Constrained phenylalanine derivatives by enyne metathesis and Diels-Alder reaction

Abstract

A conceptually new approach for the synthesis of indane-based alpha -amino acid derivatives is reported. In this regard, the synthesis of five-membered exocyclic and five-membered inner-outer ring diene building blocks (7 and 15) containing alpha -amino acid moieties is described. Diene 15 is prepared by an enyne metathesis reaction as a key step. In this paper, a full account of our work regarding the Diels-Alder reaction of these dienes with various dienophiles, and the subsequent oxidation of the cycloadducts to give various indane-based alpha -amino acid derivatives is reported.