Rearrangement and Cyclization Reactions by Photoinduced Electron Transfer: New Approaches for the Synthesis of Polycyclic Compounds

Prashant A. Waske; Nikolay T. Tzvetkov; Jochen Mattay

doi:10.1055/s-2007-970777

ACCOUNT

Rearrangement and Cyclization Reactions by Photoinduced Electron Transfer: New Approaches for the Synthesis of Polycyclic Compounds

Prashant A. Waske, Nikolay T. Tzvetkov, Jochen Mattay*
Fakultät für Chemie, Universität Bielefeld, Postfach 100 131, 33501 Bielefeld, Germany
Fax: +49(521)1066417; e-Mail: mattay@uni-bielefeld.de;

Abstract

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Abstract

The concept of intramolecular radical ion cyclization reactions by photoinduced electron transfer (PET) is a powerful tool for constructing complex carbocyclic and heterocyclic ring systems. In this account we describe our earlier investigations in this field followed by the development of new approaches to the synthesis of polycyclic compounds. Radical ions generated by single-electron transfer (SET) from suitable neutral molecules are used as decisive intermediates in a wide range of interesting cyclization processes and reactions. Various synthetic strategies are presented involving radical anionic or radical cationic species generated by reductive and oxidative PET, respectively.

1 Introduction
2 General Concept
3 Reductive Electron Transfer: Formation of Ketyl and
γ-Keto Radicals
4 Oxidative Electron Transfer: Formation of α- and β-Keto Radicals
5 Summary

Key words

oxidative photoinduced electron transfer - reductive photoinduced electron transfer - PET - cyclopropyl silyl ethers - silyl enol ethers - tandem rearrangement-cyclization reactions - cyclopropyl ketones

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References and Notes

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