Highly (<i>E</i>)-Selective BF<sub>3</sub>·Et<sub>2</sub>O-Promoted Allylboration of Chiral Nonracemic α-Substituted Allylboronates and Analysis of the Origin of Stereocontrol
作者:Ming Chen、William R. Roush
DOI:10.1021/ol1007444
日期:2010.6.18
delta-Methyl-substituted homoallylic alcohols 2 were prepared in 71-88% yield, E:Z>30:1 and 93% to >95% ee via BF3 center dot Et2O-promoted allylboration with alpha-Me-allylboronate 1. The origin of high (E)-selectivity is proposed.
A Catalytic Approach for Enantioselective Synthesis of Homoallylic Alcohols Bearing a <i>Z</i>-Alkenyl Chloride or Trifluoromethyl Group. A Concise and Protecting Group-Free Synthesis of Mycothiazole
作者:Ryan J. Morrison、Farid W. van der Mei、Filippo Romiti、Amir H. Hoveyda
DOI:10.1021/jacs.9b11178
日期:2020.1.8
catalytic processes and is expected to facilitate the preparation of bioactive organic molecules. More specifically, Z-chloro-substituted allylic pinacolatoboronate is first obtained through stereoretentive cross-metathesisbetween Z-crotyl-B(pin) (pin = pinacolato) and Z-dichloroethene, both of which are commercially available. The organoboron compound may be used in the central transformation of the entire