Synthesis of indene-fused spiro-dibenz(ox)azepines via Rh(iii)-catalyzed cascade regioselective C–H activation/annulation

Abstract

We report an unprecedented atom-economic one-pot Cp*Rh(III)-catalyzed regioselective [3 + 2]-spiroannulation reaction between dibenz(ox)azepines and ynones, allowing the synthesis of biologically relevant novel spirocyclic dibenz(ox)azepines under operationally simple and mild...

C–H activation-initiated spiroannulation reactions and their applications in the synthesis of spirocyclic compounds

“…In 2023, Deb's group disclosed a Rh( iii )-catalysed spiroannulation of dibenz(ox)azepines with ynones leading to the formation of {7,5}-spirocyclic dibenz(ox)azepines with an attached acyl group (Scheme 5). 7 Notably, as a special class of unsymmetric CC bond sources, ynones showed exclusive regio-selectivity in participating in this formal [3 + 2] spiroannulation.…”

Sustainable Synthesis through Catalyst‐Free Photoinduced Cascaded Bond Formation

“…Biologically active azepine derivatives were previously synthesized using transition-metal catalysts or under UV irradiation. [21] However, Beeler and co-workers, in an earlier report, described azepine synthesis under visible-light conditions, albeit requiring stoichiometric amounts of strong bases. [22] More recently, Gore and co-workers developed a protocol, free from photocatalysts and transition metals, for synthesizing furan-fused dihydroazepine derivatives 5 c under visible-light (Scheme 5).…”

“…Biologically active azepine derivatives were previously synthesized using transition‐metal catalysts or under UV irradiation [21] . However, Beeler and co‐workers, in an earlier report, described azepine synthesis under visible‐light conditions, albeit requiring stoichiometric amounts of strong bases [22] .…”