Benzaldehyde → 1-Phenyl-1-propanone

Participants

Reaction Conditions

Reaction Steps

Into a stainless steel autoclave with a glass liner was placed 1.5 g. of the 3-methyl-2-aminopyridyl aldimine of benzaldehyde, 75 ml of tetrahydrofuran and 0.2 g. of RhCl(PPh3)3. The autoclave was flushed with ethylene, to remove any air, then pressurized with ethylene to 150 psi, followed by heating to 180 degrees C. for 14 hours. Upon cooling the resulting dark red liquid was concentrated to one-fourth its original volume and stirred with moist silica gel in 20 ml of CH2Cl2 for 1 hour. Solvent was removed on the rotary evaporator and the product propiophenone was obtained by heating the silica gel at 130 degrees and 50 mm and collecting the distillate. The yield of propiophenone, as a clear oil, was 0.45 g., 45% yield based on starting aldimine and 1800% yield based on the rhodium catalyst.

Provenance & Evidence