Benzene → 2-Phenylpropanal

Participants

Reaction Steps

Into a 50-ml stainless-steel autoclave were introduced 15 mg of the rhodium complex synthesized in Example 3 (containing 0.0031 mmol of rhodium), 0.71 ml (6.20 mmol) of styrene, and 0.35 ml of benzene. The contents were stirred at 60° C. for 40 hours in an atmosphere of 50-atm carbon monoxide and 50-atm hydrogen. A small portion of the reaction mixture was taken out and filtered to remove the catalyst. This reaction mixture was analyzed by 1H NMR spectrometry to determine the conversion. As a result, the conversion was found to be 97%. The proportion of the α-methylphenylacetaldehyde to dihydrocinnamaldehyde yielded (position selectivity) was 94:6. These reaction products were converted to carboxylic acids by Jones oxidation, and then analyzed by GC using a chiral column (Chrompack Cp-Cyclodex β-236M) to determine the enantiomer excess. As a result, the enantiomer excess was found to be 82% ee.

Provenance & Evidence