title: Aryl radical cyclizations of 1-(2'-bromobenzyl)isoquinolines with AIBN-Bu3SnH: formation of aporphines and indolo
abstract: [reaction: see text] Radical cyclization of alkoxy-substituted 1-(2'-bromobenzyl)-3,4-dihydroisoquinolines 1 with AIBN-Bu3SnH gave 6a,7-dehydroaporphines 2 preferentially. A steric repulsion between the respective alkoxy groups at the 7- and 3'-positions gave 5,6-dihydroindolo[2,1-a]isoquinolines 3 in a "disfavored" 5-endo cyclization mode. Radical cyclizations of the related substrates, such as 1-(2'-bromobenzoyl)isoquinolines or 1-(2'-bromo-alpha-hydroxybenzyl)isoquinolines, were also found to give the corresponding oxoaporphines or oxyaporphines.
authors.affiliation: Division of Molecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Japan.
authors.initials: K
authors.lastname: Orito
authors.initials: S
authors.lastname: Uchiito
authors.initials: Y
authors.lastname: Satoh
authors.initials: T
authors.lastname: Tatsuzawa
authors.initials: R
authors.lastname: Harada
authors.initials: M
authors.lastname: Tokuda