# Efficient total synthesis of dehydro-δ-viniferin through metal–halogen exchange cyclization

## TL;DR

Scientists developed an efficient method to synthesize a bioactive compound called dehydro-δ-viniferin using a metal-halogen exchange process.

## Contribution

A scalable and efficient eight-step synthesis of dehydro-δ-viniferin with a 27% overall yield is presented.

## Key findings

- An eight-step synthesis of dehydro-δ-viniferin was achieved with an overall yield of 27%.
- Metal–halogen exchange cyclization and dehalogenation were key steps in the process.
- The method was successfully scaled up to multigram quantities for the first time.

## Abstract

Bioactive dehydro-δ-viniferin was synthesized through an efficient and practical eight-step route, achieving an overall yield of 27%. The synthesis process involves an intramolecular cyclization and dehalogenation via a metal–halogen exchange, producing 3-arylbenzofuran, with the di-iodinated α-aryloxyketone serving as the key intermediate. Long reaction times and the use of excess reagent i-PrMgCl·LiCl facilitate metal–halogen exchange cyclization and dehalogenation. This synthetic approach, scalable for the production of analogs, was successfully conducted for the first time in multigram quantities.

Metal–halogen exchange cyclization and dehalogenation with the di-iodinated α-aryloxyketone serving as the key intermediate resulted in a highly efficient total synthesis of dehydro-δ-viniferin in eight steps with an overall yield of 27%.