Asymmetric Cascade Michael‐Cyclopropanation‐Rearrangement to Spiro[Furo[2,3‐ d ]Pyrimidines]

Abstract An unprecedented organocatalytic enantioselective methodology has been unlocked to access oxindole‐fused spiro[furo[2,3‐ d ]pyrimidines] with high bond efficiency (two new C─C bonds and one C─O bond) and two contiguous stereocenters via Cascade Michael‐Cyclopropanation‐Rearrangement. A series of spiro[furo[2,3‐ d ]pyrimidines] has been synthesized in excellent yield (up to 90%) and stereoselectivity (dr up to 99:1, er up to 97:3) from 3‐chlorooxindoles and 5‐alkylidene barbituric acids at room temperature. 1 H NMR and HRMS studies have been conducted to define the reaction pathway.