Solid-phase synthesis of novel isoxazolocyclobutanones and isoxazolinocyclobutenones

[GRAPHICS] The preparation of novel isoxazolocyclobutanone and isoxazolinocyclobutenone derivatives via a traceless solid-phase sulfone linker strategy is described. Key steps in the solid-phase protocol reported here include (1) sulfinate --> sulfone alkylation, (11) four-member ring formation by sulfone dianion alkylation, (iii) heterocycle formation by nitrile oxide 1,3-dipolar cycloaddition, and (iv) traceless product release by cyclobutanol --> cyclobutanone oxidation with concomitant linker cleavage by sulfinate elimination.