An organic compound (A) `(C_(8)H_(14)O)` forms an oxime and gives a positive haloform reaction. On ozonolysis, it gives acetone and a compound (B) `(C_(5)H_(8)O_(2))` . (B) forms a dioxime and on subjecting to oxidation reaction gives an acid (C ) `(C_(4)H_(6)O_(4))`. On treatment with excess of ammonia and strong heating, (C ) gives a neutral compound (D) `(C_(4)H_(5)O_(2)N)`. (D) on distillation with zinc dust forms pyrrloe. Suggest the possible structures of (A), (B), (C ), and (D). Explain the chemical reactions involved.

Explanation

`A(C_(4)H_(8)N_(2))overset(H(3)O^(+))(to) B(C_(4)H_(9)O_(2)N)`
Since B forms zwitter ion, it has both acidic and basic groups. B surely has an `-COOH` group as it gives off `CO_(2)` with `NaHCO_(3)`.
It must have `-NH_(2)` groups also as it forms zwitter ion.
The structure of B should be:`H_(2)N-CH_(2)CH_(2)CH_(2)-COOHhArrH_(3)overset(+)(N)-underset("Zwitter ion")(CH_(2)CH_(2)CH_(2))-overset(O)overset(||)(C)-O^(-)`
`Aoverset(H_(3)O^(+))(to)B` (with one N-atoms less)
`implies` A must be cynanide `(RCN overset(H_(3)O^(+))(to)RCOO H)`
`H_(2)N-CH_(2)CH_(2)CH_(2)CN`
Hence the structure of A should be:
`Boverset(Delta)C`