Dabco → 4,4-Diphenyl-2-butanone

Participants

Reaction Steps

To a solution of β-oxo-δ-phenyl-benzene pentanoic acid ethyl ester (8.0 g, 0.026 mol) in 47.5 mL xylenes (15.0 eq), 1,4-diazabicyclo[2.2.2]octane (30.28 g, 0.269 mol, 10 eq) was added and the reaction mixture was first heated to reflux for 5 hours and then stirred at room temperature for 16 hours (D. H. Miles, et al, J. Org. Chem. 39, 2647 (1974)). The reaction mixture was then acidified (pH 1) with approximately 10 mL 5% HCl. This heterogeneous mixture was then filtered through Celite, thoroughly washing the bed of Celite with ether. The organic layer was washed with water, dried (MgSO4), and concentrated in vacuo to give a crude oil. Purification by flash chromatography (silica gel, 15% EtOAc/hexane) yielded 4.0 g (0.018 mol, 70%) of the desired product.

Provenance & Evidence