Synlett 2006(4): 0515-0526  
DOI: 10.1055/s-2006-932481
ACCOUNT
© Georg Thieme Verlag Stuttgart · New York

Carbocationic Cyclopropanation Using Tin

Jun-ichi Yoshida*
Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
Fax: +81(85)3832727; e-Mail: yoshida@sbchem.kyoto-u.ac.jp;
Further Information

Publication History

Received 26 October 2005
Publication Date:
20 February 2006 (online)

Abstract

γ-Effects of group 14 elements such as silicon and tin is discussed with the emphasis on the comparison with β-effects. Based on the striking γ-effect of tin, cyclopropantion reactions of alkenes using organotin compounds have been developed. Using ­allyl group 14 element compounds as alkenes, intramolecular ­competition between β-elimination and γ-elimination of group 14 elements has been studied. Intermolecular competition has also been examined using the reaction of allyl- and homoallyl group 14 element compounds with electrophiles. As an application of the present method in organic synthesis, intramolecularization of ­cationic cyclopropanation based on in-situ transacetalization to form unique cyclopropane structures is demonstrated.

1 Introduction

2 Control of Carbocationic Reactions Using Group 14 ­Elements

2.1 β-Effect of Silicon

2.2 β-Effect and γ-Effect of Group 14 Elements

2.3 γ-Elimination of Group 14 Elements

3 Carbocationic Cyclopropantion of Alkenes Using Tin

3.1 Carbocationic Cyclopropanation of Alkenes Using Tin-Substituted Carbonates

3.2 Carbocationic Cyclopropanation of Alkenes Using Tin-Substituted Acetals

4 Intramolecular Competition between β-Effect and γ-Effect of Group 14 Elements

5 Intermolecular Competition between β-Effect and γ-Effect of Group 14 Elements

6 Intramolecularization of Carbocationic Cyclopropanation Using Tin

7 Conclusion