M. Boorum and Lawrence T. Scott Abstract

For the synthesis of tris-annulated benzene rings, the aldol trimerization of cyclic ketones has been known as a powerful tool since the 19 century. Why the reaction works so well with some ketones (e.g., indanone) but fails so miserably with others (e.g., tetralone), however, has never been adequately explained. This chapter outlines the development and scrutiny of a hypothesis that says formation of an a,/ -unsaturated (conjugated) dimer from a cyclic ketone is vital to the success of an aldol trimerization reaction for the synthesis of a tris-annulated benzene the reaction will fail with ketones that form only / ,y-unsaturated (unconjugated) dimers. This hypothesis unifies much experimental chemistry and is supported by theoretical calculations. 

Modem Arene Chemistry. Edited by Didier Astruc 

Copyright 2002 WILEY-VCH Veriag GmbH Co. KGaA, Weinheim 

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