Efficient construction of diverse spiro[indoline-3,4'-pyrrolo[3,4- b]pyridines] via [3 + 3] cycloaddition of MBH carbonates of isatins with β-enamino maleimides

Org Biomol Chem. 2022 Sep 14;20(35):7099-7104. doi: 10.1039/d2ob01257j.

Abstract

An efficient method to construct unique spiro[indoline-3,4'-pyrrolo[3,4-b]pyridines] was successfully developed via a DABCO promoted formal [3 + 3] cycloaddition reaction of MBH carbonates of isatins with β-enamino maleimides in acetonitrile at room temperature. This reaction afforded multifunctionalized spiro[indoline-3,4'-pyrrolo[3,4-b]pyridines] and spiro[dipyrrolo[3,4-b:3',4'-e]pyridine-8,3'-indolines] in good yields and with lower diastereoselectivity. The relative configuration of the two diasteromers of the spiro compounds was clearly elucidated by the determination of eight single crystal structures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbonates
  • Cycloaddition Reaction
  • Indoles
  • Isatin* / chemistry
  • Maleimides / chemistry
  • Molecular Structure
  • Pyridines
  • Spiro Compounds* / chemistry

Substances

  • Carbonates
  • Indoles
  • Maleimides
  • Pyridines
  • Spiro Compounds
  • indoline
  • Isatin