Octenes epoxidation

Olefin epoxidation is an important industrial domain. The general approach of SOMC in this large area was to understand better the elementary steps of this reaction catalyzed by silica-supported titanium complexes, to identify precisely reaction intermediates and to explain catalyst deachvahon and titanium lixiviation that take place in the industrial Shell SMPO (styrene monomer propylene oxide) process [73]. (=SiO) Ti(OCap)4 (OCap=OR, OSiRs, OR R = hydrocarbyl) supported on MCM-41 have been evaluated as catalysts for 1-octene epoxidation by tert-butyl hydroperoxide (TBHP). Initial activity, selechvity and chemical evolution have been followed. In all cases the major product is 1,2-epoxyoctane, the diol corresponding to hydrolysis never being detected. 

Table3.7 Comparison ofinitial activities ofvarious MCM-41(soo) supported titanium complexes for 1 -octene epoxidation by TBHPat80°C (1-octene TBHP Ti = 3000 150 1).

Octene, 567 rro s-3-Octene, 577 c/s-4-Octene-l, 7-diyne, 913 tra s-4-Octene epoxide, 1192... 

Propylene epoxidation conditions catalyst weight 0.3 g hydroperoxide 5 mmol solvent 100 ml epoxidation time 1 h epoxidation temperature 100 °C propylene pressure 8 bar. 1-Octene epoxidation conditions catalyst weight 0.3 g hydroperoxide 5 mmol 1-octene 100 ml epoxidation time 1 h epoxidation temperature 110 °C. 

Packed-bed reactor operation was used to test the stability of the CVD-prepared Ti/Si02 catalysts. For simplification, the reaction used was the epoxidation of 1-ocfene with TBUP. It is much easier and simpler to carry out 1-octene epoxidation (than propylene epoxidation) in a packed-bed reactor because 1-octene (boiling point, b.p. = 122 °C) is a liquid under the reaction temperature (110 °C). No decay of 1,2-epoxyoctane yield was observed during 12 h of continuous operation with the packed-bed reactor, therefore, the CVD-prepared Ti/Si02 catalysts were stable under continuous operation conditions. 

Table 14.1 also presents the turnover frequencies (TOF) of the CVD-prepared Ti/Si02 catalysts. For 1-octene epoxidation with TBHP in a batch reactor at 110 °C... 

Suspension polycondensation of pyromellitic dianhydride and 3,5-diamino-1,2,4-triazole yielded triazole-containing polyimide beads that were used as a support for Mo02(acac)2 [60]. The resulting catalyst showed high activity and selectivity in the epoxidation of cyclohexene and cycloctene as well as in the epoxidation of noncyclic alkenes such as styrene, 1-octene, and 1-decene with TBHP. The catalyst could be recycled 10 times and activity decreased significantly in the case of 1-octene epoxidation whereas activity remained high in the epoxidation of cyclic alkenes. 

Turnover numbers (T.O.N.) after 24 h, epoxide yield (mmol) and product distribution (%) for the 1-octene epoxidation with Ti-MCM-41 using tertiary butylhydroperoxide as oxidant. 

Jones and Vogel investigated the snbstitnent effect of a 5,6-bis(methoxycarbonyl) group in bicyclo[2.2.2]octene (48i) [117]. The substituent effect of a single 5-exo substituent on the facial selectivities of bicyclo[2.2.2]octenes 48b-48h was also characterized by our group [118]. Epoxidation and dihydroxylation of the olefin moiety of 5-exo-substituted... 

Epoxidation of olefins (e.g. 1-octene) to optically active epoxides... 

The enzyme catalysed epoxidation of alpha-olefins like 1-octene with oxygen to the optically active epoxide provides an interesting example of a four-phase system (de Bont et al., 1983). The hold-up of the organic phase may be 2-4 % and the presence of biosurface active agents leads to the creation of a large liquid-liquid interfacial area the liquid droplet size becomes smaller than the gas-liquid diffusion film thickness. 

Following a published procedure [1], octene was treated with a solution of perox-yacetic acid in acetic acid for 8 h to form the epoxide, but the reaction mixture was then allowed to stand uncooled overnight. Next morning, when a 3pl sample was injected into a heated GLC injection port, the syringe shattered. This was attributed to formation of diacetyl peroxide during the overnight standing, and its subsequent explosion in the heated port [2],... 

The more hindered alkoxide Ti(OiPr)4 was used as the precursor complex with surface silanols of an amorphous silica support this reaction is reported to lead to the same environment of Ti as in TS-1, but only when the reaction is carried in cyclohexanol as the solvent. Epoxidation of octene, cyclohexenol, and norbornene with FI202 in phenylethanol leads to 95-98% epoxide selectivity.147... 

The detailed kinetic study of octene-1 epoxidation by. veodecylsulfonic peracid was performed [25,42]. The 1,2-octanediol monodecylsulfonate was identified as the main product of the reaction. The kinetic dependence of the reaction rate (v) on the reactants concentration obeys the equation... 

The results of the olefin oxidation catalyzed by 19, 57, and 59-62 are summarized in Tables VI-VIII. Table VI shows that linear terminal olefins are selectively oxidized to 2-ketones, whereas cyclic olefins (cyclohexene and norbomene) are selectively oxidized to epoxides. Cyclopentene shows exceptional behavior, it is oxidized exclusively to cyclopentanone without any production of epoxypentane. This exception would be brought about by the more restrained and planar pen-tene ring, compared with other larger cyclic nonplanar olefins in Table VI, but the exact reason is not yet known. Linear inner olefin, 2-octene, is oxidized to both 2- and 3-octanones. 2-Methyl-2-butene is oxidized to 3-methyl-2-butanone, while ethyl vinyl ether is oxidized to acetaldehyde and ethyl alcohol. These products were identified by NMR, but could not be quantitatively determined because of the existence of overlapping small peaks in the GC chart. The last reaction corresponds to oxidative hydrolysis of ethyl vinyl ether. Those olefins having bulky (a-methylstyrene, j8-methylstyrene, and allylbenzene) or electon-withdrawing substituents (1-bromo-l-propene, 1-chloro-l-pro-pene, fumalonitrile, acrylonitrile, and methylacrylate) are not oxidized. 

However, styrene and cyclohexene gave complex product mixtures, and 1-octene did not react under the same reaction conditions. Thus, the activity of this catalyst is intrinsically low. Jacobs and co-workers [159,160] applied Veturello s catalyst [PO WCKOj ]3- (tethered on a commercial nitrate-form resin with alkylammonium cations) to the epoxidation of allylic alcohols and terpenes. The regio- and diastereoselectivity of the parent homogeneous catalysts were preserved in the supported catalyst. For bulky alkenes, the reactivity of the POM catalyst was superior to that of Ti-based catalysts with large pore sizes such as Ti-p and Ti-MCM-48. The catalytic activity of the recycled catalyst was completely maintained after several cycles and the filtrate was catalytically inactive, indicating that the observed catalysis is truly heterogeneous in nature. 

MFI Not given 1-Octene H2O2 Autoclave 45 °C 81% 91% epoxide 45 min rxn MeOH soln [134]... 

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]. 

Heptachloro-3a,4,7,7a-tetrahydro-4,7-methano-l/7-indene see Chlordane Heptachlor triol, see Heptachlor epoxide Heptanal, see Heptane. 1-Octene 1-Fleptanol. see Heptane Heptanoic acid, see Heptane 1-Fleptene. see Heptane Heptyl hydroperoxide, see Heptane Hexachlorobenzene, see Hexachlorobutadiene,... 

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