title: Base-mediated hydroamination of propargylamine: a regioselective intramolecular 5-exo-dig cycloisomerization en route to imidazole-2-thione.
abstract: An intramolecular transition-metal-free base-mediated hydroamination of propargylamine with isothiocyanates has been achieved. This atom-economical, regioselective intramolecular 5-exo-dig cycloisomerization was utilized for the one-pot synthesis of diversely substituted imidazole-2-thione and spiro-cyclic imidazolidine-2-thione. The reaction goes to completion at room temperature via propargylthiourea and 65-97% isolated yields were obtained.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208016, India.
authors.forename: Alok
authors.initials: A
authors.lastname: Ranjan
authors.forename: Ragini
authors.initials: R
authors.lastname: Yerande
authors.forename: Prasad B
authors.initials: PB
authors.lastname: Wakchaure
authors.forename: Swapnil G
authors.initials: SG
authors.lastname: Yerande
authors.forename: Dattatraya H
authors.initials: DH
authors.lastname: Dethe
mesh_terms: D002384:Catalysis; D003500:Cyclization; D005031:Ethylenethiourea / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010293:Pargyline / Q000031:analogs & derivatives* / Q000737:chemistry; D011437:Propylamines / Q000737:chemistry*; D013237:Stereoisomerism; D013871:Thiones / Q000138:chemical synthesis*; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D007093:Imidazoles; D011437:Propylamines; D013871:Thiones; D028561:Transition Elements; C009054:propargylamine; D005031:Ethylenethiourea; D006046:Gold; C029899:imidazole; D010293:Pargyline