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

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. ¹H NMR and HRMS studies have been conducted to define the reaction pathway.