English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We report here the coordination-mediated resolution of methyl  o -chloromandelate, which is a key intermediate for clopidogrel, in preparative scale. The reaction of CaO, optically pure (2 R , 3 R )- O , O ′-dibenzoyltartaric acid, and methyl  o -chloromandelate in ethanol solution afforded a mixed-ligands calcium(II) complex that was further purified by stirring of the crystals in hot methanol. Methyl ( R )- o -chloromandelate was obtained in good enantiomeric excess value (&gt;99.5%) and yield (71%) by treatment of the complex with acid. At the same time, (2 R , 3 R )- O , O ′-dibenzoyltartaric acid was recovered in 72% yield. In addition, methyl ( S )- o -chloromandelate was obtained in good enantiomeric excess value (&gt;99.5%) and yield (73%) by recovery from the mother liquor and resolution with the same procedure for methyl ( R )- o -chloromandelate, except that (2 S , 3 S )- O , O ′-dibenzoyltartaric acid was used as the resolving reagent.

Calcium(II)-mediated resolution of methyl o -chloromandelate with chiral O , O ′-dibenzoyltartaric acid in preparative scale