title: Altering the Cyclization Modes: Temperature-Dependent Intramolecular 7-Endo-Dig vs 6-Endo-Dig Electrophilic Ring Closures.
abstract: In an attempt to construct 10-acyl-5H-benzo[e]pyrrolo[1,2-a]azepines via acid-catalyzed intramolecular alkyne carbonyl metathesis, two distinctive modes of cyclization were revealed to depend on the reaction temperatures. 5H-Benzo[e]pyrrolo[1,2-a]azepine-1-carbaldehydes with a substituent at the C11 position were obtained as major products at 90 °C as a result of intramolecular 7-endo-dig cyclization, while 6-endo-dig ring closure by electrophilic addition of nitrogen of the pyrrole to a vinyl cation generated under acidic medium followed by an unprecedented domino rearrangement process was observed at 40 °C in some cases, resulting in 5-aryl-11H-benzo[d]pyrrolo[1,2-a]azepine-1-carbaldehydes along with the former products.
authors.affiliation: College of Pharmacy and Yonsei Institute of Pharmaceutical Sciences, Yonsei University 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea.
authors.forename: Maloy
authors.initials: M
authors.lastname: Nayak
authors.affiliation: Department of Chemistry, Chungbuk National University 1 Chungdae-ro, Seowon-gu, Cheongju, Chungbuk 28644, Republic of Korea.
authors.forename: Young Kee
authors.identifier: 0000-0002-2200-8922
authors.initials: YK
authors.lastname: Kang
authors.affiliation: College of Pharmacy and Yonsei Institute of Pharmaceutical Sciences, Yonsei University 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea.
authors.forename: Ikyon
authors.identifier: 0000-0002-0849-5517
authors.initials: I
authors.lastname: Kim