Application of Allylzinc Reagents as Nucleophiles in Matteson Homologations
作者:Oliver Andler、Uli Kazmaier
DOI:10.1021/acs.orglett.1c03164
日期:2021.11.5
nucleophiles that can be used in Matteson homologations. The linear substitution products are formed almost exclusively, and excellent E selectivities are observed in reactions of reagents with sterically demanding or aryl substituents on the double bond. The allylated boronic esters obtained can be converted into trifluoroborates or subjected to further homologations. Ozonolysis of the double bond provides
Enantioselective and Catalytic Method for α-Crotylation of Aldehydes with a Kinetic Self-Refinement of Stereochemistry
作者:Andrei V. Malkov、Mikhail A. Kabeshov、Maciej Barłog、Pavel Kočovský
DOI:10.1002/chem.200802224
日期:2009.2.2
Kinetic refinery: A practical, highly stereoselective, two‐step catalytic protocol for the α‐allylation of aldehydes, starting from crotyltrichlorosilanes, has been developed (see scheme). In each reaction step, one of the stereoisomers reacted faster than the other, which resulted in a kinetic stereochemical (E/Z) self‐refinement of the system and led to the formation of virtually enantiomerically
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.