title: Copper iminopyrrolidinates: a study of thermal and surface chemistry.
abstract: Several copper(I) iminopyrrolidinates have been evaluated by thermogravimetric analysis (TGA) and solution based (1)H NMR studies to determine their thermal stability and decomposition mechanisms. Iminopyrrolidinates were used as a ligand for copper(I) to block previously identified decomposition routes of carbodiimide deinsertion and β-hydrogen abstraction. The compounds copper(I) isopropyl-iminopyrrolidinate (1) and copper(I) tert-butyl-iminopyrrolidinate (2) were synthesized for this study, and compared to the previously reported copper(I) tert-butyl-imino-2,2-dimethylpyrrolidinate (3) and the copper(I) guanidinate [Me(2)NC((i)PrN)(2)Cu](2) (4). Compounds 1 and 2 were found to be volatile yet susceptible to decomposition during TGA. At 165 °C in C(6)D(6), they had half-lives of 181.7 h and 23.7 h, respectively. The main thermolysis product of 1 and 2 was their respective protonated iminopyrrolidine ligand. β-Hydrogen abstraction was proposed for the mechanism of thermal decomposition. Since compound 3 showed no thermolysis at 165 °C, it was further studied by chemisorption on high surface area silica. It was found to eliminate an isobutene upon chemisoption at 275 °C. Annealing the sample at 350 °C showed further evidence of the decomposition of the surface species, likely eliminating ethene, and producing a surface bound methylene diamine.
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Canada.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Coyle
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Pallister
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Kurek
authors.forename: Eric R
authors.initials: ER
authors.lastname: Sirianni
authors.forename: Glenn P A
authors.initials: GP
authors.lastname: Yap
authors.forename: Seán T
authors.initials: ST
authors.lastname: Barry
mesh_terms: D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011759:Pyrrolidines / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D056831:Coordination Complexes; D007097:Imines; D008024:Ligands; D011759:Pyrrolidines; C582763:copper(I)isopropyl-iminopyrrolidinate; C582764:copper(I)tert-butyl-iminopyrrolidinate; D003300:Copper