1-Decene epoxidation

Nugent and RajanBabu described that with Cp2TiCl , that had been isolated and purified prior to use, an (E) to (Z) ratio of 3-4 1 of 5-decenes was observed from either cis- or trans-5-decene oxide [28,29]. Therefore, it seems clear that a common long-lived /f-lilanoxy radical intermediate was formed from both epoxides. After further reduction and elimination the formation of the mixture of olefin diastereoisomers was observed. 

The catalytic potential of the MTO/UHP oxidation system has also been tested in the room-temperature ionic liquid [EMIM] [BF4], in which it is soluble [77]. In contrast, the olefin is poorly soluble in such solvenfs. Therefore, the whole system is biphasic. Excellent conversions and selectivities for the epoxides of a wide number of olefinic substrates were reached under these anhydrous conditions. The exception was 1-decene (data collected in Table 17), for which poor conversion (entry 9, Table 17) may result in phase transfer problems, since it is the least soluble substrate in the ionic liquid. 

Styrene and 1-decene are selectively epoxidized, as shown in Table XXVII (293). The rates observed for PWM-Co are greater than those observed for Ni(dmp)2 and Fe(dmp)3, and the selectivities are comparable or higher for the former (295). It is also remarkable that PWn—Co polyanion exhibits a steric effect comparable to that of a moderately hindered TTMPP ligand in the... 

In the synthesis of an epoxide from an alkene with TBHP/Mo, the stereochemistry of the alkene is retained in the epoxide. It has been suggested that the reaction proceeds through the transition state (124). ° 1-Decene and the alkene (115) (see equation 42) have been epoxidized with TBHP/Mo (equations 45 and 46). The epoxidation of (115) is regio- as well as stereo-selective the reagent approaches the electron-rich double bond from the less hindered face. 

Hydrocarboxylation of the Ce-Cs a-olefins with cobaltcarbonyl/pyridine catalysts at 200 °C and 20 MPa gives predominantly the linear carboxylic acids. The acids and their esters are used as additives for lubricants. The Ce-Cio a-olefins are hydroformylated to odd-numbered linear primary alcohols, which are converted to polyvinylchloride (PVC) plasticizers with phthalic anhydride. Oligomerization of (preferably) 1 -decene, applying BF3 catalysts, gives oligomers used as synthetic lubricants known as poly-a-olefins (PAO) or synthetic hydrocarbons (SHC) [11, 12]. The C10-C12 a-olefins can be epoxidized by peracids this opens up a route to bifunctional derivatives or ethoxylates as nonionic surfactants [13]. 

Thus, the addition of pyridine led to certain improvement in terms of rate and selectivity for epoxide formation, at the expense of catalyst lifetime. This turned out to be a minor problem for highly reactive substrates such as tetra-, tri- and c/5-di-substituted alkenes, but not for less electron rich substrates such as terminal alkenes. Using the pyridine (12 mol%) conditions did not fully convert either 1-decene or styrene even after prolonged reaction times. 

We have studied the epoxidation of 1-decene in different solvents, in order to optimize reaction conditions. A marked solvent effect was foimd, as reported in Table 6.4. Acetonitrile seemed to be the best solvent. 

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. 

Indeed, one of the most toxic known breakdown products of hpid peroxidation to cells is trans, trans, 2,4, decadienal epoxide (DDE). This product reacts with both dAdo and dGuo, via the formation of a 4,5-epoxy-2(E)-decenal, to yield two highly mutagenic lesions, lN -etheno-2 -dAdo and 1 etheno2-dGuo [54,67,68]. 

Further work by Wynberg and coworkers was aimed at even increasing the yield of 1,2-epoxyoctane using an optimized two-phase system and a cell renewal procedure11191. Thus, yields up to 150 mg 1,2-epoxyoctane per mL 1-octene and up to 20-25 mg 1,2-epoxyoctane per mL culture was obtained. Some other substrates were tested in this optimized system. Of these, 1-decene was converted into (R)-l,2-epox-ydecane (60 % o. p.), while allylbenzene was converted to the corresponding epoxide. However, no effort was made to determine the absolute configuration and the optical purity of this product. 

The methatesis of vegetable oils with ethylene is a very interesting way to obtain new unsaturated structures to be transformed into new polyols via the epoxidation - alcoholysis route. Trioleine was used as a model compound (the triester of glycerol with oleic acid), the methatesis reaction with ethylene being catalysed by a special ruthenium catalyst [72]. The resulting triglyceride, with terminal double bonds, after removal of the 1-decene formed, is transformed into polyols by epoxidation, followed by alcoholysis with methanol (reactions 17.27 and 17.28). 

Reaction of alkenes with tert-butyl hydroperoxide (t-BuOOH) in the presence of a transition metal catalyst, for example, a vanadium(V), molybdenum(VI) or titanium(IV) complex, provides an excellent method for the preparation of epoxides. The molybdenum catalysts are most effective for the epoxidation of isolated double bonds, and the vanadium or titanium catalysts are most effective for aUylic alcohols. Even terminal alkenes can be epoxidized readily. For example, 1-decene was converted into its epoxide with t-BuOOH and Mo(CO)6 on heating in 1,2-dichloroethane. 

A fluorous medium has been utilized for alkcnc epoxidation employing the dioxirane derived from the fluoroketone 14, which is also effective in catalytic quantities with Oxone as the terminal oxidant. For example, treatment of tro w-4-decene (13) with 5 mol% of ketone 14 and 1.5 equiv of Oxone in a bicarbonate buffered water exanuoroisopropanol (HFIP) medium led to the quantitative formation of the corre.sponding epoxide 15 <01TL4463>. 

First, several aldehydes (reduclanis) were screened by taking the expoxidation of 2-methyl-2-decene catalyzed by Ni(dmp)2 (Table 6). In case of employing butyraldehyde, both conversion of olefin and yield of the epoxide were low. On the contrary, the corresponding... 

Table 6. Epoxidation of 2-methyl-2-decene by using several aldehyde...

The efficiency of nickel(II) complexes in the present epoxidation was demonstrated by taking epoxidation of 2-methyl-2-decene as a model reaction. Through the three experiments carried out in the presence of 4.0 mol%, 0.256 mol%, and 0.0096 mol% of Ni(dmp)2 against olefin, respectively (Table 9), it was found that, even in the case of employing only 0.0096 mol% of Ni(dmp)2, the epoxidation proceeded smoothly and the corresponding epoxide was obtained in 1020000% yield based on Ni(dmp)2. 

C12-14 alpha olefin C16-18 alpha olefin Decene-1 Tetradecene-1 epoxide source... 

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