Highly Regioselective Palladium‐Catalyzed Carboxylation of Allylic Alcohols with CO
<sub>2</sub>
作者:Tsuyoshi Mita、Yuki Higuchi、Yoshihiro Sato
DOI:10.1002/chem.201503359
日期:2015.11.9
stoichiometric transmetalation agent under a CO2 atmosphere (1 atm). This carboxylation proceeded in a highly regioselective manner to afford branched carboxylic acids predominantly. The β,γ‐unsaturated carboxylic acid thus obtained was successfully converted into an optically active γ‐butyrolactone, a known intermediate of (R)‐baclofen.
Asymmetric Reductive and Alkynylative Heck Bicyclization of Enynes to Access Conformationally Restricted Aza[3.1.0]bicycles
作者:Xiaolei Huang、Minh Hieu Nguyen、Maoping Pu、Luoqiang Zhang、Yonggui Robin Chi、Yun‐Dong Wu、Jianrong Steve Zhou
DOI:10.1002/anie.202000859
日期:2020.6.26
Conformationallyrestricted azabicycles are becoming increasingly important in medicinal research. Asymmetric Heck bicyclization of enynes proceeds to give medicinally useful aza[3.1.0] and aza[4.1.0] bicycles with excellent enantioselectivity. The key organopalladium species after bicyclization can be trapped by silanes and terminal alkynes.
Intermolecular Aminoallylation of Alkenes Using Allyl-Oxyphthalimide Derivatives: A Case Study in Radical Polarity Effects
作者:Samuel W. Lardy、Valerie A. Schmidt
DOI:10.1002/ejoc.201901071
日期:2019.10.31
This work describes the essential radicalpolarityeffects manifested in pursuit of a group transfer radical addition to achieve alkeneaminoallylation. Each open shell intermediate along the proposed mechanistic pathway is steered to preferentially react with only one reagent.
Traversing Steric Limitations by Cooperative Lewis Base/Palladium Catalysis: An Enantioselective Synthesis of α‐Branched Esters Using 2‐Substituted Allyl Electrophiles
作者:Kevin J. Schwarz、Colin M. Pearson、Gabriel A. Cintron‐Rosado、Peng Liu、Thomas N. Snaddon
DOI:10.1002/anie.201803277
日期:2018.6.25
Cooperative catalysis enables the direct enantioselective α‐allylation of linear prochiral esters with 2‐substituted allyl electrophiles. Critical to the successful development of the method was the recognition that metal‐centered reactivity and the source of enantiocontrol are independent. This feature is unique to simultaneous catalysis events and permits logical tuning of the supporting ligands
A Pd-catalyzed spirocyclization involving a sequential carbopalladation, intramolecular C−Hactivation, and a highly regioselective alkyne insertion to afford spirooxindoles and spirodihydrobenzofurans has been achieved. The spirocyclic products were generated in good to excellent yields with complete regiocontrol in a readily scalable procedure.