Synthesis of Aziridine‐ and Oxirane‐2‐phosphonates Spiro‐Fused with Oxindoles

Abstract

Abstract 3‐(Phosphorylmethylene)oxindoles have been prepared by a straightforward Horner–Wadsworth–Emmons reaction. They were treated with ethyl N ‐{[(4‐nitrophenyl)sulfonyl]oxy}carbamate (NsONHCO 2 Et) in the presence of CaO to afford new aziridine‐2‐phosphonates spiro‐fused with oxindole. 3‐(Phosphorylmethylene)oxindoles were also transformed into novel spiro[oxindole‐oxiranes] by reaction with H 2 O 2 /NaOH.