Divergent ring-opening coupling between cyclopropanols and alkynes under cobalt catalysis
作者:Junfeng Yang、Yixiao Shen、Yang Jie Lim、Naohiko Yoshikai
DOI:10.1039/c8sc02074d
日期:——
promote ring-opening coupling reactions between cyclopropanols and unactivated internal alkynes, affording either β-alkenyl ketones or multisubstituted cyclopentenol derivatives in good yields with good to excellent regioselectivities. The chemoselectivity between these β-alkenylation and [3 + 2] annulation reactions, which likely share a cobalt homoenolate as a key catalytic intermediate, is exquisitely
A Controllable Synthesis of Homoallyl Ketones and Multiply Substituted Cyclopentadienes by Direct Insertion of Aroyl Cyanides to Zirconacyclopentenes
作者:Shaolin Zhou、Bin Yan、Yuanhong Liu
DOI:10.1021/jo050152i
日期:2005.5.1
reaction of aroyl cyanides with zirconacyclopentenes was achieved cleanly under controlled reaction conditions. This methodology provided an extremely efficient, one-pot, and high-yield route for the synthesis of homoallyl ketones when the reaction was carried out at −50 °C. Trapping of the zirconium intermediate by a variety of electrophiles afforded functionalized homoallyl ketones. Remarkably, the