1-Decene oxidation

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 reaction is not stereospecific thus reduction of either cis- or trans-5-decene oxide gives a 4 1 mixture of trans- and cis-decene. ... 

DMAP = N,N-dimethylaminopyiidine, DMF = N -dimethylformamide, DCM = dichloromethane, PTAT = phenyltrimethylammonium tribromide, EO = ethylene oxide, PO = propylene oxide, ECH = epichlrohydrin, SO = styreneoxide, AGH = allylicglycidil ether. BO = butylene oxide, HO = n-hexene oxide, DO = N-decene oxide, PPO = 2-phenylpropylene oxide, PS-DFILX = polymer supported diol functionalized ionic liquids, acac = acetyl acetonate, CIL= carboxylic-acid functionalized imidazolium-based ILs, note active site consideration for TOP calculation is not uniform. Co-valent triazine complexes... 

In contrast to oxidation in water, it has been found that 1-alkenes are directly oxidized with molecular oxygen in anhydrous, aprotic solvents, when a catalyst system of PdCl2(MeCN)2 and CuCl is used together with HMPA. In the absence of HMPA, no reaction takes place(100]. In the oxidation of 1-decene, the Oj uptake correlates with the amount of 2-decanone formed, and up to 0.5 mol of O2 is consumed for the production of 1 mol of the ketone. This result shows that both O atoms of molecular oxygen are incorporated into the product, and a bimetallic Pd(II) hydroperoxide coupled with a Cu salt is involved in oxidation of this type, and that the well known redox catalysis of PdXi and CuX is not always operalive[10 ]. The oxidation under anhydrous conditions is unique in terms of the regioselective formation of aldehyde 59 from X-allyl-A -methylbenzamide (58), whereas the use of aqueous DME results in the predominant formation of the methyl ketone 60. Similar results are obtained with allylic acetates and allylic carbonates[102]. The complete reversal of the regioselectivity in PdCli-catalyzed oxidation of alkenes is remarkable. 

With this as introduction, let us now look at the individual steps in more detail for the case of hydroboration-oxidation of 1-decene. A boron hydride that is often used is dibomne (B2H6). Diborane adds to 1-decene to give tridecylborane according to the balanced equation ... 

Spudich, J., and Hastings, J. W. (1963). Inhibition of the bioluminescent oxidation of reduced flavin mononucleotide by 2-decenal./. Biol. Chem. 238 3106-3108. 

Another recent patent (22) and related patent application (31) cover incorporation and use of many active metals into Si-TUD-1. Some active materials were incorporated simultaneously (e.g., NiW, NiMo, and Ga/Zn/Sn). The various catalysts have been used for many organic reactions [TUD-1 variants are shown in brackets] Alkylation of naphthalene with 1-hexadecene [Al-Si] Friedel-Crafts benzylation of benzene [Fe-Si, Ga-Si, Sn-Si and Ti-Si, see apphcation 2 above] oligomerization of 1-decene [Al-Si] selective oxidation of ethylbenzene to acetophenone [Cr-Si, Mo-Si] and selective oxidation of cyclohexanol to cyclohexanone [Mo-Si], A dehydrogenation process (32) has been described using an immobilized pincer catalyst on a TUD-1 substrate. Previously these catalysts were homogeneous, which often caused problems in separation and recycle. Several other reactions were described, including acylation, hydrogenation, and ammoxidation. 

Cyclic stannanes can be generated by reaction of stannylenes with alkynes112. For example, bis[bis(trimethylsilyl)methyl]tin reacts with cyclooctyne to provide A1,18-9,10-(distanna-9,9,10,10-tetrakis[bis(trimethylsilyl)methyl])bicyclo[6,2,0]-decene, 69. This reaction is a typical oxidative addition on stannylenes. 

The metal-catalysed autoxidation of alkenes to produce ketones (Wacker reaction) is promoted by the presence of quaternary ammonium salts [14]. For example, using copper(II) chloride and palladium(II) chloride in benzene in the presence of cetyltrimethylammonium bromide, 1-decene is converted into 2-decanone (73%), 1,7-octadiene into 2,7-octadione (77%) and vinylcyclohexane into cyclo-hexylethanone (22%). Benzyltriethylammonium chloride and tetra-n-butylammo-nium hydrogen sulphate are ineffective catalysts. It has been suggested that the process is not micellar, although the catalysts have the characteristics of those which produce micelles. The Wacker reaction is also catalysed by rhodium and ruthenium salts in the presence of a quaternary ammonium salt. Generally, however, the yields are lower than those obtained using the palladium catalyst and, frequently, several oxidation products are obtained from each reaction [15]. 

Similar results were obtained in the biphasic Wacker oxidation of 1-decene, catalyzed by PdS04, CUSO4 and a heteropolyacid H9PV6M06O40 in the presence of chemically modified p-cyclodextrins (methyl, methoxy, hydroxypropyl derivatives). The reactions yielded 2-decanone in rather high yield (up to 58 %) accompanied by extensive isomerization of 1-decene to internal decenes. Nevertheless, these latter apparently did not react, since the ratio of 2-decanone among the oxodecenes exceeded 99 % (Scheme 10.12). 

It was also reported by PruP et al. [31] that in situ formed cobalt(III) complexes of pyridine-4-ylmethyl-propyl-amine (PYPA) on preformed organomodified HMS are active as catalysts in the aerobic oxidation of styrene and also 1-decene (Figure 3). Incorporation of PYPA may be achieved by following several routes viz. sol-gel synthesis, post modification of sol-gel AMP-HMS, and grafting. The authors proposed that all materials are able to act as... 

These palladium-functionalized dendrimers show selectivity for the linear reaction product. A drop in activity was found when the catalysts were reused (1-decene as substrate/G(4)Pd(PPh3)2 dendrimer as catalyst 92, 75, 73, and 45% yield for the first, second, third, and fourth, respectively). The (dba)Pd-PPh2-PAMAM-Si02 dendrimers of generations 0—4 showed activity for the oxidation of terminal alkenes under mild conditions. The catalytic activity was found to be dependent on... 

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. 

Since then, a number of studies of model systems have confirmed that dialkenes, cyclic alkenes, and aromatics form substituted monocarboxylic acids, dicar-boxylic acids, and organic nitrates in the condensed phase (e.g., see O Brien et al., 1975a Grosjean and Friedlander, 1979 Dumdei and O Brien, 1984 Izumi and Fukuyama, 1990 and Forstner et al., 1997a, 1997b). For example, Table 9.21 shows the products identified in particles formed in the 1-octene- and 1-decene-NO,-ambient air systems. In both bases, only 40% of the total particle mass could be identified, and the yields shown in Table 9.21 are those relative to the total identified compounds. That is, the absolute product yields are about factor of 2.5 larger. As expected from the known oxidation mechanisms (see Chapter 6.E), heptanal and heptanoic acid are the major condensed-phase oxidation products of 1-octene and nonanal and nonanoic acid from 1-decene (see Problem 4). The mechanism of formation of the fura-nones, which are formed in relatively high yields, is not... 

TABLE 9.21 Major Products Observed in the Particles Formed in the VOC - NO, Oxidations in Air of 1-Octene and l-Decene"... 

In smog chamber studies of the oxidation of 1-decene, octanal was the condensed-phase product formed in the next highest yield after nonanal, nonanoic acid, and dihydro-5-pentyl-2(3//)furanone (Forstner et al., 1997a). Write a plausible mechanism for its formation. 

NonenaL 2-decenal and 2-undecenal were concentrated appreciably in fraction FI of the 207 bar/50°C extract, whereas aldehydes associated with lipid oxidation such as pentanaL hexanal and octanal were not concentrated by the extraction method used, probably because these constituents continue to accumulate following extraction or because low volatiles are not extracted well by the SC-COj method used. 

Some synthetically useful oxidations of alkenes by permanganate can be performed under controlled conditions. For example, 1-decene could be oxidized to nonanoic acid in 91% yield by permanganate in the presence of the phase-transfer agent Aliquat 336.319 In a benzene solution with crown ether and permanganate, a-pinene is oxidized to cis-pinonic acid in 90% yield (equation 110).314... 

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