Catalytic arylative cyclization of alkynals has been developed by the use of phosphine-free rhodium/dienecomplexes as catalysts. An asymmetric variant of this process has been successfully realized by employing a C2-symmetric chiral bicyclo[2.2.2]octadiene ligand. The rhodium/dienecatalyst system is also effective for arylative cyclization of other substrates such as alkynones and enynes, achieving multiple
Rhodium-Catalyzed Tandem Addition–Cyclization–Rearrangement of Alkynylhydrazones with Organoboronic Acids
作者:Kyoungmin Choi、Hoyoon Park、Chulbom Lee
DOI:10.1021/jacs.8b05561
日期:2018.8.22
approach allows alkyne-tethered hydrazones and organoboronic acids to undergo a cascade of addition-cyclization-rearrangement reactions to provide cycloalkene products. The process is initiated by the rhodium-catalyzed addition-cyclization and completed with the allylic diazene rearrangement. The reaction can also be rendered asymmetric by using chiral diene ligands for the rhodium catalyst, whereby