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Covering: 2000 to 2020. trans-Bicyclo[4.4.0]decane/decene (such as trans-decalin and trans-octalin)-containing natural products display a wide range of structural diversity and frequently exhibit potent and selective antibacterial activities. With one of the major factors in combatting antibiotic resistance being the discovery of novel scaffolds, the efficient construction of these natural products is an attractive pursuit in the development of novel antibiotics. This highlight aims to provide a critical analysis on how the presence of dense architectural and stereochemical complexity necessitated special strategies in the synthetic pursuits of these natural trans-bicyclo[4.4.0]decane/decene antibiotics.

Tungstate catalysts are well established for olefin epoxidation reactions, while their catalytic activity for CO2 insertion in epoxides is a more recent discovery. This dual reactivity of tungstate prompted the present development of a catalytic tandem process for the direct conversion of olefins into the corresponding cyclic organic carbonates (COCs). Each of the two steps was studied in the presence of the ammonium tungstate ionic liquid catalyst – [N8,8,8,1]2[WO4] – obtained via a benign procedure starting from ammonium methylcarbonate ionic liquids. The catalytic epoxidation first step was optimised on 1-decene as model substrate, using H2O2 as benign oxidant, [N8,8,8,1]2[WO4] as catalyst and phosphoric acid as promoter affording quantitative conversion with 92% selectivity towards decene oxide. Unfortunately, the addition of CO2 from the start (auto-tandem catalysis) gave low yields of decene carbonate (

Progress toward a convergent approach for the enantioselective synthesis of the Veratrum alkaloid jervine is presented. The two requisite fragments were stereoselectively and efficiently fashioned from economical and readily available reagents. Key reactions include (a) a highly diastereoselective Ireland—Claisen rearrangement to establish the necessary cis-relationship between the amine and methyl group on the tetrahydrofUran E-ring; (b) a diastereoselective selenoetherification reaction that enabled the assembly of the D/E oxaspiro [4.5] decene in the needed configuration; and (c) an enzymatic desymmetrization of an abundant achiral diol en route to a key four-carbon building block as a practical alternative to a protected Roche ester reduction.

Cyclic carbonate compounds are valuable for a range of applications and can be synthesized by a one-pot reaction involving epoxidation of olefin followed by reaction of the epoxide with CO2. This study used supported ruthenium catalysts for the epoxidation step (first step), where a combination of tetrapropylammonium bromide and zinc bromide was used for the cycloaddition of carbon dioxide. The supported ruthenium catalyst, prepared by a sol-immobilization method, allowed the effective epoxidation of 1-decene in air (using oxygen as the main oxidant) at 90 ºC in the presence of a catalytic quantity of radical initiator. This approach was applied to the one-pot multi-step oxidative carboxylation of 1-decene in the presence of 1 % Ru/support-Pr4NBr/ZnBr2 catalyst

The authors acknowledge the KAUST ACL Core Lab. This work was supported by funds from King Abdullah University of Science and Technology

An original approach to α-olefin oligomerization as well as novel thermally stable zirconocene catalysts for use in such reactions has been elaborated. The method reported allows the achievement of fractions of lightweight α-olefin oligomers up to 90% yields without considerable formation of byproducts like internal alkenes, alkanes, and higher oligomers. Trimers, tetramers, and pentamers of 1-hexene, 1-octene, and 1-decene were isolated as individual compounds and were hydrogenated. Viscosity characteristics of the isolated saturated and unsaturated hydrocarbons have been studied at various temperatures. The isolated saturated oligomers of 1-octene and 1-decene outperform the traditional electrophilic oligomerization products in terms of viscosity indexes, pour points, and low-temperature viscosity.

The construction of tricyclo[5.2.1.01,6]decene skeleton was achieved by cyclobutane ring formation via improved radical reaction using SmI2-H2O-HFIP and SmI2-LiCl conditions in good yields. Those additives were studied to increase the reactivity of SmI2. Two interesting reactions via neighboring group participations are described for introducing the C4 oxygen functionality by the assistance of C6 substituent in a regioselective manner.

Herein we report about an efficient isomerization/hydroformylation tandem reaction to convert a technical mixture of decene isomers selectively into the linear undecanal in a thermomorphic solvent system. By applying a rhodium/BIPHEPHOS catalyst a high turnover frequency of 375 h−1 and high regioselectivity of 92% for the linear product are achieved. Yields up to 70% of the linear aldehyde are obtained. The catalyst can be successfully separated from the product using a thermomorphic solvent system consisting of dimethyl formamide (catalyst phase) and dodecane (product phase). The leaching of the rhodium (0.6% of the initial amount) and phosphorus (1.2% of the initial amount) is very low. The catalyst was successfully recycled five times.

The article was dedicated to the copolymerization reaction of decylmethacrylate with decene-1. The copolymerizaion was realized with the participation of the inisiator the radical mechanism—izooil acid dinitrilyne. The learning of the polymerizaion reaction of decylmethacrylate with decene-1 shows that, it is possible to analyse the polymer connections having any molecular mass and content with the way of changing the monomers correlation and reaction temperature, that, it is possible to manage it knowing the regularities of the process. The effect of decylmethacrylate decene-1 copolymers to the viscosity-temperature properties has been learnt. As the result it has been showed that, using the joint polymers of decylmethacrylate—decene-1 in the content of the limpid oils as the thickener additive, it is possible to get the base oils with good viscosity-temperature properties.

Emeriones A–C (1–3), three highly methylated polyketides with bicyclo[4.2.0]octene and 3,6-dioxabicyclo[3.1.0]hexane functionalities, were isolated from Emericella nidulans. An additional peroxide bridge in compound 3 led to the construction of an unexpected 7,8-dioxatricyclo[4.2.2.02,5]decene scaffold. The structures of 1–3 were elucidated by comprehensive spectroscopic techniques, and their absolute configurations were confirmed by single-crystal X-ray crystallographic analyses and ECD calculations. Compound 1 shows weak inhibitory effects on NO production in LPS-induced RAW264.7 cells.

The mechanism of selective co-oligomerization of ethylene and 1-hexene by the catalyst [CrCl3(PNPOMe)] (a, PNPOMe = N,N-bis(bis(o-methoxyphenyl)phosphine)methylamine) has been explored in detail using the density functional theory (DFT) method. The full catalytic cycles for the formation of 1-hexene and 1-decenes were calculated on the basis of the metallacyclic mechanism, and the distribution of all decene isomers was explained by locating Gibbs free energy surfaces of various pathways, which is in good agreement with the experimental results. A spin surface crossing through a minimum energy crossing point (MECP) from a sextet to a quartet surface takes place before the formation of metallacyclopentane, which opens up a much lower energy pathway and thus facilitates the following co-oligomerization reactions. It is worth noting that β-hydrogen agostic-assisted hydrogen transfer is of crucial importance for the decomposition of the metallacycle intermediates to give 1-hexene or decenes. Moreover, an analy...

A series of distillable alkyl carbamate ionic liquids (ALKCARB ILs) have been prepared from CO 2 and an amine, and then treated with silver (I) oxide to give the task specific ionic liquids. The synthesized ionic liquids have been used for the separation of 1-decene selectively from the mixture of n-decane/1-decene at room temperature. Presence of CO 2 to form carbamate with alkyl amine in the synthesis of ionic liquids remarkably enhanced the separation of olefin from mixture; however in its absence silver containing amine solvent provided very poor separation under identical conditions.

An improved synthesis of rings DEF of solanoeclepin A has been achieved from ent-Hajos Parrish ketone. A key tricyclo[5.3.2.01,6]decene intermediate having an additional vinyl group as a precursor of a hydroxyl functionality was synthesized, in which the key steps included (i) a [2,3]-Wittig rearrangement to provide trans-hydroindene with C11(R)-configuration, (ii) the introduction of a vinyl group as a masked OH at C6, (iii) an oxymercurative aldol to synthesize the tricyclo[5.3.2.01,6]decene moiety, (iv) an oxidative C–C bond cleavage to yield an aldehyde and an unsaturated methyl ketone, and (v) a radical cyclization for the cyclobutane ring formation to provide the tricyclo[5.2.1.01,6]decene compound.

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 highly strained tricyclo[5.2.1.0(1,6)]decene skeleton of solanoeclepin A was synthesized through two key C-C bond forming processes; thus, a Hg(TFA)2-mediated oxymercuration followed an intramolecular aldol reaction to B and a SmI2-mediated cyclization of C between an aldehyde and an unsaturated ester to form the cyclobutane D having a tricyclo[5.2.1.0(1,6)]dodecene.

Growth characteristics of urea inclusion compounds with 1-decene, n-decane and mixture of 1-decene and n-decane (relative mass ratio = 1:1) were studied by CCD high-speed Camera. The present studies show that the speed of UICs growth in tunnel direction is faster than in vertical direction and the length of UICs with 1-decene is shorter than UICs with n-decane, and the length of UICs with mixture is between them due to the influence of the vinyl in 1-decene. The value of R = I (CH2)/ I (CH3) and M = I (CH CH2)/ I (CH3) in FTIR spectrum of UICs increasing with growth time demonstrates that urea prefers to include n-decane than 1-decene. 13 C CP/MAS NMR studies of UICs indicate that the arrangement of 1-decene in UICs is CH3⋯CH3 and CH CH2⋯CH2 CH. The arrangement of 1-decene in UICs leads to short chain of UICs with 1-decene in tunnel direction. The 13 C CP/MAS NMR spectra of UICs with MIX reveal that there are three different types of arrangement: CH3⋯CH3, CH CH2⋯CH3 and CH CH2⋯CH2 CH. The methods of FTIR and DSC were used to test the stability of UICs with different guests. The result shows that UICs with n-decane are stable than UICs with 1-decene. And the stability of UICs with mixture is in the middle.

Polymerizations of 1-decene (DC), 1-dodecene (DD), and 1-tetradecene (TD) by Cp*TiMe2(O-2,6-iPr2C6H3) (1)&ndash, [Ph3C][B(C6F5)4] (borate) catalyst have been explored in the presence of Al cocatalyst. The polymerizations of DC and DD, in n-hexane containing a mixture of AliBu3 and Al(n-C8H17)3, proceeded with high catalytic activities in a quasi-living manner, affording high molecular weight polymers (activity 4120&ndash, 5860 kg-poly(DC)/mol-Ti&middot, h, Mn for poly(DC) = 7.04&ndash, 7.82 &times, 105, after 20 min at &minus, 30 &deg, C). The PDI (Mw/Mn) values in the resultant polymers decreased upon increasing the ratio of Al(n-C8H17)3/AliBu3 with decreasing the activities at &minus, C. The PDI values also became low when these polymerizations were conducted at low temperatures (&minus, 40 or &minus, 50 &deg, C), high molecular weight poly(DD) with low PDI (Mn = 5.26 &times, 105, Mw/Mn = 1.16) was obtained at &minus, C. The TD polymerization using 1&ndash, borate&ndash, AliBu3 catalyst (conducted in n-hexane at &minus, C) afforded ultrahigh molecular weight poly(TD) (Mn = 1.02 &times, 106, Mw/Mn = 1.38), and the PDI values also decreased with increasing the Al(n-C8H17)3/AliBu3 ratio.

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.

A pseudo four-component reaction of urea or thiourea, diverse aryl aldehydes, and 3-methyl-1-phenyl-2-pyrazolin-5-one in ionic liquids yields novel azaspiro[4.5]decene derivatives. However, the corresponding reaction in volatile organic solvents gives Knoevenagel adduct as a major product with little amount of the title compound. Interestingly, the expected pyrimidine derivative was not formed in any case. The advantageous features of this methodology are the environmentally benign character, operational simplicity, high yield processing, and easy handling without any catalyst. All the compounds were subjected to in vitro antimicrobial screening against a panel of pathogenic strains of bacteria and fungi. Some of the compounds were found to be equipotent or more potent than the commercial antibiotics.

An autothermal staged reactor was assembled containing a top stage of Rh-Ce/alpha-Al2O3 which generated heat and H-2 by reacting CH4 and air that passed through a downstream stage containing 0.5 wt% Pt/gamma-Al2O3 mixed with either HBEA, HZSM-5, or USY in a heat-integrated non-isothermal reactor. The H-2 produced subsequently reacts in a 20:1 ratio with a co-feed of hexane or decane or 2-decanone fed to the reactor between the stages. The large-sized pores of HBEA and USY allowed deoxygenation of 2-decanone to form decene isomers which can crack or cyclize to form up to a 36% yield of methylated and ethylated monoaromatics. The medium-sized pores of HZSM-5 restricted decene formation from 2-decanone by catalyzing cracking reactions to C2-6 compounds which can cyclize to form aromatics. By contrast, the reactor effluent from non-oxygenated reactants decane and hexane contained less than 5% aromatics. Thus, we extend the scope of staged autothermal reactor functionality to hydrocracking and hydroisomerization of higher saturated and oxygenated hydrocarbons. (C) 2012 Elsevier B.V. All rights reserved.

A new mechanism for the origin of multiple skeletal isomers observed in the cationic dimerization of 1-decene is proposed, and products that should form based on this mechanism are predicted. A protonated cyclopropyl intermediate appeared to form directly from combination of 2-decyl carbocation with 1-decene; formation of this intermediate did not appear to occur via ring closure of a branched secondary carbocation. The authors propose that rapid, repeated isomerizations of the protonated cyclopropyl intermediates lead to multiple skeletal isomers in decene dimers. The proposed mechanism can account for structures previously identified in mixtures of decene dimers and butene dimers. Copyright © 2012 John Wiley & Sons, Ltd.

The stereocontrolled synthesis of the highly strained, tricyclo[5.2.1.0(1,6)]decene skeleton (C) of solanoeclepin A has been achieved through two key transformations: a [2,3]-Wittig rearrangement of allylpropargyl ether (A) to propargyl alcohol (B) having a trans-fused perhydroindane framework and the formation of the cyclobutane via a cobalt-mediated Hosomi-Sakurai type cyclization of an acetylene dicobalthexacarbonyl complex.

When mixed with a water-soluble phos- phane capable of self-assembling into micelles, native or modified b-cyclodextrins (b-CDs) show very contrasting behavior depending on their neutral or ionic nature. In the post-micellar region, neutral b-CDs led to a micelle destructuring. Conversely, mi- celles remained stable over a well-defined range of ionic b-CD concentrations. In that case, the micelle destruction was only observed when using a large excess of ionic b-CDs. The catalytic performances of these micellar systems have been evaluated in a rho- dium-catalyzed hydroformylation reaction of 1- decene. We showed that, using ionic b-CDs, the cata- lytic activity could be improved without a detrimental impact upon the regioselectivity. A linear/branched aldehyde ratio as high as 8.6 could be achieved. The best results were obtained with stoichiometric quan- tities of ionic randomly methylated b-CDs with re- spect to the phosphane with a beneficial effect on the decantation at the end of the reaction.

Mixing of [(PBP)PtCl] complex with 1-decene and H2O afforded isomerized alkenes. Deuterium-labeling experiment indicated the catalytically active hydride species for alkene isomerization formed fro...

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.

Poly-alpha-olefin (PAO) was researched over acidic ionic liquid catalyzed the oligomerization of 1-decene. Ionic liquid used was 1-butyl-3-methyl imidazolium as a cation and aluminum chloride as an anion, which could effectively catalyze oligomerization and had a higher selectivity. The optimum process conditions for the synthesis of PAO were that the reaction temperature was 160°C, the reaction time was 3 h, the mole ratio between AlCl3 and [Bmim]Cl was 2.5:1, and the count of catalyst was 3 wt%. The components of product were analyzed with gas chromatograph, and the test results showed that the conversion of 1-decene was 74%. The product was the mixture of dimer, trimer, tetramer, and pentamer.

The kinetic characteristics of the autooxidation and initiated oxidation of decene oligomers PAO-2, PAO-4, PAO-6, and PAO-10+ at 120°C were studied. The mechanism of the oxidation of PAO-2 fraction is examined in detail using a mathematical model. The key reactions in the mechanism of PAO-2 oxidation at 120, 130, and 140°C are identified and the kinetic parameters determined. It is shown that the high oxidizability of an oligomer is determined not only by the presence of double bonds and hydroperoxides in samples, but also by high rates of chain initiation and decomposition of hydroperoxides with formation of free radicals. A comparative study of the mechanism of oxidation of a PAO-2 sample prepared using an alternative technology was carried out. It is shown that both the qualitative and quantitative parameters of the oxidation stability of the produced oligomer depend on the production technology. With the aim of enhancing oxidation stability of the initial nonhydrogenated products of oligomerization, the process of oxidation of PAO-2 sample was studied in the presence of antioxidants based on sterically hindered phenols and aromatic amines. It is demonstrated that such inhibitors can be used for anti-oxidation protection of the primary oligomerization products during their storage.

The catalytic asymmetric intramolecular cyclopropanation (CAIMCP)of α-diazo-β-keto sulfones developed in our laboratoryand applications to the total synthesis of natural products are described.CAIMCP features (a) a wide applicability, not only to the preparationof bicyclo[n.1.0]alkanes and tricyclo[4.n.0.0]alkenes, butalso to the enantioselective total synthesis of natural products, (b)the formation of highly crystalline products, which facilitate the productionof enantiomerically pure synthetic intermediates, and (c) the generationof products with a variety of functionalities, such as cyclopropane,ketone, and sulfone, beneficial to the total synthesis of naturalproducts. 1 Introduction 2 Preparation of Substrates 3 Synthesis of Carbocyclic Ring Systems by CAIMCP 3.1 Synthesis of the Bicyclo[3.1.0]hexaneSystem by CAIMCP of α-Diazo-β-Keto Sulfones 3.2 Synthesis of the Bicyclo[3.1.0]hexaneSystem with an Aryl Substituent by CAIMCP of α-Diazo-β-KetoSulfones 3.3 Synthesis of the Bicyclo[3.1.0]hexaneSystem by CAIMCP of α-Diazo-β-Keto Esters 3.4 Synthesis of the Bicyclo[4.1.0]hexaneSystem by CAIMCP of α-Diazo-β-Keto Sulfones 3.5 Synthesis of Tricyclo[4.3.0.0]nonene andTricyclo-[4.4.0.0]decene Systems by CAIMCP of α-Diazo-β-Keto Sulfones 3.6 Synthesis of the Tricyclo[4.4.0.0]deceneSystem by CAIMCP of α-Diazo-β-Keto Esters 4 Applications of CAIMCP to Natural Product Synthesis 4.1 Enantioselective Total Synthesis of (-)-Malyngolide 4.2 Enantioselective Total Synthesis of (-)-MethylJasmonate 4.3 Enantioselective Total Synthesis of (+)-Digitoxigenin 4.4 Enantioselective Total Synthesis of (+)-AllocyathinB 2 4.5 Enantioselective Total Synthesis of (-)-ErinacineB and (-)-Erinacine E 5 Conclusion

The performance of an 8 wt% WO3/SiO2 catalyst has been investigated for the metathesis of 1-hexene in a gas-phase fixed-bed reactor. The operating conditions (reaction temperature, feed composition and space time) were optimized for the yield of decene, the primary metathesis product, using a full factorial experimental design and a probabilistic two-factor search. A combined sequence of oxidative and reductive catalyst pre-treatments, followed by a nitrogen purge, led to the best yields of decene. It was found that at 380 °C, with 55 mol% 1-hexene in the feed and at 2874 g min mol−1, a decene yield of 12.8% can be obtained, with a 1-hexene conversion of 94%. Pre-treatment of the catalyst with only hydrogen and nitrogen resulted in a lower conversion of 1-hexene, selectivity and yield of primary products, possibly due to over-reduction of the active tungsten surface phase. Under the experimental conditions employed, the reaction was neither limited by extra- nor intraparticle mass transfer resistance effects.

A versatile two-step method has been developed that allows linking of biomolecules covalently to hydrogen-terminated group-IV semiconductors by means of epoxy-alkenes. First, the terminal C==C double bond of the alkene forms a covalent bond with the silicon, germanium, or diamond surface by UV-mediated hydrosilylation. The terminal oxirane moiety then reacts with the biomolecule. As a model system, we investigated the attachment of an esterase B to a Si(111) surface by means of the linker molecule 1,2-epoxy-9-decene. Samples were characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy. The immobilized enzyme retained its activity and exhibited good long-term stability.

Novel catalytic systems for the cationic oligomerization of 1-decene into synthetic poly(α-olefin) oils have been worked out; these systems include a highly disperse (0.1–40 μm) aluminum, an aluminum activator [I2, Mg, (C2H5)nAlCl3 − n, (CH3)3CCl and some other RX, HCl, benzene, and toluene], and a cocatalyst based on organic halide compounds RX (R is primary, secondary, or tertiary alkyl, allyl, or benzyl; X is Cl, Br, or I). We study the effect of various factors (characteristics of Al, nature of aluminum activator, RCl: Al molar ratio in the catalyst, concentration of Al, temperature, benzene additives, reaction duration) on the conversion of 1-decene into poly(α-olefins), the fractional composition of oligomerization products, the content of chlorine in poly(α-olefins), and the structure and physicochemical characteristics of fractions.

The kinetics of autoxidation and initiated oxidation of PAO-2, PAO-4, PAO-6, and PAO-10+ decene oligomer fractions at 140°C after a hydrogenation process was studied. Key reactions in the mechanism of oxidation were identified; the numerical values of the kinetic parameters were determined, and mathematical models, which quantitatively described the experimental data on the consumption of oxygen and the buildup of hydroperoxides during the course of the oxidation of the test samples, were obtained. The oxidation resistances of hydrogenated fractions were compared with each other. It was found that the kinetic parameters of the test samples were similar, and the oxidation of all of the hydrogenated oligomers occurred by approximately the same processes. Using the PAO-2 fraction at 120, 130, and 140°C as an example, the oxidizability of hydrogenated and unhydrogenated samples was compared. It was found that hydrogenation improved all of the kinetic characteristics and, consequently, increased the oxidation resistance of oligomers. However, the oligomers remained readily oxidizable substances, particularly, at elevated temperatures.

The enantioselective preparation of the tricyclo[4.4.0.05,7]dec-2-ene derivatives via the catalytic asymmetric intramolecular cyclopropanation (CAIMCP) reactions of α-diazo-β-keto esters with excellent ee (95–98% ee) is described. The chiral building blocks reported herein would be versatile intermediates for enantioselective natural products synthesis.

This article extends the composition of linear low-density polyethylene (LLDPE) resins to that containing 1-decene comonomer units, and examines the effects of comonomer (type and concentration) to copolymerization and physical properties of LLDPE resins. CGC metallocene technology, under high temperature and high pressure (industrial reaction condition), was used to prepare three types of well-defined LLDPE copolymers containing 1-hexene, 1-octene, and 1-decene units. They show high molecular weight with narrow molecular weight and composition distributions, comparative catalyst activities, and similar comonomer effects. However, 1-decene seems to exhibit significantly higher comonomer incorporation than 1-hexene and 1-octene, which may be associated with its high boiling point, maintaining liquid phase during the polymerization. The resulting LLDPE copolymers show a clear structure–property relationship. Melting temperature and crystallinity of the copolymer are governed by mole % of comonomer. The increase of branch density linearly decreases the LLDPE melting point and exponential reduction of its crystallinity. On the other hand, the density of the copolymer decreases with the increase of comonomer weight %, which shows a sharp linear relationship in the low comonomer content. The tensile properties of 1-decene-based LLDPE are very comparative with those of the commercial LLDPE resins with similar compositions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 639–649, 2007

A synthetic strategy to control the density of Mn12 clusters anchored on silicon(100) was investigated. Diluted monolayers suitable for Mn12 anchoring were prepared by Si-grafting mixtures of the methyl 10-undecylenoate precursor ligand with 1-decene spectator spacers. Different ratios of these mixtures were tested. The grafted surfaces were hydrolyzed to reveal the carboxylic groups available for the subsequent exchange with the [Mn12O12(OAc)16(H2O)4]4 H2O2 AcOH cluster. Modified surfaces were analyzed by attenuated total reflection (ATR)-FTIR spectroscopy, X-ray photoemission spectroscopy (XPS), and AFM imaging. Results of XPS and ATR-FTIR spectroscopy show that the surface mole ratio between grafted ester and decene is higher than in the source solution. The surface density of the Mn12 cluster is, in turn, strictly proportional to the ester mole fraction. Well-resolved and isolated clusters were observed by AFM, using a diluted ester/decene 1:1 solution.

In this paper, we report the complete 13C NMR characterization of a set of ethylene–propylene–1-octadecene terpolymers obtained with the metallocenic system rac-ethylene bis-indenyl zirconium dichloride, using different comonomer ratios. A detailed study of 13C NMR chemical shifts, triad sequence distributions, monomer average sequence lengths and reactivity ratios for these terpolymers is presented. The incorporations of 1-octadecene were superior of those obtained using 1-hexene and 1-decene in the same conditions. Catalytic activities of terpolymers of ethylene–propylene and α-olefins (α-olefins:1-hexene, 1-decene and 1-octadecene) were compared showing that they increase with the amount of propylene in the feed.

Interaction between α-cyclodextrin or β-cyclodextrin and the alkyl sulfonated diphosphines DPPETS (tetrasulfonated 1,2-bis(diphenylphosphino)ethane), DPPPTS (tetrasulfonated 1,3-bis(diphenylphosphino)propane) and DPPBTS (tetrasulfonated 1,4-bis(diphenylphosphino)butane) was investigated by NMR and UV-Visible spectroscopy. Contrary to α-cyclodextrin, β-cyclodextrin forms inclusion complexes with each sulfonated diphosphine. Continuous variation plots and titration experiments obtained from 1H and 31P NMR data indicated the formation of 1∶1 inclusion complexes and allowed the calculation of the association constants for each complex. Information on the structures of these complexes were obtained by T-ROESY NMR experiments. The potential of these ligands associated with methylated α- or β-cyclodextrin during the reaction of hydroformylation of 1-decene was studied. In all cases, the presence of cyclodextrins increased the conversion and the chemoselectivity whereas the linear to branched ratio of the aldehyde product decreased. This decrease in regioselectivity was attributed to the formation of low-coordinated phosphine species. In fact, in order to reduce steric hindrance around the metal center, a mono-dissociation of the bidentate ligand seemed to occur when the inclusion complex between the cyclodextrin and 1-decene approached the metal center. In the case of methylated-β-cyclodextrin, the phenomenon is accentuated since one of the two diphenylphosphino groups of the bidentate could be trapped by this cyclodextrin leading to the formation of a second-sphere coordination adduct.

Oligomer of 1-decene was synthesized with Ziegler–Natta catalyst which consisted of TiCl4 and Et2AlCl, using MgCl2 as support. The effects of temperature, Al/Ti ratio, time, and concentration of the catalyst on polymerization behaviors were investigated. The results showed that the catalyst system was desirable for the oligomerization of 1-decene with good catalytic activity, 143.8 kg oligo/mol Ti h, under typical conditions. The oligomer obtained was characterized with GC–MASS, GC and 13C NMR methods. Those results indicated that the oligomer was of a mixture consisting of di-, tri-, tetra- and pentamer. The 13C NMR data also implied that chain propagation of the oligomer involved primarily head-to-tail 1,2-insertions, as well as head-to-head and tail-to-tail 2,1-insertions.

Quaternary ammonium salts obtained by quaternization of lambertian acid 16-dialkylaminomethyl derivatives effected by allyl halides or propargyl bromide undergo intramolecular [4+2]-cycloaddition resulting in diterpenoids of labdane type containing a heterocyclic fragment of 10-oxa-3-azatricyclo[5.2.1.01,5]decene or 10-oxa-3-azatricyclo[5.2.1.01,5]deca-6,8-diene.

General methodology for the preparation of allyltin derivatives is reported, with special attention paid to sugar allyltins. Typical procedures affording such organometallics involve the conversion of partially protected hexoses or pentoses (Sug–CH2OH) into homologated allylic alcohols (Sug–CH=CH–CH2OH), which are further transformed into the primary or secondary sugar allyltin derivatives of the general formula Sug–CH=CH–CH2SnR3, (E)/(Z) ratio ≈ 5:1, or Sug–CH*(SnR3)–CH=CH2 (single isomer with the (S)-configuration at the newly created chiral center*). Controlled Lewis acid-induced fragmentation of these hexose-derived organometallics provides highly oxygenated dienoaldehydes with the (E) geometry across the internal double bond: CH2=CH–CH=CH–[CH(OR)]3–CHO. The (Z)-dienoaldehydes are also available by thermal fragmentation of the secondary sugar allyltins. Both these synthons ((E) and (Z)) can be further converted into highly functionalized derivatives of bicyclo[4.3.0]nonene and bicyclo[4.4.0]decene. Stereochemical aspects of reactions between sugar allyltins and sugar aldehydes (in the presence of Lewis acids or under high pressure) are also discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Under a pressure tuned supercritical fluid mixture of pentane/hexane as the media and using Co/A12O3 as the catalyst, the Fischer–Tropsch synthesis (FTS) reaction was conducted in a fixed bed reactor. 14C-labeled decene, tetradecene, and nonadecene were chosen as probe compounds to study the chemical behavior of the added mid-carbon number olefin under FTS supercritical reaction conditions. In the case of the run with decene, 21.8% of the added decene was reduced to decane, 73.5% remained unchanged, and only 4.7% of the added decene was incorporated into higher carbon number compounds. For the tetradecene and nonadecene runs, the percentages of reduction of the added olefin are 23.4 and 2.5%, while the percentages of incorporation are 2.6 and 1.5%, respectively. The molar radioactivity of the incorporated compounds decreases with increasing molecular size, indicating the presence of some accumulated products under these reaction conditions. The α value calculated based on the relative radioactivity of the incorporated compounds is 0.62, which is smaller than the value obtained from normal FTS under the same reaction conditions. These results indicate that the added mid-carbon number olefin cannot significantly alter the product distribution in favoring the heavier products.

Binary cooligomers of C7 and C10 α-olefins with 2-propenylphenol were synthesized in the presence of a complex catalyst based on aluminum chloride, toluene, and ethyl chloride (1:3.0:0.6 mol). Tests of the cooligomers as antimicrobial additives to I-12A oil showed that, in concentrations of 0.25 and 0.5%, they inhibit fungal growth, being superior to 8-hydroxyquinoline (reference) in the efficiency of action.

Design of supports containing a hyperbranched backbone and active transition metal centers at the periphery is described. Such nanoarchitectures can be easily assembled from 3,5-dihydroxybenzyl alcohol and dimethylsilylamine using a divergent synthetic methodology. Following a controlled reaction pathway, construction of dendrimers of up to generation 5 is achieved, while a simple mix of reagents in one-pot or with sequential additions yields analogous hyperbranched polymers. Subsequent functionalization at the periphery with phosphine followed by Rh(I) centers yields the desired metallodendritic materials. The efficiency of the latter in catalytic hydrogenation of decene under varied conditions is surveyed.

Many studies have been reported on the 13C NMR characterization of ethylene–α-olefin copolymers, but only a few have been reported on terpolymers. The incorporation of an α-olefin into the polyethylene chain changes the structure and, consequently, the properties of the polymer obtained. Looking for new products, we obtained a series of ethylene–propylene–1-decene terpolymers with the metallocenic system rac-ethylene bisindenyl zirconium dichloride/methylaluminoxane. We performed a complete 13C NMR characterization of these terpolymers qualitatively and quantitatively. Here we present a detailed study of the 13C NMR chemical shifts, triad sequence distributions, monomer average sequence lengths, and reactivity ratios for these terpolymers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2531–2541, 2003

A novel water soluble phosphine, N , N -dipolyoxyethylene-substituted-2-(diphenylphosphino)phenylamine (PEO–DPPPA), was synthesized by a two-step ethoxylation of 2-(diphenylphosphino)phenylamine (2-Ph 2 P–C 6 H 4 NH 2 , DPPPA). In the first step, DPPPA was ethoxylated without catalyst to give an intermediate with an average polyethylene glycol (PEG) chain length ( L = m + n ) of 3. Thereafter, this intermediate was further ethoxylated by using KOH as a catalyst to obtain the products with needed values of L . The solubility of the products in water increases with increasing of L . When L is more than 35, the products are water-soluble and possess the property of inverse temperature-dependent solubility in water (cloud point, C p ) as nonionic surfactants. The PEO–DPPPA/Rh complex catalyst formed in situ by RhCl 3 ·3H 2 O and PEO–DPPPA ( L =45) has been applied to the aqueous–organic biphasic hydroformylation of 1-decene. The conversion of olefin and the yield of aldehyde are 99.5 and 99.0%, respectively, under the conditions of 120 °C, 5.0 MPa (CO/H 2 =1), P/Rh=4 (molar ratio), 1-decene/Rh=1000 (molar ratio) and 5 h. Recycling test shows that both the conversion of olefin and the yield of aldehyde are still higher than 94.0% even after the catalyst has been recycled 20 times. The high reactivity of PEO–DPPPA/Rh complex can be attributed to a process termed thermoregulated phase transfer catalysis.

Three new spirocyclic sesquiterpenes designated exiguamide ( 1 ), exicarbamate ( 2 ) and exigurin ( 3 ), together with (−)-10- epi -axisonitrile-3 ( 4 ), have been isolated from the marine sponge Geodia exigua . All four compounds possess the spiro[4.5]decene skeleton and their structures were determined on the basis of spectroscopic data. The structure of 1 was confirmed by X-ray crystallographic analysis and the absolute configuration was determined by applying the modified Mosher's method on its amine derivative. Exiguamide ( 1 ) inhibited cell fate specification during sea urchin embryogenesis at a minimum inhibitory concentration of 0.4 μM.

Friedel-Crafts alkylation and acylation reactions, using highly polluting homogeneous Lewis and Bronsted acids, are ubiquitous in a variety of organic process industries. In many cases very high conversions and selectivities can be achieved with aluminum chloride as catalyst and nitrobenzene as a solvent. However, environmental concerns associated with aluminum chloride-nitrobenzene or BF3-HF or mineral acids catalysts have encouraged development of solid acids, which not only intensify the rates of reactions but also offer better product selectivity. Amongst these catalysts, sulfated zirconia has gained a considerable importance due to its super-acidity under certain conditions. The alkylation of diphenyl oxide with 1-decene was studied over sulfated zirconia catalyst and it leads to industrially important products. The surface reaction between chemisorbed 1-decene diphenyl oxide from the liquid phase, in the absence of any mass transfer resistance, was found to be the rate determining step with Eley-Rideal type of mechanism.