Chemistry of tellurium containing macrocycles

The chemistry of Tellurium containing macrocycles has received great attraction and developed rapidly. Recently inorganic chemists are fascinated by ligands containing macrocycles having tellurium as soft donor and N and O as hard donor atoms. The tellurium atom is more electropositive than carbon due to its large size that resulted in polarisation of Te-C bond. So, tellurium containing macrocycles are explored due to their high reactivity and toxicity. Well-designed macrocycles containing different metals is an interesting field of chemistry as macrocycle with mixed donor atoms can bind two different metal atoms with different nature within the same cavity and thereby ion selectivity increases. Chemistry of macrocycles with tellurium as soft donor atoms also gives rise to very interesting coordination behaviour as addition of Tellurium in macrocycle adds an additional probe (Te-125 NMR help to monitor their structures in solutions). The chemistry of hard and soft donors in macrocyclic framework makes interesting coordination chemistry and need to be explore. The discussion includes different types of tellurium macrocycles and their chemistry.