title: Selectivity in Garratt-Braverman cyclization: an experimental and computational study.
abstract: Bispropargyl sulfones equipped with aromatic rings of dissimilar nature were synthesized. Under basic conditions, these sulfones isomerized to the bisallenic sulfones, creating a competitive scenario between two alternate Garratt-Braverman (GB) cyclization pathways. The observed product distribution ruled out the involvement of any ionic intermediate and supported the diradical mechanism with greater involvement of the electron-rich aromatic ring via the more nucleophilic radical. DFT-based calculations supported the diradical mechanism along with the observed selectivity.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur, India.
authors.forename: Manasi
authors.initials: M
authors.lastname: Maji
authors.forename: Dibyendu
authors.initials: D
authors.lastname: Mallick
authors.forename: Sayantan
authors.initials: S
authors.lastname: Mondal
authors.forename: Anakuthil
authors.initials: A
authors.lastname: Anoop
authors.forename: Subhendu Sekhar
authors.initials: SS
authors.lastname: Bag
authors.forename: Amit
authors.initials: A
authors.lastname: Basak
authors.forename: Eluvathingal D
authors.initials: ED
authors.lastname: Jemmis
mesh_terms: D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D008956:Models, Chemical; D015394:Molecular Structure; D013450:Sulfones / Q000138:chemical synthesis* / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D013450:Sulfones