Nickel-Catalyzed Asymmetric Cross-Couplings of Racemic Propargylic Halides with Arylzinc Reagents
作者:Sean W. Smith、Gregory C. Fu
DOI:10.1021/ja805165y
日期:2008.9.24
A stereoconvergent method for the catalyticasymmetric Negishi cross-coupling of racemic secondary propargylic halides with arylzincreagents has been developed. Neither family of compounds has previously been shown to be a suitable partner in such coupling processes. From a practical point of view, it is noteworthy that the catalyst components (NiCl2.glyme and pybox ligand 1) are commercially available
Catalytic asymmetric 1,2-Addition/Lactonization tandem reactions for the syntheses of chiral 3-Substituted phthalides using organozinc reagents
作者:Huayin Huang、Yabai Wang、Hua Zong、Ling Song
DOI:10.1002/aoc.4643
日期:2019.1
Using chiral phosphoramide ligand 2d‐Zn (II) complex derived from (1R,2R)‐1,2‐diphenylethylenediamine as the catalyst, we have developed efficient catalytic asymmetric 1,2‐addition/lactonization tandem reactions of diverse organozinc reagents with varied methyl 2‐formylbenzoates for the construction of optically enriched 3‐aryl or alkyl substituted phthalides, which are significant building blocks
alpha-C-arylglycosides can be obtained through the addition of aryl zinc reagents to sugar epoxides. The required aryl zinc nudeophiles can be easily obtained from the corresponding boronic acids by B-Zn exchange and attack sugar 1,2 epoxides in a highly diastereoselective fashion to generate 1,2-cis-alpha-hexapyranosyl aryl glycosides under ligand-and base-free conditions.