Preparative Organic Chemistry
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ChemInform Abstract: Unusual Stereo- and Regioselectivity Observed in Cycloadditions of the N-Titanated Azomethine Ylides Derived from t-Butyl (Benzylideneamino)acetate with α,β-Unsaturated Esters.
First published: September 11, 1990
Abstract
Depending on the structure of the dipolarophile and the reaction temperature, cycloaddition of N-titanated azomethine ylides such as (III) with the α,β-unsaturated esters (IV), (VII), and (X) respectively forms exo,endo- or regioisomeric cycloadducts as outlined in the reaction scheme.
ChemInform Abstract
Depending on the structure of the dipolarophile and the reaction temperature, cycloaddition of N-titanated azomethine ylides such as (III) with the α,β-unsaturated esters (IV), (VII), and (X) respectively forms exo,endo- or regioisomeric cycloadducts as outlined in the reaction scheme. The results are to be partly explained via the different reaction mechanisms of chelated and nonchelated ylide structures.
