Dehydrobenzoannulenes have accrued great interest due to their potential uses such as hosts for binding guest molecules and precursors to fullerenes and other carbon‐rich materials, as well as their unique properties such as conductivity or superconductivity and nonlinear optical effects. These systems have seen numerous synthetic strategies employed in their construction over the past 50 years. As alkyne chemistry has developed more recently, annulene networks with greater complexity have been possible and the field has seen a vast resurgence. This article gives an account of synthetic methods developed for the preparation of annulenic systems and describes some of the interesting observed properties. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

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As part of an investigation into new synthetic routes to poly(peri-naphthalene), the synthesis and cycloaromatization of tetraethynylbiphenyls is described. The temperature-dependent cyclization of biphenyls containing unsubstituted alkynes provides the desired perylene in good yield.

The substituents at the peri positions of dehydro[14]annulenes 1 have a dramatic effect on the stability of these macrocycles, and lead to derivatives that are stable even at elevated temperatures (up to 190°C).

The cover picture shows the influence of high pressure on the Heck cross-coupling reaction. As reflected by its generally accepted mechanism, this palladium-catalyzed reaction proceeds in a number of distinctly different steps, some of which ought to be retarded by high pressure. Yet, the overall effect leads to a significant acceleration, and the reaction has a negative volume of activation. The kinetic parameters were determined by monitoring the reaction in a massive metal cylinder Ϫ as seen in the background Ϫ by on-line FT-IR spectroscopy. Details are discussed in the article by A. de Meijere et al. on p. 2375 ff.