Dimethyl pimelate

Dimethyl-2-phenyl-4-aminopyrazolone, al 10 Dimethyl pimelate, d617... 

Dimethyl phosphite, d541 Dimethyl pimelate, d530 Dimethyl propanedioate, d545... 

Dimethyl Pimelate The next higher homologue, dimethyl pimelate, returns us to an odd number of methylene groups, hence to a first-order spectrum. (See dimethyl glutarate with three methylene groups in Section 3.11.2.2). 

Alicyclic ketones produce esters of a, (o-dicarboxylic acids (entries 5, 6). An example is cyclohexanone, which gives dimethyl pimelate. These compounds, used for the production of polyesters and polyamides, have traditionally been synthetized in industry by oxidation of alicyclic ketones (74). 

Interestingly ketones can be carbonylated. Reaction of cyclohexanone with CO in MeOH using PdCh and CuCb as catalysts under mild conditions afforded dimethyl pimelate (474) and methyl 6-chlorohexanoate (475) in good yields. Mechanism of the carbonylation is not clear. Dimethyl pimelate (474) is formed by methanolysis (retro-Dieckmann reaction) of methyl cyclohexanonecarboxylate (478) promoted by CuCF and acid. Methyl cyclohexanonecarboxylate (478) may be formed by methoxypalladation of the enolate 476 to form Pd enolate 477, followed by CO insertion. Chlorination of cyclohexanone with CuCl2 gives 2-chlorocyclohexanone 480 which is converted to 475 [197]. 

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