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An Ab Initio Study of Substituent Effects on the Electrocyclization of Silyloxyazadienes

✍ Scribed by Alessandro Bongini; Zhining Xia; Mauro Panunzio

Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
127 KB
Volume
2007
Category
Article
ISSN
1434-193X

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✦ Synopsis

Abstract

The electrocyclization of 4‐substituted 3‐silyloxy‐2‐azadienes to β‐lactams was studied at the MP2/6‐31G* level of theory and the effect of the substituents on the reactivity of the azadiene and on the stereochemistry of the cyclic products was evaluated. It was shown that the electrocyclization is favoured when the substituent in 4‐position is in the (Z) configuration and discloses an electron‐donor effect. The cyclization reactions generally lead to trans β‐lactams, but with a basic substituent cis β‐lactams are obtained as well.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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