Skeletally Diverse Synthesis of Indole-Fused Diazocine and Diazepine Frameworks by One-Pot, Two-Component Cascade Reaction

An expeditious and novel strategy
has been explored for the synthesis
of structurally diverse indole-fused diazocine and diazepine derivatives.
A substrate-based diversification approach of methyl-3-aminoindole/indoline
benzoates coupled with the Pictet–Spengler reaction and three
different reaction cascades furnished indolodiazepine and indoloquinoxalines.
The formation of indolodiazocines proceeds through an initial condensation
followed by intramolecular alkylation.