Reverse of Regioselectivity in Intramolecular Nucleophilic Substitution of π-Allyl Palladium Species. Highly Selective Formation of Vinylic Cyclopropanes via the Pd(0)-Catalyzed Coupling−Cyclization Reaction of Organic Iodides with 2-(2‘,3‘-Dienyl)malonates
作者:Shengming Ma、Shimin Zhao
DOI:10.1021/ol006165u
日期:2000.8.1
Vinylic cyclopropanes were formed highly selectively via the Pd(PPh(3))(4)-catalyzed insertion-intramolecular nucleophilic substitution reaction of aryl or 1-alkenyl iodides with 2-(2', 3'-dienyl)malonates. The regioselectivity observed here is different from what was reported by Cazes et al.
An Allene Approach to Tetrahydrofuran-Fused Bicyclo[2.2.2]oct-2-enes
作者:Shihua Song、Chunling Fu、Xin Huang、Shengming Ma
DOI:10.1002/adsc.201701407
日期:2018.3.1
An efficientaccess to tetrahydrofuran‐fused bicyclo[2.2.2]oct‐2‐enes via palladium‐catalyzedcyclization of oxygen‐tethered 2,7‐alkadiynylic carbonates with 2‐(buta‐2,3‐dienyl)malononitrile has been developed. Perfect chiral induction was observed when a substituent was introduced to the propargylic position affording the optically active polycyclic products of both enantiomers. Control experiments
Off‐Cycle Catalyst Cooperativity in Amine/Transition Metal Combined Catalysis: Bicyclo[3.2.0]heptanes as Key Species in Co‐Catalytic Enantioselective Carbocyclizations
existence of off-cycle catalyst cooperativity in amine/metal combined catalysis is disclosed. The experimental and density functional theory study of the amine/metal co-catalyzed enantioselective Michael/carbocyclization cascade reaction between allenes and α,β-unsaturated aldehydes reveals that the dual catalysts can perform off-cycle cooperativity that gives access to stable bicyclo[3.2.0]heptane