Synthesis of Diverse Polycyclic Compounds via Catalytic Metathesis

 

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Abstract

A variety of olefin-metathesis protocols have been used to prepare spirocyclic compounds, cyclic sulfones, and constrained α-amino acid derivatives. Conceptually, a new approach to a novel cyclophane ring system has been realized via ring-closing meta­thesis (RCM). Also, tetracyclic compounds related to anthracycline antibiotics have been assembled using Claisen rearrangement and RCM as key steps. Further, a sequential use of the Diels-Alder ­reaction and ring-opening cross-metathesis delivered highly functionalized spiroindane derivatives, and trisubstituted benzene derivatives have been assembled using Grubbs’ catalyst. Finally, the enyne and cross-enyne metathesis sequences have been used to prepare several constrained α-amino acid derivatives.

1 Introduction

2 Application of Ring-Closing Metathesis To Give Spiro­cyclic Compounds

3 Application of Ring-Closing Metathesis To Give Cyclophane Derivatives

4 Application of Ring-Closing Metathesis To Give Cyclic Sulfone Derivatives

5 Application of Ring-Closing Metathesis To Give Cyclic
α-Amino Acid Derivatives and Modified Peptides

6 Application of Ring-Closing Metathesis to Benzannulation

7 Application of Enyne Metathesis to the Synthesis of Constrained α-Amino Acid and Naphthoxepin Derivatives

8 Application of Cross-Enyne Metathesis to the Synthesis of Highly Functionalized Phenylalanine Derivatives

9 Application of Ring-Opening Cross-Metathesis to Spiro­indanes

10 Synthesis of Trisubstituted Benzene Derivatives Using Grubbs’ Catalyst

11 Metathesis of a Novel Enyne System

12 Macroheterocycles via Cross-Enyne and Ring-Closing Metathesis Cascade Reactions

13 Conclusions

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Kotha, S.; Vinodkumar, R.; Lahiri, K. unpublished results.