# Synthesis of 5,5,6-Fused Tricyclic Lactones: Stereocontrol of Three Consecutive Stereocenters

**Authors:** Anass Ziari, Ivana Císařová, Eliška Matoušová

PMC · DOI: 10.1021/acs.orglett.5c05086 · 2026-01-12

## TL;DR

This paper describes a new method to create complex tricyclic lactones with precise stereochemistry using a series of chemical reactions.

## Contribution

The novel contribution is a diastereoselective synthesis of tricyclic γ-lactones with three consecutive stereocenters using palladium-catalyzed reactions.

## Key findings

- A palladium-catalyzed tandem Heck/Suzuki reaction was used to synthesize strained tricyclic γ-lactones.
- The method enables stereocontrolled synthesis from simple, biomass-derived starting materials.
- The approach provides access to complex molecular scaffolds relevant in synthetic and medicinal chemistry.

## Abstract

We report a new,
highly diastereoselective method for the synthesis
of strained 5,5,6-fused tricyclic γ-lactones via a palladium-catalyzed
tandem Heck/Suzuki cross-coupling reaction, followed by epoxidation
and lactone-forming epoxide opening. Using this sequence, we prepared
tricyclic γ-lactones with three consecutive stereocenters from
simple, readily available starting materials, including one derived
from enantiomerically pure biomass-based levoglucosenone. Our method
provides a stereocontrolled approach to complex scaffolds of potential
relevance in synthetic and medicinal chemistry.

## Linked entities

- **Chemicals:** palladium (PubChem CID 23938), levoglucosenone (PubChem CID 699486)

## Full-text entities

- **Chemicals:** epoxide (MESH:D004852), 5,5,6-Fused Tricyclic Lactones (-), gamma-lactones (MESH:C430364), lactone (MESH:D007783), levoglucosenone (MESH:C512757), palladium (MESH:D010165)

## Figures

7 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12836344/full.md

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Source: https://tomesphere.com/paper/PMC12836344