Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Organic Chemistry Forum for Graduate Students and Professionals => Topic started by: Parathormon on December 05, 2022, 01:03:30 PM
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Good Evening ,
I am working on some structure which contains bridged alkyl group (norbornane) - i need to attach phenyl group to one of the secondary carbons;
Molecule is quite complex and multi-step to build - its some novel PDE5 inhibitor, thats why better to use excess of phenyl-substrate;
After some consideration We are about to choose Negishi coupling or Kumada with excess of respectively phenylzinc iodide or phenylmagnesium iodide;
Convert our alkyl to iodide first and then couple with one of above methods;
The Problem is here how does theese coupling „work” in case of our alkyl halide is exo isomer which is our goal isomer - does theese methods do retention, inversion or racemize this configuration?
there is also possible to use chiral catalyst to enrich the product with desired isomer i guess but the most optimal would be to keep retention somehow because our substrate is actually chiral.