Novel Methodology Towards the Indole Core and Iron-Catalyzed Electrophilic Hydroamination of Alkenes

Indole-containing structures and their generation still draw much attention because of their ubiquity in natural products, medicinal compounds, and organic materials. Given this prevalence, synthetic methods toward these structural motifs are numerous, each with a distinct set of advantages and disadvantages. One significant challenge is the generation of 3,3-disubstituted indolines that are frequently encountered in indole cores. The discovery, optimization, and scope of a C3-quaternary indolenine synthesis, as well as, efforts to expand the methodology for the generation of higher order indole-containing polycycles, will be discussed. This novel reactivity also lead to a generalized synthesis of α,β-unsaturated N-aryl ketonitrones which has few literature examples. A modest start to realizing the success of 3-substituted non-N-protected indoles as a Michael donor will also be explored. Green chemistry continues to play an important role in creating a sustainable world. At the core of green chemistry is the reduction or elimination of the use or generation of hazardous substances. Catalysis by definition is green by reduction; however, many of the catalytic systems utilize toxic metals that can hamper or cause further concerns with allowable limits on industrial scales. Iron catalyzed reactions seek to replace these toxic metals with a benign one that is also relatively cheap. Nitrogen containing compounds are an important feed stock for the pharmaceutical and other industries. The iron catalyzed intermolecular hydroamination of alkenes with electrophilic amines will be discussed