Supporting Information First Structural Example of a Metal Un-coordinated Mesoionic Imidazo[1,5-a]pyridine and Its Precursor Intermediate Copper Complex: An Insight to The Catalytic Cycle Suprakash Roy a) , Saleem Javed b) , Marilyn M. Olmstead c) , Apurba K. Patra* a a) Department of Chemistry, National Institute of Technology Durgapur, Mahatma Gandhi Avenue, Durgapur 713 209, India b) Department of Chemistry, Indian Institute of Technology, Kanpur 208 016, India c) Department of Chemistry, University of California Davis, CA 95616 (USA) Electronic Supplementary Material (ESI) for Dalton Transactions This journal is © The Royal Society of Chemistry 2011