Synthesis and Structural Diversity of Lanthanum and Neodymium Triphenylacetate Complexes with Trimethyltriazacyclohexane and Crown Ether

Abstract The reactions of lanthanum and neodymium triphenylacetates with polydentate 6- and 18-membered N- and O-heterocyclic ligands give various types of mononuclear triphenylacetate complexes containing a polydentate auxiliary ligand (neutral or cationic and anionic): [Nd(Ph 3 CCOO) 3 (Me 3 TACH)] ∙ CHCl 3 ( II ), [La(Ph 3 CCOO) 4 (Me 3 TACH)] – [NH 4 Me] + ( III ), [La(Ph 3 CCOO) 3 (18-crown-6)] ( IV ), and [Nd(Ph 3 CCOO) 2 (18-crown-6)] + [Nd(Ph 3 CCOO) 4 ] – ( V ) and binuclear complex [La 2 (Ph 3 CCOO) 3 -(Me 3 TACH)] ∙ 2C 6 H 5 CH 3 ( I ) (CIF files CCDC no. 1968815 ( I ), 1968813 ( II ), 1968814 ( III ), 1968812 ( IV ), and 1968816 ( V )). A minor change in the ionic radius, e.g., on going from La to Nd, results in a changed coordination environment. These changes can be followed using macrocyclic polydentate ligands.