Carboxylation with CO<sub>2</sub> via Brook Rearrangement: Preparation of α-Hydroxy Acid Derivatives
作者:Tsuyoshi Mita、Yuki Higuchi、Yoshihiro Sato
DOI:10.1021/ol403099f
日期:2014.1.3
rearrangement. A variety of α-substituents including aryl, alkenyl, and alkyl groups were tolerated to afford α-hydroxyacids in moderate-to-high yields. One-pot synthesis from aldehydes using PhMe2SiLi and CO2 was also possible, providing α-hydroxyacids without the isolation of an α-hydroxy silane.
Enantioselective Construction of α‐Chiral Silanes by Nickel‐Catalyzed C(sp
<sup>3</sup>
)−C(sp
<sup>3</sup>
) Cross‐Coupling
作者:Hong Yi、Wenbin Mao、Martin Oestreich
DOI:10.1002/anie.201814340
日期:2019.3.11
and yields α‐chiral silanes with high enantiocontrol. The catalyst system does not promote the cross‐coupling of the corresponding carbon analogue, corroborating the stabilizing effect of the silyl group on the alkyl radical intermediate (α‐silicon effect). Both coupling partners can be, but do not need to be, functionalized, and hence, even α‐chiral silanes with no functionalgroup in direct proximity
Copper-Catalyzed Double C(sp<sup>3</sup>)–Si Coupling of Geminal Dibromides: Ionic-to-Radical Switch in the Reaction Mechanism
作者:Hamideh Hazrati、Martin Oestreich
DOI:10.1021/acs.orglett.8b02281
日期:2018.9.7
A method for converting geminal dibromides into 1,1-disilylated alkanes is reported. The reaction is promoted by a copper(I) catalyst generated in situ from CuBr·SMe2 as a precatalyst and 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy) as a ligand. A Si–B reagent is used as the silicon pronucleophile. It is shown that the two C(sp3)–Si bond-forming events differ in mechanism, with the first being ionic