Hydrogen-Bonding Controlled Nickel-Catalyzed Regioselective Cyclotrimerization of Terminal Alkynes
Kai Yang, Pengfei Wang, Zeying Sun, Minjie Guo, Wentao Zhao, Xiangyang Tang, Guangwei Wang
Abstract
Herein we report a hydrogen-bonding controlled nickel-catalyzed regioselective cyclotrimerization of terminal alkynes in moderate to excellent yields with high regioselectivities toward 1,3,5-trisubstituted benzenes. This method features a cheap catalyst, mild reaction conditions, and excellent functional group compatibility. The Ni–B(OH)2 complex in situ generated from NiCl2·DME and tetrahydroxydiboron might act as an active catalyst. After three consecutive cis-additions of terminal alkynes, internal migratory insertion cyclization, and β-boron elimination induced aromatization, 1,3,5-trisubstituted benzenes were selectively established.
Topics & Concepts
RegioselectivityChemistryCatalysisNickelAromatizationBoronCombinatorial chemistryFunctional groupHydrogenTerminal (telecommunication)Medicinal chemistryOrganic chemistryComputer sciencePolymerTelecommunicationsCatalytic Alkyne ReactionsCatalytic C–H Functionalization MethodsOrganoboron and organosilicon chemistry