl linkages. The polymers exhibit T_g's above 120 °C and show good thermal stability with no appreciable weight loss below 350 °C. Incorporation of crown ether macrocycles into the polymer is expected to increase cationic uptake of an otherwise electroneutral fluoropolymer.

     

Preparation and Properties of Cholesteric Network Polymers Based on Liquid Crystalline Epoxides

Summary: Polyether network polymers with cholesteric superstructure are formed by the photochemically induced cationic copolymerisation of a nematic diepoxide with chiral epoxides. If a cholesteric superstructure is formed or not, depends on the temperature at which the photopolymerisation is carried out. The storage modulus is higher above T_G in samples with cholesteric superstructure. Optical rotations and vibrational circular dichroism spectra (VCD) depend strongly on the surface state of the substrates. From the VCD spectra it is concluded that the copolymerisation leads to different superstructures depending on the rub directions of the substrates.

IR absorption spectrum and VCD spectrum of the cholesterol derivative 4 .     

Microwave‐Assisted Synthesis of Poly(L‐lactic acid) via Direct Melt Polycondensation Using Solid Super‐Acids

A microwave‐assisted method of synthesizing high‐molecular‐weight PLA using SSA as green catalyst was developed. Yellowish PLA with above 2.0 × 10⁴ g · mol^?1 was obtained when the reaction was run at 260 °C within 60 min under microwave irradiation with 0.4 wt.‐% SSA. This method used only 10% of the energy consumption necessary for conventional heating, and the catalyst could be used five times without losing catalytic activity. The improvement in and the decrease in the energy consumption under microwave irradiation suggested that selective heating and hot spots effects played a crucial role. The method was shown to be a time‐saving, green and a promising way to lower the cost and spread the application of PLA.

     

Oligomerization of styrene by trichloroacetyl chloride

The thermal oligomerization of styrene at 60°C with trichloroacetyl chloride (TAC) was investigated. The initial rate of oligomerization can be described by the equation The analysis of the oligomers showed that the main component of the oligomers was a styrene trimer of the structure      

High‐Temperature Propagation and Termination Kinetics of Styrene to High Conversion Investigated by Electron Paramagnetic Resonance Spectroscopy

Summary: The free radical bulk polymerization of styrene at 120 °C has been investigated over almost the entire conversion range using electron paramagnetic resonance spectroscopy, Fourier‐transform near‐infrared spectroscopy and gel permeation chromatography. The free radical concentration went through a sharp maximum that coincided with the peak in the rate of polymerization during the gel effect, and shifted to higher conversion with increasing initiator concentration. The termination rate coefficient (k_t), decoupled from the initiator efficiency (f) by use of the instantaneous degree of polymerization, remained close to constant up to as high as approximately 80% conversion, at which a dramatic decrease occurred. Both the propagation rate coefficient (k_p) and f fell orders of magnitude near 80% conversion in spite of the temperature being above the glass transition temperature of the system. The value of k_p increased with the initiator concentration at a given conversion in the highest (diffusion‐controlled) conversion range.

Termination rate coefficient (k_t) versus conversion for bulk free radical polymerization of St initiated by TBP at 120 °C. [TBP] = 0.15 (○), 0.10 (?) and 0.05 M ().