Diversity-Oriented Approach to Novel Spirocyclics via Enyne Metathesis, Diels–Alder Reaction, and a [2+2+2] Cycloaddition as Key Steps

This paper is dedicated to the memory of Professor A. Srikrishna, Department of Organic Chemistry, Indian Institute of Science, Bangalore, India.

Abstract

A simple protocol for the synthesis of indane-based spirocyclics has been developed via enyne metathesis, Diels–Alder reaction, and a [2+2+2] cycloaddition as key steps starting from indane-1,3-dione. The key diene building block was assembled by enyne metathesis. In this sequence, rongalite is used as a green reagent to prepare the sultine intermediate, which is a useful precursor to generate the transient diene.

Keywords

spirocyclic compounds - [2+2+2]-cycloaddition reaction - rongalite - enyne metathesis - Diels–Alder reaction

• References and Notes

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