A ketone A (C_(4)H_(8)O), which undergoes haloform reaction gives compound B on reduction. B on heating with sulphuric acid gives a compound C which forms nono-ozonide D.D on hydrolysis in presence of zinc dust gives only acetaldehyde E. Identify A,B,C,D and Egt write the reactions involved.

A ketone A (C_(4)H_(8)O), which undergoes haloform reaction gives comp

1.	A ketone A (C_(4)H_(8)O), which undergoes haloform reaction gives compound B on reduction. B on heating with sulphuric acid gives a compound C which forms nono-ozonide D.D on hydrolysis in presence of zinc dust gives only acetaldehyde E. Identify A,B,C,D and Egt write the reactions involved.
Answer» Solution :(i) Since ketone A `(C_(4)H_(8)O)` undergoes haloform reaction, it must CONTAIN the GROUPING, B must be 2-butanol ketone `A(C_(4)H_(8)O)` must be butanone `(CH_(3)COCH_(2)CH_(3))`. (ii) Since ketone A, i.e., butanone gives compound (B) on readuction, therefore, B must be 2-butanol `(CH_(3)CHOHCH_(2)CH_(3))`. (iii) Since B, i.e., 2-butanol on heating with `H_(2)SO_(4)` gives compound C which forms a mono-ozonide, therefore, compound C must be an alkene. (iv) Since alkene C forms a mono-ozonide D which on hydrolysis in presence of ZINC dust (i.e., reductive ozonolysis) gives only ACETALDEHYDE E, therefore, C must be a symmetrical alkene, i.e., 2-Butene. (v) All the reactions involved in the problem can now be explained as follows: