Solid-Phase Synthesis of β-Keto Sulfones

Significance

A simple method for the preparation of β-keto sulfones by polystyrene-supported benzeneselenosulfonate and tolueneselenosulfonate was developed. Thus, polystyrene-supported selenenyl bromide 1 was prepared according to the reported procedures (K. C. Nicolaou et al. Chem. Commun. 1998, 1947-1948). Resin 1 reacted with sodium toluenesulfinate or sodium benzenesulfinate in DMF to give the resin-supported areneselenosulfonate 2 with a loading of 1.33 mmol/g (S). The reaction of resin 2 with acetylenes in the presence of catalytic amounts of AIBN in benzene gave the corresponding resin 4. Treatment of resin 4 with TFA gave β-keto sulfones 5a-h (8 examples, 73-51% yield from 2).