Access to β-Alkylated γ-Functionalized Ketones via Conjugate Additions to Arylideneisoxazol-5-ones and Mo(CO)-Mediated Reductive Cascade Reactions.

1,4-Conjugate addition of ((chloromethyl)sulfonyl)benzenes to arylideneisoxazol-5-ones, followed by one-pot, N-selective trapping in the presence of electrophiles, was investigated. This strategy led to the synthesis of new, stable N-protected isoxazol-5-ones in good yields and high diastereolectivity. The study of the reactivity of obtained products in the presence of the Mo(CO)/HO system allowed the development of a cascade reaction leading to novel methyl ketones in high yields and unchanged dr bearing an uncommon chloromethinearylsulfonyl end group.