Sequential Groebke-Blackburn-Bienaymé and Pictet-Spengler Reactions for Regioselective Synthesis of Polyheterocyclics
Wan Sin Lim1, Ashutosh Nath1, Takeru Saito1
1Department of Chemistry, University of Massachusetts Boston, Boston, Massachusetts 02125, United States.
Abstract:
A two-step process involving Groebke-Blackburn-Bienaymé (GBB) and Pictet-Spengler (PS) reactions is developed for the regioselective synthesis of a unique polycyclic scaffold containing benzazepine, imidazopyridine, and dihydropyrroloazepine rings. Density functional theory calculations indicate that the C4 position on indole is kinetically favorable for the PS reaction to give benzazepine compounds as single products.
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