Unprecedented One-Pot, Domino Tertiary Alcohol Protection-Michael Type Addition of Halides to Morita-Baylis-Hillman Adduct of Isatin with RCOX/K2CO3: Diastereoselective Synthesis of Oxindole Appended β-Halo Esters

A facile method utilizing RDOX/K2CO3 as a novel reagent for conjugate addition of hydrogen halide, in addition to tertiary (3 degrees)-hydroxyl protection that leads to the synthesis of functionalized beta-halo Morita-Baylis-Hillman ester appended oxindoles, has been developed. The diastereoselective one-pot O-acylation-hydrohalogenation observed cannot otherwise be performed by treatment with hydrohalide. Deprotection of a 3 degrees-hydroxyl protecting group has also been demonstrated by treatment with hydrochloric acid.