Copper-Catalyzed Cross-Coupling of Functionalized Alkyl Halides and Tosylates with Secondary and Tertiary Alkyl Grignard Reagents
作者:Peng Ren、Lucas-Alexandre Stern、Xile Hu
DOI:10.1002/anie.201204275
日期:2012.9.3
Added value: A copper‐based method is highly efficient for the cross‐coupling of alkyl electrophiles with secondary and tertiary alkylGrignardreagents. The method is distinguished by its broad substrate scope and high functional group tolerance.
Co-Catalyzed Cross-Coupling of Alkyl Halides with Tertiary Alkyl Grignard Reagents Using a 1,3-Butadiene Additive
作者:Takanori Iwasaki、Hiroaki Takagawa、Surya P. Singh、Hitoshi Kuniyasu、Nobuaki Kambe
DOI:10.1021/ja404285b
日期:2013.7.3
cobalt-catalyzed cross-coupling of alkyl (pseudo)halides with alkylGrignardreagents in the presence of 1,3-butadiene as a ligand precursor and LiI is described. Sterically congested quaternary carbon centers could be constructed by using tertiary alkylGrignardreagents. This reaction proceeds via an ionic mechanism with inversion of stereochemistry at the reacting site of the alkylhalide and is compatible with
are well tolerated. The cross-coupling of alkyl (pseudo)halides with alkyl Grignard reagents is catalyzed efficiently by a cobalt(II) chloride–lithium iodide–1,3-diene catalytic system, which provides a new synthetic tool for constructing sp3 carbon chains. This system is particularly useful for creating quaternary carbon centers via the use of tertiary alkyl Grignard reagents. Various functional groups
Reactions of 1-halo-5-hexenes with alkyllithiums. Evidence for a pronounced halogen effect on the mechanism of the metal—halogen interchange reaction of primary alkyl halides
作者:William F Bailey、Jeffrey J Patricia、Timo T Nurmi
DOI:10.1016/s0040-4039(00)84396-8
日期:1986.1
Reaction of t-BuLi with 1-halo-5-hexenes and 1-halo-6-methyl-5-heptenes at −78°C has revealed that, whereas 1° alkyl iodides are cleanly converted to alkyllithiums in a non-radical process, the corresponding 1° alkyl bromides undergo interchange at least partially via a radical-mediated, SET pathway.