Compound A is acidic in reaction , having the molecular formula , `C_(4) H_(8) O_(3)` , is oxidized with mild oxidizing agents to give B which is unstable , syrupy substance , it easily produces `, C , C_(3) H_(6) O` and carbon dioxide . On heating A alone yields D , `C_(4) H_(6) O_(2)` an acid neutralization equivalent of 104 . what are A , B , C and D ? Give their structural formulae too.

Explanation

Compound A has molecular formula `C_(4) H_(8) O_(3)` as it acidic in reaction . So , it should have -COOH group . The remaining group `C_(3) H_(7) O` contains oxygen . The product D , having formula `C_(3) H_(5) COOH` , an unsaturated acid obtained by heating compound A `beta` - hydroxy substituted acids yield substituted acids on heating. Hence , A should be `beta` - hydroxy substitued acid i.e.
`(A) = CH_(3)- overset(OH)overset(|)(C)H - CH_(2) - COOH`
(A) on oxidation with mild oxidizing reagents will give
`CH_(3) - overset(OH)overset(|)(C)H - CH_(2) - COOH overset("Oxidation")(to) CH_(2) - overset(O)overset(||)(C) - CH_(2) - COOH`
B is keto substituted acid , hence , on further decomposition it will eliminate `CO_(2)` to give `CH_(3) - overset(O)overset(||)(C)- CH_(2) - COOH overset(-CO_(2))(to) underset((C) "Acetone")(CH_(3) COCH_(3))`