title: Stereoselective synthesis of 2,3-disubstituted indoline, pyrrolidine and cyclic ether-fused 1,2-dihydroquinoline derivatives using alkyne iminium ion cyclization of vinylogous carbamates: switch of regioselectivity using an internal hydroxy group as a nucleophile.
abstract: An intramolecular, alkyne iminium ion cyclization of vinylogous carbamates derived from o-alkynyl anilines and N-protected homopropargyl amines is developed for the stereoselective construction of trans-2,3-disubstituted indolines and pyrrolidine derivatives, respectively. The regioselectivity of the alkyne iminium ion cyclization could be switched using a hydroxy group as an internal nucleophile resulting in cyclic ether-fused 1,2-dihydroquinolines. The entire process of nitrogen heterocycle formation can also be carried out in a 'one-pot' manner starting from o-iodo aniline derivatives.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India. sjgharpure@iitb.ac.in.
authors.forename: Santosh J
authors.initials: SJ
authors.lastname: Gharpure
authors.forename: V
authors.initials: V
authors.lastname: Prasath
authors.forename: Vinod
authors.initials: V
authors.lastname: Kumar
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002219:Carbamates / Q000737:chemistry*; D003500:Cyclization; D004986:Ether / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D007477:Ions; D015394:Molecular Structure; D011759:Pyrrolidines / Q000138:chemical synthesis / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry*; D013237:Stereoisomerism; D014753:Vinyl Compounds / Q000737:chemistry*
chemical_list: C403008:1,4-dihydroquinone; D000480:Alkynes; D002219:Carbamates; D007097:Imines; D007211:Indoles; D007477:Ions; D011759:Pyrrolidines; D011809:Quinones; D014753:Vinyl Compounds; D004986:Ether; C057812:indoline; C032519:pyrrolidine