Cyclododecanone from cyclododecanol

More reactive hydroperoxides can be converted selectively to alcohols via the method of Bashkirov (Fig. 4.44), where a boric acid ester protects the product from further oxidation and thus increases the selectivity [121]. The method is used to convert C10-C20 paraffins to alcohols which are used as detergents and surfactants, for the oxidation of cyclohexane (see elsewhere) and cyclododecane to cyclododecanol (cyclododecanone) for the manufacture of nylon-12. 

The CDT is then hydrogenated and further oxidized at 150°C to cyclododecanol and cyclododecanone with oxygen from the air. In this reaction, up to 5% ketone hydroperoxide occurs, which can be decomposed to form cyclododecanol, cyclododecanone, and dicarboxylic acid. These undesired reactions can be prevented by adding boric acid, which is present as polyboric acid at this temperature. The peroxide probably forms an adduct with the polyboric acid, and the course of this reaction is not yet fully understood. The cyclododecanone is changed to lauryl lactam via the oxime in the usual way (cf. nylon 6). 

Nylon-12. Laurolactam [947-04-6] is the usual commercial monomer for nylon-12 [24937-16-4] manufacture. Its production begins with the mixture of cyclododecanol and cyclododecanone which is formed in the production of dodecanedioic acid starting from butadiene. The mixture is then converted quantitatively to cyclododecanone via dehydrogenation of the alcohol at 230—245°C and atmospheric pressure. The conversion to the lactam by the rearrangement of the oxime is similar to that for caprolactam manufacture. There are several other, less widely used commercial routes to laurolactam (171). 

Nylon 12 first beeame available on a semieommercial scale in 1963. The monomer, dodecanelactam, is prepared from butadiene by a multistaged reaction. In one proeess butadiene is treated with a Ziegler-type eatalyst system to yield the cyclic trimer, cyclododeca-1, 5, 9-triene. This may then be hydrogenated to give cyelododeeane, which is then subjeeted to direct air oxidation to give a mixture of cyclododecanol and cyclododecanone. Treatment of the mixture with... 

Di-t-butyl chromate and its pyridine adduct are suitable for large-scale oxidations of alcohols to ketones, thus cyclododecanol was converted into cyclododecanone (97 Alcohols are easily separated from non-hydroxylic compounds via their calcium chloride complexes. This method was used to separate cyclododecanone and cyclododecanol and is suitable for the separation of large quantities of material." All-cis-cyclododecane-l,5,9-triol was converted into the all-cis-tri-amine by tosylation, azide substitution, and reduction, and the amine acylated with 2,3-dimethoxybenzoyl chloride to give the tri-amide, an analogue of enterochelin. ... 

Sodium bromate in presence of CAN or CAS is an effective reagent for the oxidation of secondary alcohols into the corresponding ketones (Tomioka et al., 1982 Kanemoto et al., 1986). For instance cyclododecanol is oxidized in 98% yield to cyclododecanone, and bor-neol is oxidized in 77% yield into camphor. Primary alcohols are not affected, so that this is a useful methodology for the oxidation of secondary alcohols in presence of primary ones. The presence of a double bond in the substrate, even at a position far way from the sec-... 

Dodecanedioic acid is prepared from cyclododecene (obtained from butadiene) by methods which are entirely analogous to those used to prepare adipic acid from benzene (section 10.2.2(a)). The cyclododecene is reduced to cyclododecane, which is oxidized firstly to a mixture of cyclododecanol and cyclododecanone and then to dodecanedioic acid. Dodecanedioic acid is a colourless crystalline solid, m.p. 129°C. 

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