Pentanoic acid, ozonation

An independent proof of this finding was recently obtained by Ciardelli, Benedetti, Pieroni and Pino (23, 24) who prepared an atactic poly-(S)-4-xnethyl-1-hexene having [M] >5 = +190 from a poly-(S)-4-methyl-l-hexyne having an optical purity of about 89.5% as demonstrated by the optical purity of (S)-3-methyl-pentanoic acid obtained by ozonization of the unsaturated polymer. The rotatory power of the polymer thus prepared is very near to the rotatory power of the non crystallizable poly-(S)-4-methyl-l-hexene obtained from a monomer having a 93% optical purity (see Table 8). 

Masten et al. (1996) investigated the oxidation of chlorinated benzenes such as 1,2-dichlorobenzene (1,2-DCB), 1,3,5-trichlorobenzene (1,3,5-TCB), and pentanoic acid (PA). TCB is often generated as a by-product of pesticide manufacturing, while DCB is commonly manufactured as an insecticide or a fumigant for industrial odor control. Due to their resistance to biological treatments, PA is usually nonreactive with ozone but can react with hydroxyl radicals (Masten et al., 1996). 

As a check of a possible reaction pathway for the formation of the shorter acids during ozonation of n-alkylmercurials, pentanoic acid was ozonized for 4 hours at 10 °C. The ozonation was carried out in dichloro-... 

Octanone 1-Octene Octyl mercaptan 1-Octyne Oxalic acid Oxygen Ozone Pentadecane Pentanal Pentane Pentanoic acid... 

A methanolic soln. of the startg. enone ozonized at -60° until 1.1 equivalents ozone have been added, after N -f lushing NaBH4 added portion wise at 0° over 1 hr. intervals, and stirred overnight at room temp. -> 5-hydroxy-3,3-dimethyl-pentanoic acid <5-lactone. Y 58%. F. e. s. C. G. Chavdarian and C. H. Heathcock, J. Org. Chem. 40, 2970 (1975). 

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