Atropisomerism in Styrene: Synthesis, Stability, and Applications

Atropisomeric styrenes are a class of optically active cornpounds, the chirality of which results from restricted rotation of the C(vinyl)-C(aryl) single bond. In comparison with biaryl atropisomers, the less rigid skeleton of styrenes usually leads them to have lower rotational barriers. Although it has been overlooked for a long time, scientists have paid attention to this class of unique molecules in recent years and have developed many methods for the preparation of optically active atropisomeric styrenes. In this article, we review the development of the concept of atropisomeric styrenes, along with their isolation, asymmetric synthesis, and synthetic applications. 1 Introduction 2 The Concept of Styrene Atropisomerism 3 Early Research: Separation of Optically Active Styrenes 4 Synthesis of Optically Active Styrenes 5 Stability of the Chirality of Atropisomeric Styrenes 6 Outlook