Magnetic Resonance Imaging (MRI) has become a prominent imaging technique in medicine.MRI contrast agents are used to increase the sensitivity of this technique.1,4,7,10-teraazacyclododecane (cyclen) is a key macrocycle used for the synthesis of Magnetic Resonance Imaging (MRI) contrast agents. Substituting the hydrogen atoms (attached to the nitrogen atoms in the ring) of cyclen with suitable groups produce stable ligands. These ligands on complexation with Ln3+ ions lead to the formation of useful chelates. Cyclen is widely synthesized via Richman and Atkins method.Recently, a new method...