NbCl5/Zn/PCy3-System-Catalyzed Intramolecular [2 + 2 + 2] Cycloadditions of Diynes and Alkenes To Form Bicyclic Cyclohexadienes.

Keisuke WatanabeYasushi SatohMotofumi KameiHirohisa FurukawaMaito FujiYasushi Obora

Published in: Organic letters (2017)

A NbCl5, Zn, and PCy3 catalytic system that generated low-valent Nb species is used for the synthesis of bicyclic cyclohexadienes from diynes and simple alkenes. A phosphine ligand is important for stabilizing low-valent Nb in the cycloaddition. The bicyclic cyclohexadiene skeleton is important in transition-metal-catalyzed intramolecular cycloadditions.

Keyphrases

transition metal
room temperature
heavy metals
energy transfer
crystal structure