Ligand Controlled Regiodivergent C₁ Insertion on Arynes for Construction of Phenanthridinone and Acridone Alkaloids

Abstract

A palladium-catalyzed regiodivergent C1 insertion multicomponent reaction involving aryne, CO, and 2-iodoaniline is established to construct the scaffolds of phenanthridinone and acridone alkaloids. Regioselective control is achieved under the guidance of selective ligands. The phenanthridinones are solely obtained under ligand-free condition. In comparison, application of the electron-abundant bidentate ligand dppm afforded the acridones with high efficiency. The release rate of the aryne from the precursor assists the regioselectivity of insertion as well, which was revealed through interval NMR tracking. A plausible mechanism was suggested based on the control experiments. Representative natural products and two types of natural product analogues were synthesized divergently through this tunable method.

Ligand‐ and Solvent‐Controlled Regio‐ and Chemodivergent Carbonylative Reactions

“…[26] Theb iologically active heterocycles phenanthridinone and acridone alkaloids were synthesized diver-gently depending on the ligand and the release rate of the arynes. [26] Theb iologically active heterocycles phenanthridinone and acridone alkaloids were synthesized diver-gently depending on the ligand and the release rate of the arynes.…”

“…In 2015, Jiang and co-workers developed ar egioselective carbonylation reaction of 2-iodoaniline with arynes (Scheme 11). [26] Theb iologically active heterocycles phenanthridinone and acridone alkaloids were synthesized diver-gently depending on the ligand and the release rate of the arynes. o-Iodoaniline reacted with the in situ generated arynes in the presence of CO and delivered phenanthridinones under ligand-free conditions.Incomparison, acridones were obtained when the electron-rich bidentate ligand bis(diphenylphosphino) methane (DPPM) was used as the ligand.…”

Liganden‐ und lösungsmittelkontrollierte regio‐ und chemodivergente Carbonylierungen

“…Jiang und Mitarbeiter entwickelten 2015 eine regioselektive Carbonylierung von 2‐Iodanilin mit Arinen (Schema ) . Die biologisch aktiven heterocyclischen Phenanthridinon‐ und Acridon‐Alkaloide wurden divergent abhängig von dem Liganden und der Freisetzungsgeschwindigkeit der Arine synthetisiert.…”

Palladium‐Catalyzed Ligand‐Controlled Selective Synthesis of Aldehydes and Acids from Aryl Halides and Formic Acid

“…During the last 50 years, many highly reactive carbonylation systems based on judicious choice of proper ligands have been developed . However, carbonylation procedures with different ligands to control the reaction selectivity under the same reaction conditions are still rare . In this chemistry, depending on the nucleophiles applied, different types of carbonylated compounds can be prepared with carbon monoxide as the carbonyl source.…”