title: The multicomponent reaction of imidazo[1,5-a]pyridine carbenes with phthalaldehydes and dimethyl acetylenedicarboxylate: a facile construction of benzo[d]furo[3,2-b]azepines.
abstract: A study on the multicomponent reaction comprising both N-heterocyclic carbenes and substituted phthalaldehydes is reported. The imidazo[1,5-a]pyridine carbenes, namely imidazo[1,5-a]pyridine-3-ylidenes, reacted with phthalaldehydes and DMAD under very mild conditions to produce novel fused tricyclic benzo[d]furo[3,2-b]azepine derivatives. The resulting fused heterocyclic compounds are fluorescent and they give an emission around 500 nm with quantum yields (Φ(F)) being up to 0.81. This study provides not only a unique approach to fused azepine derivatives that are not easily accessible by other methods, but also opens a new avenue to complicated molecular skeletons. The fluorescence properties of long emission wavelength and high fluorescence quantum yields of some products predict their potential applications as optical sensors.
authors.affiliation: College of Chemistry, Beijing Normal University, Beijing 100875, China.
authors.forename: Huan-Rui
authors.initials: HR
authors.lastname: Pan
authors.forename: Xiao-Rong
authors.initials: XR
authors.lastname: Wang
authors.forename: Cai-Xia
authors.initials: CX
authors.lastname: Yan
authors.forename: Zhong-Xin
authors.initials: ZX
authors.lastname: Sun
authors.forename: Ying
authors.initials: Y
authors.lastname: Cheng