Mo(CO)6-mediated ringopening reactions of calix[4]arene isoxazolines/isoxazoles provide a new synthetic methodology for calix[4]arenes carrying bifunctional β-hydroxy ketones or α,β-unsaturated-β-amino ketones. Mo(CO)6 is a highly selective and convenient reagent for the ringopening process of these supramolecular isoxazolines/isoxazoles.