Copper-Catalyzed Regioselective Fluorination of Allylic Halides
作者:Zuxiao Zhang、Fei Wang、Xin Mu、Pinhong Chen、Guosheng Liu
DOI:10.1002/anie.201301891
日期:2013.7.15
Group activity: A novel copper‐catalyzed fluorination of internal allylic bromides and chlorides has been developed by using Et3N⋅3 HF as the fluorine source. A functional group (FG) within the substrate is required to achieve the allylicfluorination, and a variety of secondary allylic fluoride compounds can be accessed in good yield with excellent regioselectivity.
Stereodivergent Dual Catalytic α‐Allylation of Protected α‐Amino‐ and α‐Hydroxyacetaldehydes
作者:Tobias Sandmeier、Simon Krautwald、Hannes F. Zipfel、Erick M. Carreira
DOI:10.1002/anie.201506933
日期:2015.11.23
Fully stereodivergentdual‐catalyticα‐allylation of protectedα‐amino‐ and α‐hydroxyacetaldehydes is achieved through iridium‐ and amine‐catalyzed substitution of racemic allylic alcohols with chiral enamines generated in situ. The operationally simple method furnishes useful aldehyde building blocks in good yields, more than 99 % ee, and with d.r. values greater than 20:1 in some cases. Additionally
Enantioselective α-Alkylation of Aldehydes by Photoredox Organocatalysis: Rapid Access to Pharmacophore Fragments from β-Cyanoaldehydes
作者:Eric R. Welin、Alexander A. Warkentin、Jay C. Conrad、David W. C. MacMillan
DOI:10.1002/anie.201503789
日期:2015.8.10
The combination of photoredox catalysis and enamine catalysis has enabled the development of an enantioselective α‐cyanoalkylation of aldehydes. This synergistic catalysis protocol allows for the coupling of two highly versatile yet orthogonal functionalities, allowing rapid diversification of the oxonitrile products to a wide array of medicinally relevant derivatives and heterocycles. This methodology