Diastereoselective Hydroformylation with Enantiopure Substrates

Stereoselective hydroformylations can benefit from the chirality in the substrate. Chirality can be part of the original substrate, but transient incorporation of 

The required substrate diene was synthesized via a multistep sequence starting from -3-methylhex-3-en-2-one. In the hydroformylation with Rh[(S,S)-BINAPHOS], the branched double bonds did not react. Moreover, the desired iso-aldehyde was preferentially formed in a diastereomeric ratio of 96 4. Since this compound was not configurationally stable during chromatography on silica. 

---