Linear carboxylic acids

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. 

As in the case of the linear carboxylic acids, the principal by-products are water, C02 and the corresponding hydrocarbons. Substantial quantities of iso-butane are formed for example during iso-butyric acid homologation (see Experimental Section) while 2-methylpentane accompanies the formation of 2,2-dimethylvaleric acid during syngas treatment of 2-methylvaleric acid. 

A long-chain linear carboxylic acid. Some fatty acids are saturated, and others are unsaturated, (pp. 939, 951)... 

FIGURE 5 Anderson-Schulz-Flory distribution of the linear hydrocarbons, linear oxygenates (n-alcohols, n-aldehydes, and linear carboxylic acids), and methyl alkyl ketones formed in the Fischer-Tropsch synthesis on an iron-containing Fischer-Tropsch catalyst operating at a temperature of 498 K (plotted using log(lO)). 

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]. 

Addition of carbon monoxide and water to an alkene, i.e. hydrocarboxylation, is catalyzed by a variety of transition metal complexes, including [Ni(CO)4], [Co2(CO)s] and [HaPtClg]. Unfortunately this reaction usually leads to mixtures of products due to both metal-catalyzed alkene isomerization and the occurrence of Irath Markownikov and anti-Markownikov addition of the metal hydride intermediate to the alkene. The commercially available zirconium hydride [(C5Hs)2Zr(H)Cl] can be used as a stoichiometric reagent for conversion of alkenes to carboxylic acids under mild conditions (equation 23). In this case the reaction with linear alkenes gives exclusively terminal alkyl complexes even if the alkene double bond is internal. Insertion of CO followed by oxidative hydrolysis then leads to linear carboxylic acids in very good yield. 

Figure 4.4 Dependence of the yield in toluene acylation with linear carboxylic acids on the chain length in the presence of CeY.

C42H70O11, Mr 751.01, cryst., mp. 112.5-113.5 °C, [a]o -63 (C2H5OH), an ionophoric polyether antibiotic with a dispiroketal structure produced by Strep-tomyces albus it preferentially forms complexes with monovalent cations (Na ). S. is formed biosyntheti-cally on the polyketide pathway, cyclization in the linear carboxylic acid proceeds on the diene/diepox-ide pathway. The 20-deoxy derivative is also formed. S. is used against coccidiosis in poultry breeding and also has antiviral activity (HIV). LD50 (mouse p.o.) 50 mg/kg. 

Diacids.—Cyclic /3-keto-sulphides, which are easily prepared from the parent ketone, can be oxidized to the acetates (7), which on further oxidation with alkaline hydrogen peroxide undergo ring opening to aw-diacids (Scheme 4). Similar treatment of linear carboxylic acid esters, but using iodine in methanol in the final step, leads to a a-keto-ester ketals (8). 

Ca content, calcium salt of long chain, saturated, linear carboxylic acids (montanic... 

The polyoxymethylene composition includes the nucleating agent of 0.1 wt% to 3.0 wt%. The nucleating agent is a sodium salt or a calcium salt of montanic add and a sodium salt or a calcium salt of a long chain, linear carboxylic acid. For example, Licomont Cav 102, LicomontNav 101 or their combination from Clariant. ... 

The regioselective hydrocarboxylation of alkenes and methylenecycloalkanes to linear carboxylic acids was also achieved in good yields and selectivity by the use of oxalic acid (in place of formic add) as the source of hydrogen and carbon monoxide, with the catalytic system Pd(OAc)2-dppb-PPh3 at 150 C and 20 atm.t ... 

In 2002, Aggarwal et al. developed an efficient route to unsaturated carboxylic acid 44 by a palladium-catalyzed Heck cyclization/carbonylation cascade of vinylic bromide 43 [18a] (Scheme 6.9). By choosing the appropriate phosphine ligand and intensive optimization, the formation of linear carboxylic acid 45 and the direct Heck-type product can be restricted. Recently, the same group applied this cascade transformation as the key step to the total synthesis of avenaciolide [18bJ. 

We would obtain one linear carboxylic acid, one hydroxy acid, and one alcohol ... 

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