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The effect of the molecular structure of feedstock on the cracking reaction of C10 hydrocarbons to ethylene and propylene over H-ZSM-5 zeolite was investigated. To better compare the effect of decane on the production of light olefins, the thermal cracking and catalytic cracking performance of decane were first investigated. As a comparison, the thermal cracking and catalytic cracking of decane were studied by cracking over quartz sand and H-ZSM-5. Compared with the thermal cracking reaction over quartz sand, the catalytic cracking reaction of decane over H-ZSM-5 has a significantly higher conversion and light olefins selectivity, especially when the reaction temperature was lower than 600 °C. On this basis, the catalytic cracking reactions of decane and decene over H-ZSM-5 were further compared. It was found that decene with a double bond structure had high reactivity over H-ZSM-5 and was almost completely converted, and the product was mainly olefin. Compared with decane as feedstock, it has a lower methane yield and higher selectivity of light olefins. Therefore, decene was more suitable for the production of light olefins than decane. To this end, we designed a new light olefin production process. Through olefin cracking, the yield of light olefins in the product can be effectively improved, and the proportion of different light olefins such as ethylene, propylene and butene can be flexibly adjusted.

Homo- and copolymers of propylene and 1-decene were synthesized by controlled chain-walking (co)polymerization using phenyl substituted &alpha, diimine nickel complexes activated with modified methylaluminoxane (MMAO). This catalytic system was found to polymerize propylene in a living fashion to furnish high molecular weight ethylene-propylene (EP) copolymers. The copolymerizations proceeded to give high molecular weight P/1-decene copolymers with narrow molecular weight distribution (Mw/Mn &asymp, 1.2), which indicated a living nature of copolymerization at room temperature. The random copolymerization results indicated the possibility of precise branched structure control, depending on the polymerization temperature and time.

For the first time, randomly methylated β-cyclodextrin was applied as the mass transfer agent in a continuous process. Considering the example of the Rh-catalyzed hydroformylation of 1-decene, process development was shown, where cyclodextrin was used together with a catalyst system that was continuously recovered and recycled using an aqueous biphasic system. In initial experiments, water-soluble and commercially available Rh/TPPTS and Rh/sulfoxantphos catalyst systems were scaled up from 50 ml into 1000 ml high-pressure autoclave systems to demonstrate their scalability. Both these systems were compared, and they afforded excellent chemoselectivity (>99%) toward the desired linear aldehyde product. In particular, higher regioselectivity (up to 31) was achieved for the Rh/sulfoxantphos system. Investigations regarding the long-term stability of the mass transfer agent and both catalyst systems were carried out in a continuously operated miniplant process. It was shown that the process could be successfully operated under the steady state for over 200 h with chemoselectivity of >97% toward the desired aldehyde product. Simultaneously, extremely low Rh leaching (total: 0.59%) was observed over the entire period of 200 h.

1-Phenylphosphol-2-ene 1-oxide is effectively resolved by L-menthyl bromoacetate to afford both SP and RP enantiomers of 1-phenylphosphol-2-ene 1-oxide on a multigram scale. The resolved 1-phenylphosphol-2-ene oxide has been found to undergo face-selective and endo-selective cycloadditions with a series of acyclic and cyclic dienes to produce enantiopure P-stereogenic C-P heterocycles of hexahydrophosphindole and hexahydrobenzophosphindole as well as phospha[5 .2.1.02,6]decene and phospha[5.2.2.02,6]undecene structures. Conversions of these cycloadducts to the fully saturated heterocyclic systems as well as to their P (III), P = S, P = Se and P-BH3 derivatives have been demonstrated to occur with retention of configuration and preservation of configurational homogeneity at P. A perplexing case of stereomutation at P during reduction of a tricyclic &beta, hydroxy phosphine oxide by PhSiH3 at 80 &deg, C has been recorded.

The experimental and model-based investigation of the palladium-catalyzed methoxycarbonylation of 1-decene using methanol and carbon monoxide is presented. The reaction was studied in a thermomorphic solvent system using the industrially applied ligand DTBPMB in order to describe the kinetics of the main and the most relevant side reactions. Based on a reaction analysis, kinetic models including main influencing variables were derived and successfully parametrized. Thus, inhibition effects of the substrate 1-decene as well as carbon monoxide on the isomerization and methoxycarbonylation rate could be identified.

Thermoplastic elastomers (TPEs) are attractive materials because they combine the processing advantages and recycling potential of thermoplastics with the flexibility, low modulus, and soft touch of elastomers. In this article, the synthesis, characterization and mechanical properties of polyolefin TPEs are reported. A facile procedure is employed, through the chain-walking polymerization, to fabricate random copolymers of 1-octene with 1-decene and cyclopentene. The effect of the type and the feedstock comonomers concentration on the microstructure, the total branching and the branch-type distribution is studied. A comprehensive investigation on the mechanical behavior by uniaxial stretching until failure, step-cycle and creep tensile tests is carried out. All the copolymers behave as elastomers, with different mechanical properties strongly depending on the composition, structure and crystallinity.

The stereoselective Diels–Alder reaction between an optically active 1,4-dimethylcycloheptadiene and acrolein was effectively promoted by TBSOTf to produce a bicyclo[3.2.2]nonene derivative bearing two quaternary carbons. Seven additional transformations from the obtained bicycle delivered the C2-symmetric bicyclo[3.3.2]decene derivative, a key intermediate in our synthetic study of ryanodine.

We synthesized polyethylene (PE), poly(ethylene-co-1-decene), poly(ethylene-co-p-methylstyrene) and poly(ethylene-ter-1-decene-ter-p-methystyrene) using a rac-Et(Ind)2ZrCl2 metallocene catalyst and a methylaluminoxane cocatalyst system. The materials were characterized using nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. We compared and studied the kinetics, thermal properties and mechanical ones of these polymers. Tg was related to the amorphous phase of the polymers, whereas the tensile strength and storage modulus (E’) were related to the crystalline phase. We also found that PE has the highest crystallinity through differential scanning calorimetry and wide-angle X-ray scattering analysis. The polymerization rates of poly(ethylene-co-1-decene) and poly(ethylene-ter-1-decene-ter-p-methystyrene) were always higher than that of polyethylene.

Fluorocarbon coatings were deposited by plasma polymerization of 1H,1H,2H-perfluoro-1-decene (HDFD). Chemical and morphological characterization of coatings obtained from different process parameters was performed by means of Attenuated Total Reflectance Fourier Transform Infrared (FTIR/ATR) spectroscopy, Energy Dispersive X-Ray analysis (EDX) and Atomic Force Microscopy (AFM). Hydro- and oleo-repellency were evaluated by contact angle measurements with different liquids. Optical properties were investigated by acquiring the transmittance spectra in the region 300–900 nm. Finally, evaluation of the mechanical properties was performed by means AFM nanoindentation. By increasing the Yasuda factor (the energy consumed per mass of monomer), coatings with lower retention of fluorocarbon chains were obtained. The F/C ratio, measured by means of EDX analysis, decreased from 0.85 for coatings deposited at 10 W to 0.69 for coatings deposited at 100 W. As a consequence of the lower retention of fluorocarbon chains, coatings deposited at high Yasuda factors displayed lower hydro- and oleo-repellency. In addition, these coatings contains large amount of unsaturated groups ([Formula presented], [Formula presented], …), as assessed by ATR analysis. This led to a lower transparency, due to radiation absorption in the visible region. On the other hand, the mechanical properties (and hence the durability) of the coatings increased with the energy consumed per monomer molecule.

The synthetic potential of stereoselective, palladium-catalyzed hydro(het)arylation reactions of bi-, tri- and tetracyclic (hetero)alkenes in the presence of phospines and arsines as highly efficient ligands was studied. The mechanism of this reductive Heck reaction becomes more complex in the case of benzonorbornenes. Hydroarylation of diazabicyclo-[2.2.1]heptenes provides a stereoselective access to aryldiaminocyclopentanes. Electron-deficient arylpalladium complexes shift the reaction towards the product of a formal 1,2-hydrazidoarylation reaction of 1,3-cyclopentadiene by a stereoselective C-N cleavage. Due to steric reasons, rigid bicyclo[2.2.2]octenes react slower in hydroarylation reactions than the corresponding bicyclo[2.2.1]heptenes. The more flexible bicyclo[4.2.2]decene system already tends to undergo domino-Heck reactions, even under reductive conditions. When a tetracyclic cis-allylcyclopropane is carbopalladated in the presence of formates, the neighboring cyclopropane ring is attacked in the first reported example of a pi,sigma domino-Heck reaction.

International audience; Different low melting mixtures (LMMs) based on N,N'-dimethylurea (DMU) and various cyclodextrin (CD) derivatives were synthetized. The melting point was weakly affected by the size and the chemical modification of CD. By contrast, the chemical modification of CD led to a decrease in viscosity of the LMMs. These mixtures were evaluated as solvent in rhodium-catalyzed hydroformylation reaction of 1-decene. The LMM based on DMU/RAME-beta-CD (70/30) allowed reaching the highest catalytic activity (1980 h(-1)). The influence of several factors was studied and it was established that the conversion increased with the 1-decene solubility and decreased with the LMM viscosity

New insights into the mechanism of thermal reactions of alkenes with hydrogen terminated silicon are presented. Scanning tunneling microscopy (STM) imaging at the early stages of the reaction of 1-decene with H/Si(111) at 150 degrees C confirm this reaction occurs via a propagating radical chain mechanism. In addition, evidence is presented for an initiation mechanism involving degradation of hydrocarbon molecules catalyzed by the silanol surface of Schlenk tubes commonly used in carrying out these reactions. Hydrogen-terminated silicon surfaces are found to be unstable in the "inert" solvent dodecane when heated at 150 degrees C in a Pyrex Schlenk tube. By contrast, the surfaces were significantly more stable at the same temperature when reactions were carried out in Teflon (polytetrafluoroethylene or PTFE). The thermal reaction of decene with H/Si(111) was found to proceed more rapidly in Pyrex than in PTFE, consistent with an impurity-based initiation mechanism.

The ability of PTA (PTA = 1,3,5-triaza-7-phosphaadamantane) and its N -benzylated derivative ( N -Bz-PTA)Cl to interact with the randomly methylated β-cyclodextrin (RAME-β-CD) has been studied by UV–vis and NMR spectroscopies. Both ligands could be considered as non-interacting phosphines with respect to RAME-β-CD. This has been turned to account in a rhodium-catalyzed hydroformylation reaction of 1-decene. A comparison with TPPTS (sodium salt of trisulfonated triphenylphosphine) highlights the beneficial effects of the PTA-based ligands on the chemoselectivity. Actually, chemoselectivities in aldehydes obtained with PTA and ( N -Bz-PTA)Cl were very high (>98%) whatever the temperature. Moreover, contrary to what was observed with TPPTS, no decrease in regioselectivity was noticed as the linear to branched aldehydes ratio remains constant.

Previous field ionization kinetic experiments have supported strongly that the double hydrogen migration prior to the elimination of C5H8 from the molecular ions of the endo isomers of 8,9-disubstituted tricyclo[5.2.1.02,6]decenes, which is not observed for the exo isomers, proceeds in a concerted, i.e., dyotropic way. This paper describes the results of ab initio calculations at the ROHF/4-31G and DFT level of theory, performed on the double hydrogen migration for the ionized endo isomer of unsubstituted tricyclo[5.2.1.02,6]decene. An intrinsic reaction coordinate calculation at the DFT level has shown indeed a direct connection between the structures of the molecular ions of the endo isomer before and after the double hydrogen migration, thus corroborating the earlier suggested concerted, i.e., dyotropic pathway of this double hydrogen rearrangement.