Complete the following equations:

1.	Complete the following equations:
Answer» Solution :(a) Since the final product is an aldehyde , one precursor could be the 1, 1- dichloride, these compounds are readily hydrolysed to carbonyl compounds. The use of TWO MOLECULES of a 1, 1- dichloride and copper suggests the formation of an alkene. This is an extension of the Wurtz reaction. (c)The given reagents clearly indicates that a Grignard reaction is involved.However, aryl chlorides do not form Grignard reagents in ether, THF is necessarily a solvent. On the other hand, aryl bromides(and iodides) readily react in ether solution. The use of aqueous ammonium chloride is a safety precaution to prevent the possibility of DEHYDRATION of the alcohol(which might occur if acid is used) (d) The use of iron indicates nuclear substitution. Me is o/p directing, and there is always the possibility of a steric effect at the o-position. So, we can suggest that 4-Br product will predominate. Experimental work would have to be done to find out what are the actual RESULTS. From the literature, n it appears that the 4-Br compound is formed EXCLUSIVELY.