From all the experiments we observed that some groups are not tolerate experimental protocol like chloro and bromo halogen substituted at 5, 6, 7 position, they are de-halogenated and gave parent product (4Aa). N-allyl and N-propargyl substituted group are reduced to propyl group. Surprisingly N-Boc group is also deprotected in course of reaction and offers 4Aa (Figure ).