# Advances in the Total Synthesis of Angular Triquinane-Type Natural Products

## TL;DR

This paper reviews recent progress in synthesizing complex angular triquinane natural products, focusing on methods to build their challenging core structure.

## Contribution

The paper introduces a systematic categorization of four major synthetic strategies for constructing angular triquinane frameworks.

## Key findings

- The Pauson–Khand reaction is a key method for constructing angular triquinane cores.
- Tandem cyclization processes and skeletal reorganization are effective for complex stereoselective synthesis.
- Innovative methods like ring-expansion and photochemistry offer new pathways for triquinane synthesis.

## Abstract

This review provides a comprehensive summary of advances in synthetic strategies for structurally complex angular triquinane natural products, with a particular emphasis on terpenoids and alkaloids over the past two decades. The formidable challenge inherent in these frameworks lies in the stereoselective construction of the congested, angularly fused triquinane core bearing one or more quaternary stereocenters. We systematically categorize and critically evaluate the key methodologies employed to construct this central motif, highlighting four major strategic approaches: (i) The Pauson–Khand reaction; (ii) tandem or cascade cyclization processes; (iii) skeletal reorganization strategies; and (iv) other innovative methods, including ring-expansion, radical cyclizations, and photochemical pathways.