Recent advances in the organocatalytic synthesis of chiral C3-spiro-cyclopentaneoxindoles.

Abstract

Although there have been various reviews on the asymmetric construction of C3-spirooxindoles, there is a scarcity of reviews focusing on the asymmetric organocatalytic synthesis of C3-spiro-cyclopentaneoxindole derivatives. This particular scaffold has garnered significant attention from synthetic chemists due to its relevance in medicinal chemistry. In this review, we provide an overview of recent advancements in the asymmetric organocatalytic synthesis of various C3-spiro-cyclopentaneoxindoles using organic catalysts. The work is divided into sections according to the type of catalysis, including covalent catalysis (amine catalysis and N-heterocyclic carbene catalysis) and non-covalent catalysis (chiral phosphoric acid catalysis, hydrogen bond catalysis, and phase transfer catalysis). Furthermore, we discuss existing challenges and future directions within this field. It is our belief that this review will serve as an informative resource for researchers engaged in synthesizing C3-spiro-cyclopentaneoxindoles and inspire further advancements in this area.