Compound A(C_(5)H_(10)O) forms a phenyl hydrazon and gives a negative Tollen's reagent test and iodoform test. On reduction with Zn-Hg/HCl, comound A gives n-pentane. Write the structure of 'A'.

Compound A(C_(5)H_(10)O) forms a phenyl hydrazon and gives a negative

1.	Compound A(C_(5)H_(10)O) forms a phenyl hydrazon and gives a negative Tollen's reagent test and iodoform test. On reduction with Zn-Hg/HCl, comound A gives n-pentane. Write the structure of 'A'.
Answer» Solution :Since `A(C_(5)H_(10)O)` FORMS a PHENYL hydrozone, it is a carbonyl compound. Since it gives negative Tollen's reagent test, it is not an aldehyde but it must be a ketone. Since it doesn't give iodoform test, it doesn't have `CH_(3)overset(O)overset(\|\|)(C)-CH_(2)-CH_(3)` Pentan - 3 - one. `UNDERSET(A)underset("pentan-3-one")(CH_(3)-CH_(2)-overset(O)overset(\|\|)(C)-)CH_(2)-CH_(3)+underset("phenyl hydrazine")(H_(2)N-NH-C_(6)H_(5)overset(H^(+))rarr)` `underset("diethyl")(CH_(3)-)underset("ketone")(CH_(2))-underset("phenyl")(overset(N-NH-C_(6)H_(5))overset(\|\|)(C)-CH_(2))-underset("hydrazone")(CH_(2)-CH_(3))+H_(2)O` `underset(A)underset("diethyl")(CH_(3)-CH_(2))underset("ketone")(-overset(O)overset(\|\|)(C)-)CH_(2)-CH_(3)+4[H]overset(Zn-Hg)underset("conc.HCl")rarrunderset("n-pentane")(CH_(3)-CH_(2))-CH_(2)-CH_(2)-CH_(3)+H_(2)O`