Abstract
Aza-Heck cyclizations are an emerging method for the construction of chiral N-heterocyclic systems. In these processes, an activated N-O bond replaces the C-X bond (X = halide, OTf) used in conventional Heck reactions, with the associated aza-Pd(ii)-intermediate engaging pendant alkenes in a Heck-like manner. This perspective article commences with an historical overview of the area, which stems from Narasaka's seminal studies using oxime esters as the initiating motif. The scope and mechanism of associated chiral N-heterocyclic methodologies are then outlined, including cascade processes that enable diverse alkene 1,2-carboaminations. The recent emergence of new N-O donors and the realization of highly enantioselective aza-Heck cyclizations are then discussed. Collectively, these studies suggest that the aza-Heck approach can underpin a broad family of redox-neutral and enantioselective C-N bond forming processes.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5248-5260 |
| Number of pages | 13 |
| Journal | Chemical Science |
| Volume | 8 |
| Issue number | 8 |
| DOIs | |
| State | Published - 2017 |
| Externally published | Yes |
Bibliographical note
Funding Information:We thank the EPSRC (EP/J007455/1) for financial support and Ph.D. studentships (to A. F. and I. R. H). A. F. and I. R. H. thank AstraZeneca for partial support, and N. J. R. thanks the Bristol Chemical Synthesis Doctoral Training Centre, funded by the EPSRC (EP/G036764/1), for a Ph.D. studentship. N. J. R. also thanks the SCI for a postgraduate scholarship. J. F. B. is indebted to the Royal Society for a University Research Fellowship.
Publisher Copyright:
© 2017 The Royal Society of Chemistry.