Reaction of olefin oxidations

Glycol ethers can be prepared from isopropyl alcohol by reaction of olefin oxides, eg, ethylene oxide [75-21-8] (qv) or propylene oxide [75-56-9] (qv). Reactions such as that to produce 2-isoproxyethanol [109-59-1] (isopropyl CeUosolve) are generally cataly2ed by an alkaU hydroxide. 

Reaction of olefin oxides (epoxides) to produce poly(oxyalkylene) ether derivatives is the etherification of polyols of greatest commercial importance. Epoxides used include ethylene oxide, propylene oxide, and epichl orohydrin. The products of oxyalkylation have the same number of hydroxyl groups per mole as the starting polyol. Examples include the poly(oxypropylene) ethers of sorbitol (130) and lactitol (131), usually formed in the presence of an alkaline catalyst such as potassium hydroxide. Reaction of epichl orohydrin and isosorbide leads to the bisglycidyl ether (132). A polysubstituted carboxyethyl ether of mannitol has been obtained by the interaction of mannitol with acrylonitrile followed by hydrolysis of the intermediate cyanoethyl ether (133). 

Epoxide Yields in Reactions of Olefins Oxidation by sec-Decylsulfonic Peracid [40]... 

The most common method of epoxidation is the reaction of olefins with per-acids. For over twenty years, perbenzoic acid and monoperphthalic acid have been the most frequently used reagents. Recently, m-chloroperbenzoic acid has proved to be an equally efficient reagent which is commercially available (Aldrich Chemicals). The general electrophilic addition mechanism of the peracid-olefin reaction is currently believed to involve either an intra-molecularly bonded spiro species (1) or a 1,3-dipolar adduct of a carbonyl oxide, cf. (2). The electrophilic addition reaction is sensitive to steric effects. 

The reactions of olefins with peracids to form epoxides allows for the selective oxidation of carbon-carbon double bonds in the presence of other functional groups which may be subject to oxidation (for example, hydroxyl groups). The epoxides that result are easily cleaved by strong acids to diols or half-esters of diols and are therefore useful intermediates in the synthesis of polyfunctional compounds. 

Finally, obtaining olefin 93 from the reaction of thiirene oxide 18a with two equivalents of phenylmagnesium bromide may be a consequence of the initial nucleophilic Michael-type addition of the latter across the carbon carbon double bond of the cyclic sulfone22 (see equation 31). 

Fe-Catalyzed Oxidation Reactions of Olefins, Alkanes, and Alcohols Involvement of Oxo- and Peroxo Complexes... 

TABLE 15. Reaction of benzenesulfonylcarbonitrile oxide with olefins ... 

The complex Ni[(S2C2(CF3)2)]2 (392) is able to bind light olefins selectively and reversibly.1081 According to Scheme 4, the reaction of olefins with (392) can be controlled electrochemically, where the oxidation state-dependent binding and release of olefins is fast on the electrochemical timescale. Olefin binding is supposed to occur via the ligand S-donors. 

Pd2+ salts are useful reagents for oxidation reactions of olefins. Formation of acetaldehyde from ethylene is the typical example. Another reaction is the formation of vinyl acetate by the reaction of ethylene with acetic acid (16, 17). The reaction of acetic acid with butadiene in the presence of PdCl2 and disodium hydrogen phosphate to give butadienyl acetate was briefly reported by Stem and Spector (110). However, 1-acetoxy-2-butene (49) and 3-acetoxy-l-butene (50) were obtained by Ishii and co-workers (111) by simple 1,2- and 1,4-additions using PdCl2/CuCl2 in acetic acid-water (9 1). 

The reaction of olefin epoxidation by peracids was discovered by Prilezhaev [235]. The first observation concerning catalytic olefin epoxidation was made in 1950 by Hawkins [236]. He discovered oxide formation from cyclohexene and 1-octane during the decomposition of cumyl hydroperoxide in the medium of these hydrocarbons in the presence of vanadium pentaoxide. From 1963 to 1965, the Halcon Co. developed and patented the process of preparation of propylene oxide and styrene from propylene and ethylbenzene in which the key stage is the catalytic epoxidation of propylene by ethylbenzene hydroperoxide [237,238]. In 1965, Indictor and Brill [239] published studies on the epoxidation of several olefins by 1,1-dimethylethyl hydroperoxide catalyzed by acetylacetonates of several metals. They observed the high yield of oxide (close to 100% with respect to hydroperoxide) for catalysis by molybdenum, vanadium, and chromium acetylacetonates. The low yield of oxide (15-28%) was observed in the case of catalysis by manganese, cobalt, iron, and copper acetylacetonates. The further studies showed that molybdenum, vanadium, and... 

The major breakthrough in the catalytic asymmetric dihydroxylation reactions of olefins was reported by Jacobsen et al.55 in 1988. Combining 9-acetoxy dihydroquinidine as the chiral auxiliary with /V-methylmorphine TV-oxide as the secondary oxidant in aqueous acetone produced optically active diols in excellent yields, along with efficient catalytic turnover. 

Vargaftik, M.N. et al., Giant Pd clusters as catalysts of oxidative reactions of olefins and alcohols, J. 

Figure 1.. The two proposed reaction pathways based on experimental results for hydroboration reactions of olefins catalyzed by the Wilkinson catalyst. (O.A. Oxidative Addition Olefin Migratory Insertion R.E. Reductive Elimination)...

On the other hand, reactions of nitrile oxides with 1,2-disubstituted olefins are slower and regioselectivity usually was not so high. For example, benzonitrile oxides, obtained from the corresponding chlorooximes 167, undergo 1,3-dipolar cycloaddition reaction with methyl cinnamate to produce the 5-phenyl 168 and 4-phenyl 169 regioisomers in approximately an 80 20 ratio °. However, use of A,iV-diethylcinnamamide as the dipolarophile... 

Other Reactions of Olefinic Steroids.—Reaction of cholest-5-en-3-one with air and acetic acid shows that isomerization to the A -3-oxo-compound is accompanied by autoxidation to the 6a- and 6/8-hydroxy-3-oxo-A -compounds and the 3,6-dioxo-A -compound. The oxidation appears to be controlled by heterolysis of the 4/3-proton and formation of the intermediate ion pair (73). Sitosterol was autoxi-dized at C-7 to give the 7-oxo- and the epimeric 7-hydroxy-derivatives. Oxidation of a 17-methylene steroid with Pb, Tl" , and Hg acetates in methanol gave a wide variety of products. The reaction with Pb(OAc)4 gave the rearranged products (74), (75), and (76) whereas the Tl and Hg products retained the... 

This review deals with the recent developments in the transition metal-catalyzed carbonylation reaction, especially hydroformylation, hydrocarbonylation, and oxidative hydrocarbonylation reactions of olefins, referring to literature since 1994. Because of the importance of carbonyl functionality in organic chemistry and the ideal atom efficiency of... 

An unanticipated catalytic reaction of olefinic hydrocarbons was described in 1964 by Banks and Bailey.1 2 They discovered that C3-C8 alkenes disproportionate to homologs of higher and lower molecular weight in the presence of alumina-supported molybdenum oxide [Eq. (12.1)], cobalt oxide-molybdenum oxide, molybdenum hexacarbonyl, or tungsten hexacarbonyl at 100-200°C, under about 30 atm pressure ... 

Oxidation of 2-Butene with Selenium Dioxide. The stoichiometry of the reaction of 2-butene with selenium dioxide shows that approximately 0.85 mole of l-acetoxy-2-butene plus 0.85 mole of bis(l-methyl-2-acetoxypropyl) selenide are produced per mole of selenium dioxide consumed. This suggests that, at least for this particular group of olefins, in the mechanism of olefin oxidation with selenium dioxide the formation of selenides should be considered as the final reduced state of the oxidant rather than elemental selenium. 

Reactions. Oxidations. Nucleophilic Reactions of Olefins. These reactions, which over-all, involve replacement of vinyllic hydride by a nucleophile (Reaction 1),... 

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