The reaction of 2-lithio-1,3,5-trimethyl-1,3,5-triazacyclohexane with YCp₂Cl leads to the formation of a donor-functionalised mono-anionic amide ligand, 1,3,5-trimethyl-2-(methylamidomethyl)-1,3,5-triazacyclohexane, bonded to the YCp₂ unit. The reaction involves a cleavage of the 1,3,5-triazacyclohexane ring and such a cleavage is also observed in the analogous reaction with (Me₃C)₂GaCl, where a MeNCH⁻ fragment is formed. No such cleavage occurs in the reaction of the related dilithiated bicyclic bis(3-methyl-1,3-diazacyclohex-1-yl)methane with YCpCl₂·3thf, which affords a mixed lithium–yttrium organyl.