CCOC(CCC(C)=O)=O.CC1(CCCCCCCC)OC(=O)CC1.Cl.Cl[C:28]([CH3:43])([CH2:35][CH2:36][CH2:37][CH2:38][CH2:39][CH2:40][CH2:41][CH3:42])[CH2:29][CH2:30][C:31]([O:33][CH3:34])=[O:32]>CCOCC>[CH3:43][CH:28]([CH2:35][CH2:36][CH2:37][CH2:38][CH2:39][CH2:40][CH2:41][CH3:42])[CH2:29][CH2:30][C:31]([O:33][CH3:34])=[O:32]
An ether solution of the Grignard compound obtained from n-chlorooctane is added dropwise, under nitrogen, to a solution of ethyl levulate in ether, cooled to 0° C. The resulting lactone, 5-methyl-5-octyltetrahydrofuran-2-one (II), is converted with methanolic hydrochloric acid to methyl 4-chloro-4-methyldodecanoate (III), which, after eliminating hydrochloric acid by heating and then carrying out hydrogenation, gives racemic methyl 4-methyldodecanoate (IV), from which 4-methyldodecanoic acid (V) is obtained by hydrolysis. At the same time, the tosylate is prepared from 2-hexanol and, when reacted with sodium malonate in ethanolic solution, forms ethyl 2-carbethoxy-3-methylheptanoate (VI). This is converted to racemic 3-methylheptanoic acid (VII) by hydrolysis and thermal decarboxylation.
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