Octene optimized conditions

Chitosan (Fig. 27) was deposited on sihca by precipitation. The palladium complex was shown to promote the enantioselective hydrogenation of ketones [80] with the results being highly dependent on the structure of the substrate. In the case of aromatic ketones, both yield and enantioselectiv-ity depend on the N/Pd molar ratio. Low palladium contents favored enan-tioselectivity but reduced the yield. Very high conversions were obtained with aliphatic ketones, although with modest enantioselectivities. More recently, the immobilized chitosan-Co complex was described as a catalyst for the enantioselective hydration of 1-octene [81]. Under optimal conditions, namely Co content 0.5 mmolg and 1-octene/Co molar ratio of 50, a 98% yield and 98% ee were obtained and the catalyst was reused five times without loss of activity or enantioselectivity. 

It is noteworthy that, in contrast to mammalian systems, the majority of bacterial strains exhibited sufficient activity even when the cells were grown under non-optimized conditions. Since enzyme induction is still a largely empirical task, cells were grown on standard media in the absence of inducers. Furthermore, all attempts to induce epoxide hydrolase activity in Pseudomonas aeruginosa NCIMB 9571 and Pseudomonas oleovorans ATCC 29347 by growing the cells on an alkane (decane) or alkene (1-octene) as the sole carbon source failed [27]. 

Recently, Lautens, Aspiotis and Colucci extended the [4+3] cycloaddition methodology to include the diastereoselective intermolecular cycloaddition between an oxyallyl cation and a chiral furan [45]. The best results were obtained employing furan 26 bearing a free hydroxyl group in the 2-position, reacting with excess 1,3-dibromopentanone in the presence of diethyl zinc. Under the optimized conditions, up to 80% yield of the crystalline oxabicyclo[3.2.1]octene 27 was obtained with a diastereoselectivity of a 19 1. The other product was the minor diastereomer 28, Eq. 17. 

Despite the limited solubility of 1-octene in the ionic catalyst phase, a remarkable activity of the platinum catalyst was achieved [turnover frequency (TOP) = 126 h ]. However, the system has to be carefully optimized to avoid significant formation of hydrogenated by-product. Detailed studies to identify the best reaction conditions revealed that, in the chlorostannate ionic liquid [BMIM]Cl/SnCl2 [X(SnCl2) = 0.55],... 

Optimal reaction conditions for the Se02/TBHP mediated hydroxylation of compounds containing allylic C-H bonds such as (Z)-2-octene (10) have been reported11,13. 

This study, performed on the hydroformylation of oct-l-ene, has shown that below 140°C nonanals are the predominant products with linearities of approximately 97% (99% in one run at I00°C), whereas above 180°C nonanol was obtained almost exclusively with high octene conversions (>98% at 200°C) but poor linearities (65%). At high temperatures a 10-fold excess of bipy increases the nonanol linearity (to 76%). This parameter is not very sensitive to the CO or partial pressures as the total pressure is above about 95 bar. The author (40) seems to prefer coordination of the alkenc to a ruthenium center or hydride transfer to form an alkyl ruthenium cluster as the two possible rate-determining steps. Thus, by optimization of the experimental conditions it is possible to reach high linearities (n/iso>100) for the hydroformylation of terminal alkenes by the [Ru3(CO),2]/bidentate nitrogen- or phosphorus-containing ligand/phos-... 

Under optimized reaction conditions (1.5 MPa, 100 °C), it appears that the chemoselectivity and n/i ratio in the hydroformylation of 1-octene are very dependent on the nature of the IL. The best results were obtained using pure [BMIM][PFg]. 

Copolymers of ethylene with a-olefins also known as LLDPE are an important topic due to their enhanced mechanical properties, structural simplicity, and industrial importance. Copolymers of ethylene with 1 -butene, 1-hexene, and 1-octene, have been obtained by copolymerization via Ziegler-Natta and metallocene chemistry.While many studies deal with modification of the catalyst and optimization of the reaction s conditions, thermal behavior of LLDPE is more important for understanding the morphology of these materials.Inspired by the success obtained modeling EP copolymers via ADMET polymerization, extension of this investigation led us to the synthesis of PE with only ethyl branches precisely placed along the main backbone, or precisely sequenced... 

Stabilizing the catalyst against acids was needed for the Rh/BINAS-catalyzed aqueous hydroformylation of internal olefins (see Table 5.1) [8]. Reaction rates were low (averaged TOF = 62h for 2-pentene), but very high regioselectivities of 99% toward the terminal aldehydes were obtained for the hydroformylation of 2-pentene and 2-octene, respectively, under optimized reaction conditions. Controlling pH was found to be essential to increase both the selectivity and the aldehyde yield. Best results were obtained in solutions buffered at pH 8-9, or with additional triethanolamine or TMEDA employed to trap formic acid suggested to be formed in a side reaction. 

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