96540-30-6Relevant academic research and scientific papers
Highly asymmetric intramolecular cyclopropanation of acceptor-substituted diazoacetates by Co(II)-based metalloradical catalysis: Iterative approach for development of new-generation catalysts
Xu, Xue,Lu, Hongjian,Ruppel, Joshua V.,Cui, Xin,Lopez De Mesa, Silke,Wojtas, Lukasz,Zhang, X. Peter
, p. 15292 - 15295 (2011)
3,5-DitBu-QingPhyrin, a new D2-symmetric chiral porphyrin derived from a chiral cyclopropanecarboxamide containing two contiguous stereocenters, has been developed using an iterative approach based on Co(II)-catalyzed asymmetric cyclopropanation of alkenes. The Co(II) complex of 3,5-DitBu-QingPhyrin, [Co(P2)], has proved to be a general and effective catalyst for asymmetric intramolecular cyclopropanation of various allylic diazoacetates (especially including those with α-acceptor substituents) in high yields with excellent stereoselectivities. The [Co(P2)]-based intramolecular metalloradical cyclopropanation provides convenient access to densely functionalized 3-oxabicyclo[3.1.0]hexan-2-one derivatives bearing three contiguous quaternary and tertiary chiral centers with high enantiomeric purity.
