title: Preparation of 1-Substituted Tetrahydro-β-carbolines by Lithiation-Substitution.
abstract: A method to prepare 1-substituted N-Boc-tetrahydro-β-carbolines was developed by lithiation followed by electrophilic substitution. The deprotonation to give the organolithium was optimized by in situ IR spectroscopy and showed that the Boc group rotates slowly at low temperature. The chemistry was applied to the synthesis of 9-methyleleagnine (N-methyltetrahydroharman) and 11-methylharmicine.
authors.affiliation: †Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Cochrane
authors.affiliation: ‡AstraZeneca, Alderley Park, Macclesfield, Cheshire SK10 4TG, United Kingdom.
authors.forename: Lorraine A
authors.initials: LA
authors.lastname: Hassall
authors.affiliation: †Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors.forename: Iain
authors.initials: I
authors.lastname: Coldham
mesh_terms: D002243:Carbolines / Q000737:chemistry*; D006247:Harmine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D008094:Lithium / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism
chemical_list: C000605193:11-methylharmicine; C000605192:9-methyleleagnine(N-methyltetrahydroharman); D002243:Carbolines; D026121:Indole Alkaloids; D009942:Organometallic Compounds; D006247:Harmine; D008094:Lithium