2- octanol, oxidation

The 3.8-nonadienoate 91, obtained by dimerization-carbonylation, has been converted into several natural products. The synthesis of brevicomin is described in Chapter 3, Section 2.3. Another royal jelly acid [2-decenedioic acid (149)] was prepared by cobalt carbonyl-catalyzed carbonylation of the terminal double bond, followed by isomerization of the double bond to the conjugated position to afford 149[122], Hexadecane-2,15-dione (150) can be prepared by Pd-catalyzed oxidation of the terminal double bond, hydrogenation of the internal double bond, and coupling by Kolbe electrolysis. Aldol condensation mediated by an organoaluminum reagent gave the unsaturated cyclic ketone 151 in 65% yield. Finally, the reduction of 151 afforded muscone (152)[123]. n-Octanol is produced commercially as described beforc[32]. 

The by-product of this process, pelargonic acid [112-05-0] is also an item of commerce. The usual source of sebacic acid [111-20-6] for nylon-6,10 [9008-66-6] is also from a natural product, ticinoleic acid [141-22-0] (12-hydroxyoleic acid), isolated from castor oil [8001-79-4]. The acid reacts with excess sodium or potassium hydroxide at high temperatures (250—275°C) to produce sebacic acid and 2-octanol [123-96-6] (166) by cleavage at the 9,10-unsaturated position. The manufacture of dodecanedioic acid [693-23-2] for nylon-6,12 begins with the catalytic trimerization of butadiene to make cyclododecatriene [4904-61-4] followed by reduction to cyclododecane [294-62-2] (see Butadiene). The cyclododecane is oxidatively cleaved to dodecanedioic acid in a process similar to that used in adipic acid production. 

Peroxytnfluoroacetic acid is used tor numerous oxidations of saturated hydrocarbons and aromatic compounds It oxidizes alkanes, alkanols, and carboxylic acids with formation of hydroxylation products [29] Oxidation of cyclohexane with peroxytnfluoroacetic acid proceeds at room temperature and leads to cyclohexyl trifluoroacetate in 75% yield, 1-octanol under similar conditions gives a mixture of isomeric octanediols in 59% yield, and palmitic acid gives a mixture of hydroxypalmitic acids in 70% yield [29]... 

A solution of 50 g of 1 -azabicyclo [2.2.2] -3-octanone hydrochloride in 200 cc of water was hydrogenated at room temperature and 50 atm pressure with 1 g of platinum oxide as catalyst. After the calculated amount of hydrogen had been absorbed, the mixture was filtered and concentrated in vacuo to dryness. The residual product was recrystallized from a mixture of methanol and acetone and formed prisms melting above 300°C. It was identified as 1 -ezabicy-clo[2.2.2] -3-octanol hydrochloride. 

Octanal has been prepared by the reduction of caprylonitrile with hydrogen chloride and stannous chloride,2 by the passage of a mixture of caprylic acid and formic acid over titanium dioxide3 or manganous oxide,4 by dehydrogenation of 1-octanol over copper,6 and by oxidation of 1-octanol.6... 

Table 62. Typical purity of tantalum and niobium oxides prepared from strip solutions after extraction with 2-octanol. Impurity level is given in ppm.

Stability of 2,3,7,8-Tetrachlorodibenzo- >-dioxin Towards Air Oxidation Under Simulated Conditions. Air was bubbled through two borosilicate glass gas absorption bottles equipped with fritted glass bubblers. The first bottle contained 1-octanol for presaturation of the air, and the second bottle contained 1-octanol solutions of the dioxin treated as follows (1) octanol only, (2) octanol mixed with 74-105ju, glass beads to increase the surface area, and (3) octanol mixed with magnesium oxide to simulate a basic soil. The original solution and the sample solutions were scanned with a UV spectrophotometer at various time intervals for 4 days to determine the stability of 2,3,7,8-tetrachlorodibenzo-p-dioxin. 

Under microwave irradiation and applying MCM-41-immobilized nano-iron oxide higher activity is observed [148]. In this case also, primary aliphatic alcohols could be oxidized. The TON for the selective oxidation of 1-octanol to 1-octanal reached to 46 with 99% selectivity. Hou and coworkers reported in 2006 an iron coordination polymer [Fe(fcz)2Cl2]-2CH30H with fez = l-(2,4-difluorophenyl)-l,l-bis[(l//-l,2,4-triazol-l-yl)methyl]ethanol which catalyzed the oxidation of benzyl alcohol to benzaldehyde with hydrogen peroxide as oxidant in 87% yield and up to 100% selectivity [149]. An alternative approach is based on the use of heteropoly acids, whereby the incorporation of vanadium and iron into a molybdo-phosphoric acid catalyst led to high yields for the oxidation of various alcohols (up to 94%) with molecular oxygen [150]. 

The product is 2,7-octadien-l-oI which can be dehydrogenated/hydrogenated internally to give 7-octenal, which can be hydroformylated to the dialdehyde, nonadialdehyde, and then hydrogenated to nonadiol. The initial product can be hydrogenated to 1-octanol the dialdehyde can be oxidized to the diacid. The catalyst used is Pd modified with the Li salt of monosulphonated triphenylphosphine. 

FIG. 25 (a) Schematic representation for a photocatalytic mechanism based on shuttle photosensitizers at liquid-liquid interfaces. (Reprinted with permission from Ref. 182. Cop5right 1999 American Chemical Society.) (b) This mechanism is compared to the photo-oxidation of 1-octanol by the heterodimer ZnTPPS-ZnTMPyP in the presence of the redox mediator ZnTPP. (From Ref. 185.)... 

Figure 1 Selective oxidation of 1-octanol, 2-octanol and geraniol to the...

The effect of Bi promotion for the selective oxidation of 1-octanol using H202 as oxidant is reported in Table 2. Since decomposition of H202 by Platinum Group Metals is rapid, H202 is fed continuously into the reactor over 2 hours. The results obtained demonstrate that the presence of Bi203 as an additive within the reaction mixture displays no significant influence on catalyst activity. However, Bi promoted Pt/C catalysts, prepared by co-precipitation of... 

Table 2 Selective oxidation of 1-octanol using H202 as oxidant. Conditions 0.015mol 1-octanol in toluene, reactant metal molar ratio 80 1, 60°C, 600rpm, 30%H2O2 fed at rate of 1 molar equivalent/h, atmospheric pressure.

Table 3 indicates that 5%Pt,l%Bi/C is active for three reaction cycles in the selective oxidation of the chosen alcohols. For primary alcohols the use of water as solvent can promote the aldehyde to carboxylic acid reaction (3). This effect is observed in the selective oxidation of 1-octanol where octanoic acid is formed with 97% selectivity in the first cycle dropping to 81% in the third. In the selective oxidation of geraniol only citral is observed as the oxidation product. The presence of the double bond stabilises the aldehyde even in the presence of... 

There is considerable interest in synthesizing copolymers. This is actually possible if organisms are confronted with mixtures of so-called related and unrelated substrates. Copolymers can also be synthesized from unrelated substrates, e.g., from glucose and gluconate. The 3-hydroxydecanoate involved in the polyester is formed by diversion of intermediates from de novo fatty-acid synthesis [41,42]. Related , in this context, refers to substrates for which the monomer in the polymer is always of equal carbon chain length to that of the substrate offered. Starting from related substrates, the synthesis pathway is closely connected to the fatty-acid /1-oxidation cycle [43]. In Pseudomonas oleovor-ans, for example, cultivated on octane, octanol, or octanoic acid, the synthesized medium chain length polyester consists of a major fraction of 3-hydroxyoc-tanoic acid and a minor fraction of 3-hydroxyhexanoic acid. If P. oleovorans is cultivated on nonane, nonanol, or nonanoic acid, the accumulated polyester comprises mainly of 3-hydroxynonanoate [44]. 

The chemical composition of B. papyrifera olibanum is markedly different from that of other Boswellia, with small amounts of monoterpenes and sesquiterpenes, large amounts of w-octanol (18) and -octy I acetate (40), with the latter being the major compound, and the presence of particular diterpenes [incensole (127), incen-sole acetate (129), incensole oxide (130) and incensole oxide acetate (131)] and the absence of both isoincensole and isoincensole acetate (128). Linear carboxylic acids from hexanoic acid (10) to lauric acid (93) were also identified in B. papyrifera olibanum exclusively. 

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