An unsaturated hydrocarbon 'A' adds two molecules of H_2 and on reductive ozonolysis gives butane-1,4-dial, ethanal and propanone. Give the structure of 'A' , write its IUPAC name and explain the reactions involved.

An unsaturated hydrocarbon 'A' adds two molecules of H_2 and on reduct

1.	An unsaturated hydrocarbon 'A' adds two molecules of H_2 and on reductive ozonolysis gives butane-1,4-dial, ethanal and propanone. Give the structure of 'A' , write its IUPAC name and explain the reactions involved.
Answer» Solution :(i)Since the hydrocarbon(A) adds two molecules of `H_2` , therefore, (A) is either an alkadiene or an alkyne. (ii)On reductive ozonolysis 'A', gives three fragements , one of which is a DIALDEHYDE. Therefore , the molecule has UNDERGONE cleavage at two unsaturated SITES. In other words, hydrocarbon 'A' has two double bonds, i.e., A is an alkadiene and not an alkyne. (iii) PLACE the three fragements of reductive cleavage side by side in such a way that the dialdehyde is placed in the middle while the other two products on either side of the dialdehyde. Thus, we have, Now , REMOVE the oxygen atoms, and connect the remaining three fragments by double bonds, the structure of the alkadiene (A) is Step 3.To explain reactions involved in the question .