Carbon—oxygen double bond INDEX

Examination of the molecular formula C14H2602 reveals that the compound has an index of hydrogen deficiency of 2. Because we are told that the compound is a carboxylic acid, one of these elements of unsaturation must be a carbon-oxygen double bond. The other must be a carbon-carbon double bond because the compound undergoes cleavage on ozonolysis. Examining the products of ozonol-ysis serves to locate the position of the double bond. 

Compound A (C4H602) has an index of hydrogen deficiency of 2. With two oxygen atoms and a peak in the infrared at 1760 cm-1, it is likely that one of the elements of unsaturation is the carbon-oxygen double bond of an ester. The H NMR spectrum contains a three-proton singlet at 8 2.1 ppm, which is consistent with a CH3C unit. It is likely that compound A is an acetate ester. 

A compound C3H6O2 has an index of hydrogen deficiency of 1. Thus, it could possess a carbon-carbon double bond, a carbon-oxygen double bond, or a ring. 

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