title: Catalytic Enantioselective Synthesis of Lactams through Formal [4+2] Cycloaddition of Imines with Homophthalic Anhydride.
abstract: An amide-thiourea compound, operating through a novel ion pairing mechanism, is an efficient organocatalyst for the asymmetric reaction of homophthalic anhydride with imines. N-aryl and N-alkyl imines readily undergo formal [4+2] cycloaddition to provide lactams with high levels of enantio- and diastereoselectivity. The nature of the key chiral ion pair intermediate was elucidated by DFT calculations.
authors.affiliation: Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA.
authors.forename: Claire L
authors.initials: CL
authors.lastname: Jarvis
authors.affiliation: Department of Chemistry, Binghamton University, Binghamton, NY, 13902, USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Hirschi
authors.affiliation: Department of Chemistry, Binghamton University, Binghamton, NY, 13902, USA.
authors.forename: Mathew J
authors.initials: MJ
authors.lastname: Vetticatt
authors.affiliation: Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Seidel
keywords: anion binding; asymmetric catalysis; hydrogen bonding; ion pairing; organocatalysis