Syntheses and Structures of [CH2(NCnH2n)2]Mo(CO)4 (n = 4,5) Complexes with Bis(cycloamine) Ligands Easily Prepared from CH2Cl2

Dipyrrolidylmethane, CH2(pyr)2, and dipiperidylmethane, CH2(pip)2, are synthesized via the condensation of their respective secondary amine precursors and dichloromethane at room temperature in the absence of light. Their use as chelating ligands is shown by the isolation and complete characterization of [CH2(pyr)2]Mo(CO)4 and [CH2(pip)2]Mo(CO)4 complexes. X-ray analysis reveals the methylene bis(cycloamines) to possess a sharp bite angle between 61° and 63° and a strong steric impact on the surrounding carbonyl ligands as a result of their ring conformations.